What is the “Darlington Labs Sound”?

It is the sound of resistively-loaded Single-Ended Class-A amplification implemented in a unique topology. Our designs combine dynamics, liquidity, transparency, natural soundstaging, and bass and treble extension that is hard to accomplish with traditional tube designs. Our clean and musical sound also lacks the usual harshness, etch, glare, and listening fatigue commonly present in transistor, differential J-FET or op-amp designs.

With our products in their system, clients report that they are able to listen longer, and at louder volumes, resulting in greater satisfaction. They notice previously obscured details, and can now follow complex instrumental threads in the middle of a dense mix.

Unlike some of our competition, our products are not ‘colored’ or ‘warmed over’. Yet, they remain eminently musical. Even on worn discs with excess surface noise or relatively poor recordings. Many listeners report: “it doesn’t sound bright at all, yet now I’m hearing much more detail that I expected.” We let a natural and musically-appropriate treble region through without editorializing or smearing.

Our electronics retrieve more information from your records than you knew was there. This is especially noticeable in an all-analog amplification system. They’re a rare blend of ‘Just Right’….and almost impossible for our competitors to achieve with conventional solid-state transistor, BJT/FET or IC-op-amp approaches.

Mid-priced vacuum-tube units usually suffer from a notable lack of dynamics and sound ‘rolled-off’ at the frequency extremes, often times combined with a upper-midrange glare. People praise their ‘plusses’, but often go back to Solid State, getting back on that upgrade wheel searching for superior overall results.

High-end tube units using feedback often still do not provide the same level of tight bass, soundstaging, dynamics, and natural upper-midrange.

Our proprietary single-ended High-Voltage J-FET technology, combined with extremely sophisticated Power Supply regulation of our own design, allow us to deliver more marvelous analog LP sound in your home than most people have yet experienced, whether you are listening to an RCA Shaded Dog or Snoop Dogg.

We know the majority of historical and competitive units’ circuitry encyclopedically (see our extensive database in the “Audio Encyclopedia” for an overview).

Our truly unique technology allows us to achieve an inherently-balanced high level of performance. Unlike most companies who try to compete using more typical tech, whether vacuum-tube or discrete transistor (solid state) or IC’s, and look to bring in products at a certain pricepoint, we don’t need to make large sacrifices in any one particular area in order to achieve gains in other areas.

Doing so leads to the glut of products that excel in certain genres of music or for only some listeners, but are not well suited to a wide variety of music. These are the products that tend to have big divisions of supporters (“I love it”, “You need to hear it!”, “Seek it out”) vs. their numerous detractors (“Nothing special”, “I sold it”, “Not for me”, or even “Terrible”). Our return rate (15-day return option from date of receipt) is unusually low.

We consider these weaknesses of other products the basic definition of “audible distortion”, whether subtractive (for example, a typical cost-effective-tube design) or additive (low and mid-priced transistor/IC designs).

Users also report how their spouse or partner is suddenly noticing that vinyl purchases (new and used alike) in the household have significantly increased. Clients have said that our sound is “enveloping and immersive” but rarely offputting…”tolerant of difficult or worn program material”…but “able to shine” on the best, most well-engineered discs.

For various reasons, our tech is not easily amenable to mass-production nor foreign cloning, and frankly we’re grateful that those characteristics are inherent in our preferred J-FET approach…and that we have developed implementations to build on strengths and minimize weakness. Still, however, we are following the “Botox” (and longtime high-end FOH analog console) prescription of trade secret rather than patented.

Our building reputation in the hands of current clients best tells our story.

"“[DLabs] puts me in the room with the musicians”.

“I realized that I don’t need a new cartridge after all.”

“Your product has such a rightness and natural immediacy. I could tell on first listen, after having searched for something like this for more than 30 years.”

Our small footprint (5 inches wide) is either an advantage, doesn’t matter to you, or is the only possible real compromise — if you would instead prefer a giant impressive-looking enclosure. (Note: the small box is extremely well-built, nicely-finished-in-an-understated-way, very solid when you hold it in your hand, and all-aluminum, rather than steel, for the best sound).

You have a 15-day return option for a refund (10% restocking fee) to decide if you, too, can benefit in quality of life from the reviews that you are reading.

I only use an Moving-Magnet (high-output) cartridge. Does the MP7B or MP8B offer better sound than the MM6B at the basic +40dB setting or it is just about more features?

The MP7B does offer superior sound to the MM6B in MM mode. This is likely one reason why the MP7B is our best seller when most people use high level cartridges (MM, MI or HOMC). The MP8B is even better (again in MM mode).

For the purpose of argument, first let us set aside the EQ trim and the LOMC features of the MP7B and MP8B.

While the MM6B is a spectacular value, and may be all that a basic system would need, the MP7B adds a more complex power supply (greater capacitance and better regulation) plus certain passive parts are improved. The result is somewhat deeper and tighter bass on the MP7B, with greater dynamics. The midrange and treble are also slightly more “see-through”.

When you step up to the MP8B, the sound improves again due to additional enhancements in parts quality, as well as the exclusive MP8B dual-mono power supply regulator. A wider and deeper soundstage is reported by clients. Some even say that the MP8B sounds more like good open-reel tape than an LP record, because it offers a sound so open, clean, organic, and involving.

A non-audiophile might say that they hear “more notes” in the music and this is even more true going up our model range.

We strive for neutrality in all of our designs; attempting to let the intent of the original performers and engineers shine through directly to you. Each have a balanced, musical sonic signature that doesn’t short-change any one type of music.

The conventional measured specifications are similar, and the specs support our claims of high headroom, low distortion and a technically well-executed design.

Is it true that your units actually tend to reduce Surface Noise?

Yes. Near-universal client feedback says that our designs particularly benefit their less-than-perfect vinyl, by reducing the audible impact and annoyance of surface noise, while bringing all of the music to the fore. 

This, we believe, is a combination of two things: (1) Most competitor units actually accentuate​ the noise, due to their feedback architecture and low-overload-margins, and (2) Our design with its high headroom and zero feedback circuitry subtly "rounds off" and reduces the impact of those otherwise-large voltage excursions above the normal playback level. 

Our design has NO very-low-frequency time constants in any direct gain stage. This is not true of most all op-amp designs, which use a large electrolytic capacitor to control DC offset OR must use an active DC servo. Our design also differs from most vacuum-tube units (and other FET units) which have either Cathode bypass capacitors, or Source bypass capacitors, respectively, or those that rely on Balanced or Differential operation in order to achieve a usefully-low level of distortion.

We know of no other company employing our dynamically-adaptive, frequency-selective instantaneous attack-and-release pre-emphasized limiter and clipper approach, via our entirely-directly-coupled first gain stage with a tailored frequency vs. saturation level. Our technology is similar to those employed for many years in analog FM broadcast processing to control peak modulation without undue audible side effects.

The surface noise peaks that aren’t ‘almost completely eliminated’ are modified in effective-frequency content, sounding “lower” in tone, and are passed through the rest of our circuitry including the very-high overload-margin output stage.

The music, and reduced-but-not-eliminated surface noise, is then passed intact to the rest of your system. Your preamplifier and amplifier are typically never overdriven with the remaining peaks because your downstream system, in practice, always includes a volume control with significant attenuation below “maximum output” and power amplifier clipping.

Our extremely “stiff” low-noise power supply (itself differentially-controlled and without VLF time constants) allows almost no disturbance within each stage, or between channels, in our preamplifiers during conditions of large transient compression, while maintaining clean amplification of the music.

The end result is that our combined approaches allow our units to handle large ticks and pops cleanly. No level shift or time-based transient distortion is present, allowing the soundstage to remain fixed tightly in place while surface noise ‘comes and goes’ in microseconds or milliseconds. This, we believe, is highly contributory to people’s perception that our designs allow the “music” to remain separate from the “surface noise”, the latter of which is no longer distracting for the combined set of reasons described above.

Why don’t we use ball-point-pen-operated switches?

Reliability! Those switches are notorious for intermittency and are hard to internally clean or repair. Relays are the only worse solution in our opinion. Our method is nearly foolproof, because as you remove them upward the pins are effectively self-cleaning.

In decades to come, you could replace the female portion if needed (we provide extra, but they should remain commercially available on eBay for the foreseeable future, as they are fairly widely used today in other electronic gear). While the uprightspins are gold-plated and inherently resistant to corrosion, as are the mating connectors, If needed, the user could clean those upright pins with a pencil eraser or a Q-Tip and 99% alcohol. The unit would need to be fully powered down for a period of minutes first.

In short, we build not only for incredible sonic performance now, we do so while intending to remain widely accessible to the serious upper-middle-class audio enthusiast. We also strive to appeal to the fiscally prudent upper-class consumer for their second, third, or other auxiliary and remotely-located system(s).

No matter the initial purchase transaction, we build for decades of trouble-free use and think innovatively now and for the long term, to deliver the best, longest-lasting, most thoroughly enjoyable experience to our clients.

We believe that this philosophy has contributed to our increasingly fervent and resilient client base, routinely expanding at an accelerated rate, since our founding in 2020, all with zero formal advertising and no paid sponsors or influencers to date.

Do you offer upgrades from older models (2023 and prior)?

Yes. Since early 2020, we’ve had a history of working with existing clients and treating them fairly, as you would expect for a company which has, as of yet, done zero formal advertising.

*Here is how Upgrade pricing works:

YOU MAIL US YOUR OLD UNIT, WE REMOVE AND DISCARD THE INTERNAL PRINTED CIRCUIT BOARD, AND REPLACE THE PCB WITH A NEW UNIT, REUSING YOUR CHASSIS, AND REAR PANEL INPUT/OUTPUT JACKS. We will strive to duplicate your existing LED configuration to the extent possible.

Therefore the update is the level of electrical and sonic performance OF the higher model but with your existing configuration. (Changes to configuration such as upgrading of jacks can be done at the same time as the PCB exchange, for additional cost).

Your units have internal separate MM (Moving Magnet) and MC (Moving Coil) stages plus an outboard power cube. How does this compare to others?

DLabs Vs. Standard Op-Amp or DIfferential Discrete J-FET MM/MC Competitors

The standard competitors’ combo (MM/MC) circuitry is generally a textbook implementation of low-cost op-amps, such that it can’t truly be “optimized” for either MM or MC. An op-amp with certain tradeoffs is selected, and there are typically two separate op-amp gain stages per channel.

In the MM mode, each gain stage runs at 30dB with passive RIAA sandwiched in-between. Gain in their MM Mode is approximately: +30dB in the input stage - 20dB passive RIAA loss +30dB gain in output stage = +40dB overall gain at 1kHz.

In “MC Mode”, each gain stage is increased by 10dB, to a total of 40dB per block (which is very high for a typical open-loop-op-amp-bandwidth of 100Hz). The result: +40dB input - 20dB passive RIAA loss + 40dB gain in output stage = +60dB overall gain at 1kHz. A low-valued resistor is placed in parallel with the 47K input load and then they stencil “MC mode” across a DIP switch pattern on the bottom. (This also explains odd- and often little-used-settings which fall in between 40dB and 60dB).

Ergo, you have developed a combo MM/MC unit which is particularly easy to advertise, cheap to build, and you can suggest that it is “ready for any scenario” (even a very unlikely one, like an average user suddenly buying a $2500 LOMC but really wanting to keep their old plain-vanilla preamp). However - and very importantly, we suggest — it results in only modest audio performance for either the MM or the MC mode.

Our unique design does NOT rely on Balanced or Differential operation in order to achieve a usefully-low level of distortion.

DLabs vs. “External Power Supply Chassis”

Sometimes a competitor will provide a “separate power supply box”. While it may appear impressive, the external box often features a relatively small power transformer inside. Without our advanced power supply regulation circuitry, the result still leads to compromised dynamics.

The real reason for some external power supply chassis is undoubtably the deadly trap awaiting the average designer beause they weren’t able to squeeze a low-noise MC input into the same box with any ‘real’ power supply circuitry. When they don’t use an external power supply chassis, you will note they often run an 18 or 24VDC DC wall wart (ours is an AC step-down transformer) - with minimal “real” rectification and filtration, thus further compromising their already-present overload and distortion issues.

We run an internal +/-20VDC supply on the SU series, with a very low audio noise floor, even though our fundamental MC gain approach is more sensitive to power supply disturbance than theirs. To be fair, it did take us five years and over one-thousand hours of R & D dedicated to the Step-Up line. Thus, each of our units is self-contained in terms of power supply, using a simple externally-mounted AC-output step-down transformer. We can therefore dedicate all of our resources to do the necessary job to an incredibly high standard.

Interestingly, even though our MM/MP and SU series use the exact same type of wall cube, the internal power supply approach (MM/MP vs SU) is completely different. This is an additional reason for our “separates” approach - there isn’t as much internal overlap as you might expect.

To put it simply: once you hear our results, you’ll appreciate and understand the dedication, passion, and ingenuity we deployed to our design approach. Then go and buy some records with the significant cash you have left over.

Jack Panel Upgrade Option

Our new MP8B includes our best jacks at no extra cost.

For the MP7B and MM6B, you can purchase upgraded jacks: The smaller gold jacks on the right in the photo (below) are the ‘stock’ units. These gold-plated jacks are reliable and represent a big step up over the plastic and tin-pressed jacks commonly found in consumer equipment.

The jacks used by most of our competitors can shear off or break with little applied force, easily develop intermittent connections, and—with so many subtle variations—are a challenge to replace. Failure of such inexpensive connectors often means the gear has prematurely reached “end of life” and is discarded.

Our ‘upgraded’ jacks (the left ones in the photo) are larger and stronger with more robust grip on the attached patch cables (i.e., interconnects). These are patterned after a high-end ‘805’-style jack, and we hand-select each one to ensure proper fit and performance. Pricing for the upgrade varies by model.

We don’t claim dramatic sound differences between the jacks, but the upgraded units do exhibit improved connection characteristics. They also provide a visually enhanced look to the rear panel.

How does the EQ Trim feature work?

Our MP7B and MP8B have significant adjustability relative to their peers, including a user-variable EQ function called LF and HF EQ trim.  Our all-analog implementation is unlike most any other known unit in existence.

These features can be used to compensate for your cartridge's frequency response, SUT characteristics, overall system response including speakers, room and/or furnishings,, tonal quality of the associated turntable, or your individual taste or ear’s/hearing frequency response.  

We see six major potential use cases:

(1) MM cartridge optimization

One potential use case of the EQ Trim is the following scenario involving popular Audio Technica MM cartridges (their VM 540, 740, 750 and 760 — the VM95 uses a different generator).

With our MP7B's very flexible resistive loading, combined with its flexible capacitive loading options, you can lower the cartridge capacitance, taming a mid-treble peak, and then regain the lost brightness electrically through judicious use of the EQ trim. The end result is a marked increase in phase linearity and a clearer, cleaner impulse response to transients.

(2) Step-Up Transformer Optimization and Compensation

You may also compensate for deficiencies in your associated Step-Up Transformer (SUT) at the frequency extremes; or flatten out your cartridge response (possibly in conjunction with a test record and instrumentation).

(3) Cartridge Frequency Response Compensation including LOMC

EQ trim can even be adjusted separately by channel! Many cartridges have small but measurable interchannel high and low-frequency frequency response anomalies, and more than a few have excessive HF response rise from cantaliever or tip resonance. These can be largely flattened to a remarkable extent.

(4) Speakers, room and/or furnishings compensation for your analog reproduction chain. Keep your analog chain all analog! With EQ Trim you may be able to bypass your digital room correction.

(5) Compensation for the tonal quality of the associated turntable and arm. Many people believe that different turntables and arms sound different, even when using the exact same cartridge. Slight EQ adjustment in the phono preamp, such as our EQ Trim, can optimize your full complete analog chain without adding any additional or unnecessary circuitry, and without subjecting your precious analog signal to unnecessary digital conversion or degradation.

(6) Compensation for human ear’s response. It is a fact of life that the human ear’s response changes over a lifetime. Particularly acute is high-frequency loss, associated with age or exposure to loud noise. Our signal path is so clean and clear, you can achieve a remarkable treble increase while maintaining an open sound and avoiding harshness. Between the LF and HF trim, you can even add a tiny bit of extra boom and sizzle, like one recent reviewer asked for, with minimal drawback. Try it and see.

Especially if you are a ‘tweaker’, then the flexibility of the MP7B or MP8B will be a powerful tool for your overall system and your satisfaction, growing and changing with your system needs in a unique high-performance manner.

Do you sell through dealers (for example, in Europe)?

No. We sell direct to the end-consumer in all parts of the world; and currently do not use resellers, distributors, nor dealers, in Europe or the USA or elsewhere. 

The reason is this: 

Distributors typically require a 20% markup in our business, and retail dealers often employ a 50% markup.  We also still need to get the products there (from us to you).   Therefore, if we were to offer it through these traditional channels, is it likely that our prices would be 20% to 70% higher.  

Our products are very reliable, and require almost no service.  However, if you do purchase from us in the USA and then have a warranty issue outside the US, we will pay for shipping both ways on a repair. This almost never happens, again due to our reliability. About 10 to 15% of our business is international. 

Do you ship internationally (to Non-US addresses?)

Yes, we ship internationally. As of 1/21/24, we’ve added international address support to the website so non-US users should now be able to check out directly on the website. We have moved to a flat-rate international shipping charge of $60 for one unit and $90 for two units ($30 base order charge plus $30 per model).

This provides predictability and allows automatic online ordering which is consistent with the functionality provided by our SAAS back-end website providers.

We also added United Parcel Service support (UPS) for domestic USA orders to be optionally chosen by clients instead of our traditional USPS service.

INTERNATIONAL CLIENTS WHO WISH TO MINIMIZE CUSTOMS FEES:

There is one additional option that is available to minimize customs cost into Canada, the UK, and the EU. Under our “Upgrades” section, choose the “Customs Mod.” We will remove the front panel and include it separately in box, together with a hex key wrench, and instructions on how to remount it. With your client-supplied Philips driver, it should be pretty simple for most users. Customs reduction is not guaranteed but works more than 90% of the time and is legal and above-board. We are converting it to a Non-Retail-Saleable item by this method. You reconvert it to a Retail item by the reassembly.

What about International AC Line Voltages?

Because our units do not employ a switching-type power supply, our remote wall cubes are necessarily different to accommodate multiple line voltages around the world.

We can provide a 230V EU-style or UK-style or AUS/NZ adapter. Please confirm with us your voltage needs and plug needs (EU or UK) via email after your purchase (referencing your order #) if your needs differ based on what would be expected from your shipping address.

Users in parts of Japan with 100V local supply should use an international converter to step their voltage up to 120VAC for use our regular 120VAC adaptor, or secure a local 100VAC->24VAC wall cube with a 5.5mm OD (Outer Diameter), 2.1mm ID (Inner Diameter) male coaxial connector which fits our unit.

Do we set up a preamp with Custom Settings for a client?

Sorry, no. As we have streamlined production, it is no longer practical for us to keep track of client individual requests for custom settings of the jumpers.

The user can adjust them without any soldering, by following the directions in the instruction manual. If a user is having difficulty, we will try to assist.

MP8B, MP7B and MM6B units are shipped out with MM mode, 47K, 100pF, +40dB, Unbalanced Out.

Why are prices different on eBay?

eBay collects United States sales tax in all states. We only collect Massachusetts state tax on our website since that is where our LLC is registered. Additionally, the MM6B and MP7B are higher on eBay to compensate for the greatly increased sales fees they charge.

The MM5A is only available on eBay. It is a simplified MM6B with no internal user adjustments and is our committment to a unit for $199.

What cartridges do you recommend?

Our units are designed to be neutral, musical and transparent so that you do not need to “match” them to a particular type of cartridge.

Users have reported excellent experience with the Audio Technica (AT) AT-95, VM-540, VM-740, VM-750, OC9 and SA LOMC series, Ortofon 2M series (Red, Blue, Bronze, Black, LVB250), Nagaoka MP-200 and MP-500, Denon (DL-110, DL-103), Lyra, Soundsmith, Grado, Hana, Stanton, Shure, Koestsu, Benz, Dynavector, Lyra, Van den Hul, Decca, Grace, and more.

How is your mono switch configured electrically?

Our mono switch places the positive inputs from the cartridge in direct parallel (this parallel junction is accomplished in series with a 1 ohm resistor intended to damp any possible parasitic effects in the input leads). No additional circuitry is added. When not in use I.e., ’normal stereo”, there are no additional circuit elements including switches are in the signal path.

It is the equivalent of wiring a stereo cartridge to mono right at the headshell.

Ours is completely silent in its sonic operation and can be switched while listening to a record, without muting your system or worrying about transient “pops” like some of our competitors.

Step-Up Transformers are completely unaffected and our mono switch works perfectly.

What about loading effects? Not to worry. The resistive input load with our channels in parallel declines to 23.5K and capacitance increases to 200pF, but now the cartridge has its’ own coils effectively “in parallel”, meaning that the source impedance is exactly halved.

Therefore, the cartridge high-end resonance point and frequency response is unaffected and no changes to loading are necessary nor desirable.

If a user is operating an active MC Head Amp ahead of our MM-5, MM-6 or MP-7, they should use any mono switch available on the MC head amp itself.

The Mono switch is physically configured as “Mono=Up”, “Stereo=Down”.

What is Darlington Labs warranty?

The warranty of parts and labor is 12 months on each unit, from date of original purchase, to the original purchaser. At our option, we will repair or replace any unit determined by us to be defective as a result of manufacturing defect. It does not cover abuse, neglect, externally applied damage (such as excessive power spikes or the use of non-approved power adaptors), and any product which has been modified by the user without the consent of Darlington Labs, or units which have been serviced by technicians not approved in advance by Darlington Labs.

Warranty, in this context, refers to a performance level originally associated with the date of manufacture and does not cover any running changes made as part of our continuous improvement plan.

Any implied warranty relating to Darlington Labs products is limited to the duration of the warranty period. Darlington Labs LLC shall also not be liable for any consequential or incidental damage resulting from the misuse of its products. Some states do not allow the exclusion of consequential or incidental damages. Our warranty gives you specific legal rights that vary from state to state.

We reserve the right to modify the design of any product without obligation to purchasers of previously manufactured products and to change the specifications of any product without notice or obligation to any person.

What is the meaning behind the “MP” prefix vs the ‘MM’?

MP stands for Multi-Purpose - truly optimized for four different scenarios. We optimize for 1) High Quality MM and MI cartridges via the main +40dB stage, 2) Low-Output Moving Coils via our unit’s own internal active LOMC step-up stage, 3) Outboard Step-Up-Transformers (SUTs), or 4) Separate external active Head Amps (like our SU series). Our MP units feature incredibly wide-ranging loading and gain options with resistive and capacitive loading to suit almost any situation, and a great number of gain settings. This combination, based on our review of competitive products is, we believe, a rarity among quality preamps.

Are these kits?

No. The units are entirely plug-and-play, fully complete with an external AC transformer (available in 120V or 230V).

Do you offer a Black Enclosure (a Black front panel, rather than the standard Silver panel?)

Yes. Since April 2023, we have offered Black front panels as well as Silver front panels. Our pricing is now the same no matter the color of front panel you wish to choose. The rest of the enclosure (Top, Bottom, and Rear) is always black.

Is it true that some high-end competitor units are not well suited to Moving Magnet (MM) cartridges?

Yes. Counterintuitively, some of the highest-end solid-state designs are not well-suited to Moving Magnet cartridges., due to excessive fixed gain and/or input capacitance. Those designers consider the Moving Coil user their intended client. Expensive MC cartridges can also be a source of lucrative profit for dealers. If the minimum gain is 46 to 50dB, it may be a MC-optimized unit masquerading as a true MM preamp.

Darlington Labs seems to take a dim view of conventional feedback. What about the classic tube preamps and some high end FET units which appear to use it successfully?

Marantz 7, McIntosh C22, EAR 834 and both Audio Research and Conrad Johnson from the ‘70s into the ‘90s, as well as FET units including the Threshold FET-Nine and FET-Ten use feedback and are well respected.

Our primary objection to high feedback designs are those using un-degenerated differential BJT transistor input stages, either made from discrete transistors or in the input stages of BJT (Bipolar) op-amps, which represent the vast majority of our competition (purely from a price, but not performance, standpoint).

The tremendous headroom in most high-end tube units lessens the impact of negative feedback. In general, we do believe that passive RIAA is better in performance-oriented tube units and that active feedback tube RIAA has been used as a cost-saving measure but can still perform well if properly implemented.

Barrie Gilbert, a top-flight engineer with more than 60 years’ experience including at Tektronix and Analog Devices, pointed out that:

“…there is significant odd harmonic distortion even at frequencies well below the unity-gain crossover; and that the phase angle is not only a function of frequency, but also of amplitude -- that is, the op amp generates a peculiar kind of amplitude-to-phase modulation, something which one should not expect of a linear system.

But, then, an op amp is by no means as pristine in this respect as the textbooks suggest, and that gm cell has very strong open-loop distortion for even quite small inputs.” (Barrie Gilbert, "Are Op-amps Really Linear?", Electronic Design magazine, June 10, 1998, available online at https://linearaudio.nl/sites/linearaudio.net/files/Are%20Op%20Amps%20Really%20Linear.pdf

I’d prefer an IEC power cord instead of a remote-mounted AC wall cube. Why don’t you just use a modern universal (120V/240V) switching supply?

We agree that wall warts aren’t necessarily the sexiest addition to a product at first glance. If you’ve already read our section at the top of the FAQ about upgrading the existing power cube, but still have more questions such as “why not a computer-style IEC power cord and a built-in power supply?” then this additional information may be useful.

Outboard wall warts are an important enabler of the value proposition on the 6, 7, and 8-series products. They allow us to utilize every inch inside of our enclosure with active circuitry and power supply rectification and regulation, without inducing significantly audible noise. Because of its high performance, our design is especially responsive to the quality of the power supply rails.

A large proportion of our design effort went into the discrete power supply regulation topology, one with truly exemplary line and load regulation, and low impedance, combined with low noise. In fact, it is specifically optimized for use with wall warts. Therefore, no external high current supply is needed to achieve excellent sound quality. This is part of our ‘Integrated Design Philosophy’ and is one reason why such substantial R & D resources were expended.

Our outboard linear AC power transformers have no active parts to fail (such as capacitors found in DC wall warts, nor the surface-mounted complexity of combo 120V/230V switchers), and they produce an orders-of-magnitude reduction in hash and noise compared to typical switching DC power supplies.

Around one-third to nearly one-half of our PC board space is dedicated solely to power conditioning using sophisticated all-discrete final stage power supply regulation. This is simply unheard-of in any other compact-form-factor product. However, it allows us to provide class-leading dynamic reproduction, freedom from strain, and natural sound-staging with a previously unheard-of price-to-performance ratio.

If you travel internationally, we can supply both a US 120V and an EU 230V wall wart, as well as physical travel adaptors, so that you can use them nearly anywhere in the world.

Tell us more about your company logo.

The pits represent a CD i.e. digital reproduction, the bottom of the circle represents a phonograph record i.e. analog reproduction (including tape), and the VU meter in the center represents professional audio applications. The 'Labs' portion indicates that we have engineering expertise in-house, rather than being a provider of products whose design is outsourced. While we introduced phono preamps first, our product roadmap contains Line Amplifiers, Headphone Amplifiers, Electronic Crossovers, products which interface to D/A converters, and more.

Are Darlington Labs units usable with digital phono preamps?

Yes! If a user needs the digital equalization and other features offered by such a preamp, we highly recommend the use of one of our products to properly increase the gain of your cartridge, and RIAA equalize the input signal, before feeding the output of our units to a digital preamp in a Line-In configuration.

Doing so will dramatically increase the overload margin of a digital preamp. If a digital preamp uses strictly digital EQ, at typical +40dB MM/+60dB MC gain, representative samples have been measured to enter gross overload at 20mV in, a level produced by most cartridges by regular program material (music) on a heavily modulated record, not to mention peaks above this level which result from the inevitable presence of surface noise.

Allowing basic RIAA correction to be done in the analog domain, ahead of Analog-to-Digital Conversion, can produce 20 to 30dB or more of increased headroom in the real world, leading to notably improved sonic results.

Why do we not incorporate Remote Control?

Remote control? It’s cool. But remote control typically means relays, and we have found them to be among the least reliable electronic components. We build for long-term projected reliability as being paramount and equal to our sonic priorities. Our engineering team’s background stems from professional and broadcast audio, where equipment failure or interruption can have very serious consequences.

Many audiophiles regularly use gear that is more than 40 to 60 years old. Most of those long-serving pieces do not contain relays of any type; if they do, it is almost certain they are not going to be still-in-service originals. A single relay failure in a piece of equipment containing many of them, will, for most practical purposes, result in the equipment being considered “end of life”.

Even if one could find the problem unit and replace it yourself (by soldering), most people would be tempted to replace ALL of them at the same time - an expensive proposition in parts and time. Much more likely is that the average person will be faced with prohibitively exorbitant repair costs. If the manufacturer used relays which are plug-in (extremely rare), the mating sockets themselves will contribute to sonic degradation and lack of reliability.

In our SU series, we use gold-plated DIP headers with computer-motherboard-type pin connectors which are adjusted by hand. They have proven very reliable, and are self-cleaning through simple use.

Can Darlington Labs product feed into a Balanced Line Input?

Yes! Darlington Labs high headroom designs mean that we don’t need to use a true balanced output stage, with its attendant limitations, in order for you to have compatibility feeding a Balanced Line Input from our unit. A user CAN connect any Darlington Labs unit directly to a balanced-input (XLR) with standard studio-style wiring practice (consult the factory for directions if needed).

Can Darlington Labs products interface with Balanced Output turntable?

Yes! Just because we use single-ended gain stages, by preference, does not limit the interface that a user can accommodate in his system. A user CAN connect a balanced-output cartridge/turntable combination to any of our units with standard studio-style wiring practice (consult the factory for directions if needed).

Do you offer Balanced XLR out on the Darlington Labs preamp?

No. XLRs are not currently a factory option.  While they could be added by an end user, the resulting grounding will then be inferior to our recommended method (see papers on Neil Muncy and the ‘Pin 1 Problem’ in a 1995 AES preprint).

Our solution involves custom interconnects that terminate in RCA (XLR pins 2 and 3) and spade lugs (XLR pin 1) at the Darlington Labs end, and male XLRs at the receiving end (your line level preamp, or A/D, or studio tape machine). Directions are in our owners manual and elsewhere on this website. 

Jumpers are moved internally on our unit to select the balanced out connection. The ring of the RCA then floats above ground at audio frequencies, providing an impedance-balanced out to both phases of the receiving side input. To our knowledge, our solution is entirely unique in the industry, rejects excess noise in special applications, and is sonically transparent, unlike the traditional actively-electronically-balanced XLR out.  

Why do we use a Single-Ended Input Stage?

Two reasons: First: for the same level of electronic circuitry, a Differential or Balanced Input is 3dB noisier. This is because the signal is shared between the two halves of the gain devices. Second: The distortion spectra of a Balanced stage is typically predominantly 3rd order (odd-order) distortion, which our research has determined to be detrimental to the ear’s perception of quality.

For a real-world example: Most cherished balanced in/out studio gear from decades past is passively balanced at the input and the output by physical transformers. Check the used price of recording consoles with electronically balanced inputs vs. transformer-balanced and related single-ended gain circuitry - the associated three-decade depreciation is often 20X to 60X. An Actively-Balanced In/Out Soundcraft console that sold for $90K in the early 1990s might fetch only $1500 today. On the other hand, Neve and other serious consoles using balancing transformers and internally single-ended circuitry have retained a much greater proportion of their original value. (Note that you don’t need to use transformers to interface our gear with balanced outside I/O).

We believe this is related to the ear’s response, based on over 80 years of research, which indicates that type of distortion is equally important to overall level. Note that Darlington Labs equipment, with proper interconnection by the end user, can both Receive a balanced-in signal, and handle it with low noise; as well as provide Output which is to be subsequently received by a following Balanced Line Input.

I still want a truly balanced internal architecture for a LOMC step-up.

Here is a more concise overview of the above.

While our units are fully compatible with a fully-balanced turntable and cartridge setup (whether XLR out or Mini-DIN), and they are also fully compatible with the ability to feed balanced line inputs, and reject a significant amount of externally induced noise while doing so, we realize the inherent disadvantages with using balanced or differential circuitry inside the unit.  Simply put, a higher noise floor by roughly 3dB, all else being equal, and a distinctly unmusical distortion residual high in odd-order output, even if at an overall low level. We can do it; we just choose not to. These problems are inherent in an electronically balanced internal design; few successful “classic” units are truly balanced inside the box.

Compare a Neve recording console with a Soundcraft console in the used market where the electronically balanced mic input version took a 100:1 hit in resale; the unbalanced-inside-Neve being far more highly valued and respected. Other vendors are vexxed with the same problems but are unlikely to tell you in as much honesty as we will. In fact, our most well-known direct competitor introduced a Balanced Phono Preamp in October 2023 and was quoted on video as saying that they did so because people “were asking for one”, not because “those clients actually needed one.”

While physical SUTs have their problems, if you are set on a "truly balanced" step-up, then we suggest that you consider having a vendor custom-wire a SUT (preferably with a floating internal shield), with XLR in and out rather than the customary RCA.

Can you make a Flat RIAA preamp version so that I can do RIAA in my computer software digitally?

Doing RIAA in the computer digitally is, in our studied option, a highly suboptimal solution, and therefore we do not offer this option. Different is not always better; you will send up with at most 10 to 12 bits of effective resolution for signals below 2kHz, and to preserve transients correctly you need a conventional analog phase response in the RIAA deemphasis, not a linear-phase IIR digital filter as some would have you believe.

Additionally, if you were to use an unequalized phono preamp, peak transients will tend to severely overload the front end of your A/D, exacerbating any residual TiM/SID. Our history before starting our commercial company was in professional audio and live recording, where we needed to deal extensively with digital conversion.

We can highly recommend our products feeling a regular A/D in the normal configuration. You should choose an A/D with an input impedance of 10K or greater for best compatibility with our Class-A output stages.

How generous are Darington Labs Overload Margins?

Ours is 30dB as specified on the MM/MP series and greater than 60dB (not a misprint) in our SU series. Competitors are often at least 10dB worse. Our greater overload margin equates to more freedom from audibly-distracting surface noise, pops, ticks, and clicks, as well as cleaner-sounding peaks and a generally more relaxed presentation.

Tell me about Power Supply Differences - DLabs and others:

Our high voltage rails (68V on the MM6B and MP7B, and 70V on the MP8B) are used directly and fully by each Pure J-FET and, separately and fully, by our supporting BJTs for more native internal single-ended headroom. Our J-FETs are individually hand-calibrated in all our MM and MP series in order to maximize their use of the rail.

Competitors employ “auto-bias” techniques in order for them to obviate the need for hand-matching or hand-calibrating the J-FETs used for primary gain (J-FET parameters vary, sample to sample and batch to batch).

A clue to our more efficient use of the power supply rail is the following example: One competitor who operates on what they advertise as a 64V rail (internally it is +45V/-19V) specifies a maximum single-output of 10V RMS, this using a combination of BJT+FET, not the DLabs method of Pure J-FETs.

Using our 68V or 70V rail, we specify a maximum of 17 to 19V RMS or between 48 to 50V peak-to-peak on our high-headroom single-ended out, demonstrating that we have more efficient use of the rails. This is part of our Inherent Linearity Topology which tends to reduce odd-order harmonic distortion (the kind not cancelled through differential operation).

Quality of the internal regulation OF those rails is also key:

We use exceedingly sophisticated Discrete Power Supply regulation in all of our units. Compare the PCB space dedicated to our power supply cleaning section with that of our competitors; and if you can, “probe” our power supply rails with an oscilloscope and compare them to the competion. You will likely find that our rails are nearly noise-free while others may have excessive AC noise and ripple, be polluted with mains rectification and bleedthrough, or present too high of impedance or an impedance which varies significantly with frequency - all of which tend to “color” the audio that passes through the associated gain stages.

Q: Regardless of which cartridge I use [MM, MI or MC], the MP8B [and MP7B] allow the adjustment of gain from 35dB to 72dB? In other words, an MM cartridge is not limited to +40dB gain?

A: This is correct. 

However, we have designed the unit differently than the majority of our competitors.  There are two gain blocks in an MP8B and an MP7B: 

A +40dB gain block which can be adjusted down to +37dB or +35dB; it is like the MM6B. 

There is also a Head Amp which can feed the +40dB gain block, and provide an additional +12dB, +26dB or +32dB. 

The loadings available are different to the user depending on which mode is selected. The MM mode completely bypasses the LOMC stage and this is why the loadings change depending on mode you have selected.

If the Head Amp is enabled ("MC" mode) then the MC loadings are in operation (60 ohms to 470 ohms, plus an available 62kOhms) with a fixed 1000pF capacitance.

If the Head Amp is not engaged ("MM" mode) then the MM loadings are in play (38kOhms to 1 Megohm) with Capacitances ranging from 0pF to 350pF. 

Because there is more circuitry in the signal path with the Head Amp inserted, the sonic quality is slightly better in the +35dB, +37dB, and +40dB modes.  Additionally, those modes preserve Absolute Polarity; switching in the Head Amp results in a reversed signal polarity, which itself can normally be compensated for in the headshell cartridge wiring. 

We suggest not using the +47dB mode for an MM (or other high-output-level cartridge) if you are attempting to avoid the limitations in system gain imposed by a passive preamp; insert an active line preamp after the Darlington Labs unit, and run it at a maximum gain of +40dB for the very best performance from your high-level-output cartridge.

If you are using an outboard SUT, please note that our +35dB, +37dB and +40dB modes (MM) are designed and optimized for use with outboard SUTs. If you still lack system gain/volume range then we suggest you add it after the MP7B or MP8B thorough the use of an active line stage (if you are currently using a passive line amp)

AXPONA 2025

Friday, April 11 thru Sunday, April 13th west of Chicago, IL:

https://axpona.com/exhibitors/?uww_exhid=23044847

Production Update: As of 4/13/25:

Pending orders: 16

Estimated New order timing: 2 to 6 weeks

Comments: Orders are expected to begin shipping again in mid-April.

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Sales Consultation:

EMAIL is the fastest and most preferred method of communication. We typically respond to email within 24 hours. See our Contact Tab on this website.

If you are having trouble reaching us through email, please leave a message at x617x459x7080x - removing the x’s. and provide your contact information. If needed, we will work with you to schedule a call at a time that is convenient to both you and our staff.

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