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Opamps

Most amplifier manufacturers use opamps. LKV only uses them in its small, optional headphone module of the Verito-1. If LKV made a dedicated headphone amplifier, opamps wouldn't be used.

Bill Hutchins believes that while opamps have low THD, they inherently color sound with their many internal stages of amplification and negative feedback. Total Harmonic Distortion isn't the only measure of distortion: your ears hear other distortions.

LKV's alternative to opamps requires matching JFETs, using high-tolerance passive components and, more subtly, manual assembly; instead of machine insertion and soldering. Open a box from an LKV phono stage competitor. You'll see nice spacing, fewer components and far better profit margins! For more detail, please see Bill's blog.

Vacuum Tubes

Bill Hutchins voiced his 2-SB & Veros One phono pre-amplifiers through a modified Linn Sondek LP12 turntable, homemade pre-amplifier, a Conrad-Johnson Premier 11 tube amplifier and homemade speakers. Bill is definitely not anti-tube!

However, any coloration is a sign of distortion. A harsh sound is distortion; so is a warm sound. Bill pursues the absolute sound as sought by Harry Pearson: "the sound of actual acoustic instruments playing in a real space."

Tubes do one thing exceptionally well: they amplify linearly over a wide frequency band, but not perfectly; especially in lower frequencies. Furthermore, they inherently don't amplify low-output moving coil cartridges and most importantly: tubes are noisy!

Negative Feedback

Negative Feedback works by initially amplifying a signal then adjusting it to a desired level. The initial stage amplifies any errors or distortions present. With 99.99% of the circuits in the world, this is wonderful because it allows consistent output from low-tolerance materials and controlling speaker drivers would be almost impossible without negative feedback.

However, by carefully choosing matched parts and demanding high-tolerance components, signals can be amplified with the barest minimum of distortion.

Step-Up Transformers

Step-up transformers are a very old, obsolete technology; even the finest ones add distortion. Solid-state circuits amplify weak signals better than transformers can.

LKV's technological competitors aren't those using step-ups for low-output moving coil cartridges, but those making hybrid phono stages of semi-conductors supplying later stages of tubes tubes.

Class A vs Class AB vs Class D

Audiophiles, such as the remarkable Nelson Pass, have long extolled the virtues of Class A for phono and control pre-amplifiers, but Class A works poorly in controlling the stop and start of speaker drivers due to insufficient damping factors. Class AB has worked well in power amplifiers.

Amplifier feedback is reduced at higher frequencies. Bruno Putzeys' great achievement was reducing Class D feedback frequency variance below Class A and Class AB variances.

LKV Research uses a Bruno Putzeys' Hypex NCore in the Verito-1.

Linear vs Switch-Mode Power Supplies

The majority of audiophile products use linear supplies. LKV designed linear supplies are incorporated in all of its products; except for the Verito-1 integrated amplifier, where Bruno Putzeys' switcher for the NCore is employed.

Switch mode supplies provide benefits in terms of weight, efficiency and low cost, but for the very best sound, linear supplies are better .

Power Conditioners

LKV's products are designed to minimize any need for conditioning power because our high levels of regulation and filtering reduce the need for such devices.

At shows like Capital Fest or T.H.E. Show, we have used an Audience Adept Response aR6 conditioner to ease our minds because power varies in hotels, but this problem is rare in modern homes.

Bluntly, choose the Veros One over a 2-SB with a power conditioner!

Microphonics

LKV has deep expertise in electronic noise suppression, but not vibration control and/or vibrations caused by electronics, if any. The feet on LKV chassis are basic. Several customers have requested advanced vibration drain/absorb/isolate products.

At this time we haven't performed any legitimate evaluations. One of our demonstration room partners, Butcher Block Acoustics, sells moderate-cost products based on maple, brass, and rubber that may interest you. Obviously, turntables and speakers demand some physical vibration control approaches.