Strohm 2660 Variable-Mu Stereo Tube Compressor. Extremely Rare to find!!!

For sale this awesome and extremely rare to find:

Strohm 2660 – Stereo Tube Variable-Mu Compressor – Designed by Chris Strohm (Sweden)

For sale: Strohm 2660 Tube Audio Compressor, a true stereo Variable-Mu tube compressor, designed by Swedish engineer Chris Strohm and built with a no-compromise, high-end, audiophile philosophy in every aspect of its design, component choice and construction.

The design philosophy behind this unit was essentially to build the equivalent of two Fairchild 660-style compressors in one stereo unit — which is exactly why it is called 2660. In other words, this is conceptually “two 660-type Variable-Mu compressors” in a true dual mono / stereo-linkable configuration.

Today, this unit is practically impossible to find on the market, even more so in this condition.

This is not a clone and not a modern reinterpretation: this is a real Variable-Mu compressor, where gain reduction is performed directly inside the tubes by varying their bias (mu), exactly as in the classic and most respected topologies.

Construction & Internal Architecture:

This unit is a serious piece of high-end analog engineering:

14 tubes total in the circuit

8 transformers total:

4 large Lundahl transformers in the audio path

4 OEP interstage transformers

External power supply (for better noise performance, stability and headroom)

Genuine SIFAM VU meters

Very high quality potentiometers and switches

Fully discrete, all-analog, overbuilt design

True dual mono architecture with mirrored internal layout

Boutique-level assembly and wiring

The internal layout is extremely clean, logical and carefully engineered (see photos).

This is not a cost-optimized product. This is a unit designed purely for performance and sound quality.

Operation & Controls:

Dual mono / stereo linkable compressor, with independent controls per channel:

•Ratio (including limiter-style behavior)

•Attack

•Release (main recovery time)

•Time (second time constant / dynamic behavior of the release)

•Threshold

•Input

•Overdrive (directly drives the tube stages)

•Bypass per channel

•VU meter per channel

Having two release-related controls (Release + Time) allows extremely fine tuning of how the compressor breathes: from very smooth, long mastering-style recovery curves to more dynamic and musical behavior for buses and individual tracks.

What does a “true” Variable-Mu give you?

In this design, compression happens inside the tubes themselves, which results in:

Progressive, smooth and extremely musical compression

Excellent control of dynamics without destroying transients

Increased density, cohesion and 3D depth

No “mechanical” or aggressive compression artifacts

Perfect for:

•Mix bus

•Stems

•Vocals

•Bass

•Drum bus

•Acoustic material

•And mastering with character and class

Sound:

Big, deep, solid sound, with strong low end, rich mids and a very stable stereo image. It clearly feels like serious high-end analog hardware.

It can work:

In a very elegant and relatively transparent way

Or add weight, density and harmonic saturation by driving the tube stages with the Overdrive control

This is not an effect compressor. It is a high-class compressor for mix bus, mastering and high-end tracking.

Condition:

Excellent cosmetic and technical condition

Working perfectly

Always used in a studio environment

Internals in perfect condition (see photos)

No modifications

Included:

Strohm 2660 compressor

External power supply

Very careful packaging for safe shipping

•Important note for serious buyers

This is an extremely rare unit, built in very small boutique quantities and almost never seen on the market. Finding one today is practically impossible, especially in this condition.

Because of that, it naturally sits in three worlds at the same time:

A true mastering “holy grail” level tool

A collector-grade “unicorn” piece

And a pure boutique engineer-designed statement unit

This is not a mass-produced commercial product. It is a true piece of high-end, designer-made analog engineering