Cole Max LCR Phono Stage

Good points:
“I thought the Internal electrical assembly was very neat and standard of  soldering was good. Depending on how you view the quality of DIY HI FI branded components….(opinions seems generally favourable) then the quality of the internal components was very good. There was actually alot more, component wise, to the phono stage than I had expected. The various switches, mono/stereo, x10/x20 can be operated without any  clicks or thumps through my speakers. …. My Previous heavily modified Audio Note kit phono stage had the usual quiet tube roar at normal volume. The Ergo Cole Max is thankfully very, very quiet even at full volume position on the AVC, at the listening seat….

The Sound?
“The supplied Russian valves acquitted themselves very well. I’ve replaced them with a (matched by me) pair of Mullard NOS E180Fs and a pair of Raytheon 5670s. These are still running In so It’s too soon to offer a definitive judgement. …

“There doesn’t appear to be any problems driving the AVC/First Watt (25K ohm Input) F2 just as Simon assured me there wouldn’t be. I’m very happy with my new stage. Just as well since It was alot dearer than any of the DIY valve stages I considered. A quick listen through a friend’s very expensive system elicited the comments that The Ergo Cole Max Is up there with the best, sound wise.”
— end of quote

 

Concept and Design

Includes Silk LCR and Step-up modules

Side and front are solid cabinet-grade bamboo wood. Top plate is anodized black 3 mm aluminum.

The power supply box is outboard using the 5AR4 rectifier tube mounted in the outboard power supply box. The box is made from aluminum plate so no problems with magnetically induced vibration. All the AC voltage stays within the box. VCS filament supply provides the heater voltage. We also use our FCUPS all film capacitor universal power supply module (with one extra RC section at the end) placed in the main unit.

phono stage:
Tubes are E180F and 2C51
LCR direct coupled
Silk Step-up transformers 10x/20x
Mute and stereo/mono switches
All the best parts possible inside, teflon sockets etc, subplate isomount

power supply:
FCUPS film cap power supply
5AR4 tube rectifier
ULNFS (ultra low noise filament supply)
connected by umbilical

Specification

Gain:
42db mm
68db mc

Frequency response: +/-1dB  20Hz – 20KHz
RIAA Accuracy: +/- 0.25dB 100Hz-10KHz
S/N Ratio:  > 80dBA
THD & N: < 0.1%
Overload margin: > 26dB  1%THD

All measurements referenced to 5mV MM, 0.5mV or 0.25mV (depends on switch setting) for MC

Tubes

Input Tubes (one pair of Russian type only included):
6N3     (Chinese)
6H3П (ПEB) (Russian)
5670 (Industrial generic)
6385 (Industrial generic)
6854 (Industrial generic)
2C51 (Western Electrics)
396A (Western Electrics)

Output Tube (one pair of Russian type only included):
6J9     (Chinese)
6Ж9П (ПE) (Russian)
6688  (Industrial generic)
E180F (Valve, Siemens, Philips etc.)

For Russian tubes the preferred suffix is listed, preferred are tubes stamped with OTK or OTK in a diamond, those are Mil-Spec accepted.

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