Mcintosh c37

[BrianPrtugal]

i have read this is a good sounding preamp but when I purchased one in great condition I tried it in a friends system jc halos with audio arrow capitola and Piegan p10s the sound was dull, , small sound stage when compared to just using the audio arrow as the preamp. Any possible thoughts on why ? What could be wrong with preamp? Could it be a matching problem with the jc1 mono blocks?
Thanks for the guidance,
Brian

 

[c_dk]

The only common issue this series of McIntosh preamps has shown over the years is the variable loudness potentiometer can need a good cleaning, it can get crackly. I assume you have it rotated fully counterclockwise and all 5 EQ controls centered.

What is it dull sounding compared to? What is a audio arrow, a DAC? You will need to have it bench test for flat frequency response to know for sure what might be going on.

I have much success restoring these 25+ year old Mac preamps but without a proper bench test it becomes guesswork.

 

[BrianPrtugal]

The unit sounded dull compared to hooking up the capitola directly to the jc1 halo monoblockks without a preamp. Are there adjustments such as bias which can go out of spec on a preamp to impact clarity resolution and soundstage? Is it like an amp where there are capacitors that if bad deminish the sound tremendously?
Thankyou for your guidance.
Brian

 

[c_dk]

I do not know of a "silver bullet" that will change what you are hearing, other than to say there could be a number of things that are not right, the preamp is from 1991.

I guess that makes it 26 years old and we do know most electrolytic caps have a expected 20 year service life.

It was a transitional preamp for McIntosh, first conceived in the last years of Gordon Gow's long tenure as President of McIntosh and then completed before and then cosmetically changed under the first year of Clarion owning Mac.

I have found a similar situation with a stock C30 and a restored C35 during a A/B comparison but it was not so much a spectral difference but the expansion of soundstage width. Why you find it dull sounding I do not know and no one will know for sure until it is bench tested.

If you were a few hours away from the SW corner of the mitten state I would invite you to stop by for a bench test.......

 

[BrianPrtugal]

Thanks cdk for the invitation. What impact would old caps have on the sound?

 

[twiiii]

I installed C-37s, and the last thing I would say about them is dull. Are they sparkling, edgy. like krell and threshold? NO. There has to be something wrong somewhere. Impedance mis match, bad cables, or maybe the unit need re conditioning. The C-37 has the best performance of any of the 16" pre-amps when it is up to par. I would be suspicious of the graphic tone control section being on the fritz. It happened to my C-34V and needed a quick trip to Audio Classics to be checked out and repaired. So maybe a thorough going through by well trained techs with experience with Mcintosh is in order. When working properly a C-37 should not add or subtract anything from the sound of a system.

 

[BrianPrtugal]

Thankyou
I was using it with a jc halo pair of monoblockks and comparing it to a audio aero prestige and Piega p10 speakers. Maybe it's a mismatch or unfair comparison. My nieghbord tried a 2500 and it also lost the sparkle and soundstage so it could be just parasound and Mcintosh don't blend well. Anyone else experience this?