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My MP-3 interior pic

66.108.43.8

Posted on February 10, 2016 at 19:29:44
ChasLieb
Audiophile

Posts: 284
Joined: April 7, 2002



Got My MP-3 modded by Ralph. Put in his new current sources to replace the regulator tube for the phono supply. Parts installed include V-Caps on the phono stage outputs, a lundahl choke for the filament supplies and a Khozmo attenuator wired with Takman Rex carbon film resistors for the shunts and top of the line Texas Components nude resistors for the 100k series resistors. I took the precaution of cutting up some cheap earbuds and wiring the V-Caps in series to play music through them at top volumes for 500 hrs. Even that turned out to be not enough. After a few weeks of play though, the bass came out of hiding and the music is now sublime. Have cinemag blue transformers doing step up duties for my miyajima mc.

I was chasing a vestigial hum that was only slightly perceptible but enough that it was like a pressure that was relieved when switched from Phono to Aux. After changing the filament caps, adding the chokes etc, the thing that finally did away with it was a retubing of the phono section with some NOS 12AT7s I got to replace the old chinese tubes that were there. Dead quiet with just some tube hash at the highest, never listened to volumes that I probably get from the moving coil with step-ups. Fantastic bass with delicate highs. Even in loud passages you can hear what's going on in the background, nothing is lost.

Kudos to Ralph for an amazing phono pre and for the constant quest to make it ever better.

Chas.

 

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RE: and another pic, posted on February 10, 2016 at 19:34:58
ChasLieb
Audiophile

Posts: 284
Joined: April 7, 2002



nt

 

RE: and another pic, posted on February 11, 2016 at 08:23:27
Lew
Audiophile

Posts: 10911
Location: Bethesda, Maryland
Joined: December 11, 2000
Very nice! I'm using a similar arrangement for attenuation: a stereo balanced shunt built with nude Vishays and a Khozmo. This was an obvious huge sonic improvement vs the series attenuator that was originally in my MP1, vintage about 1992. And I've switched to Vcap copper/teflon caps as well.

 

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