Marsh P2000T hybrid preamp....Should I modify??


First, I'd like to say how much I've enjoyed reading and learning about high end audio on this site!!

In regards to my question, I am seriously thinking that a modification of the Marsh P2000T is in order. My system consist of a Pioneer Elite PDR-19RW CD player/recorder, Marsh P2000T preamp, Marsh A400s amp, and Magnepan 1.6's.

After reading in this forum about microphonics, I can say that this preamp has a problem in that area. Another issue is that I can only turn the volume control up to about 11:00 or the blue LED on the A400s starts blinking!! It does get relatively loud. I got this preamp as a demo from Audio Advisor for $975, so I could afford a modification. I am thinking that I would send it to Underwood HiFi for the mods. The mod talks about reducing microphonics and lowering the gain from 23dB to 14dB. Those 2 items address problems that I've mentioned earlier.

BTW, I will be replacing the Elite CD player/recorder with a Music Hall CD-25, also modified , either by Underwood or Sound Odyssey. Thanks for your time and thoughts on this matter!!
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Well, polarity is a complex issue. Some people are sensitive to it, some are not. In a well recorded material, where relative polarity of all tracks is maintained, inverted polarity at playback is heard as lack of ambiance and pace in the mid-bass.

However, most material is not recorded in such a fashion. Often different tracks have different polarity and final polarity of the master is either "in-phase" or "out-of-phase" with the original event.

Therefore, since polarity is essentially random on most recorded material, it is not really necessary to maintain it on playback.

However, for those rare records and CDs that are recorded in constant and correct polarity it is nice to have it right on playback.

So, I do hook my speakers backwards, as per Marsh's manual. Since their manual is the first manual for a tube product that never mentions the word "tube" it is remarkable that they decided to include the relatively exotic topic of polarity into it.

I wrote to Marsh, that since their manual excludes instructions on how to change the tubes entirely, they should expect customers to start returning them in about a year, complaining of lack of air and drive.
I can report good results from bypassing the main coupling caps with REL TFT 0.1uf 400v units. The sound has gain more air and presence and improved in the areas of pace and drive.

However, the soldering required is a bit tricky, as the leads from the bypass cap can't touch the ground plane of the PWB and the main caps leads are only about 1/8" above it. Can be done - just need to be careful.
That, my friend, is why I am paying a pro to do this!! I am not a DIY type of guy when it comes to electronics.

My preamp will be delivered today...I can't wait to hear it. BTW, I also bought an Onyx XCD-88 HDCD player from Underwood HiFi with a level 1+ modification. It is the same machine as a Music Hall CD-25 which I have read many good reviews on!! Both ar made by Shanling.
Well, how does the darned thing sound after the upgrade ? I am installing Gold Point attenuators shortly and plan to add at least some of the commercial mods via homemade tinkering...
It is still breaking in, but I can report very good sound so far. I am also breaking in an Onyx XCD-88 mod unit that I bought from Underwood.

I'll send you a couple pics Dimitry!!