Mixed driver tube for Mcintosh MC275

Tzh21y --

1.) I don't think there is anything at all wrong with your hearing! I'm 68 and I KNOW my hearing isn't what it used to be (to say the LEAST!!) however my ability to LISTEN is better than ever ;--) I wish I could go over your system with you in person, because I know I could find out what is keeping balanced operation from sounding completely marvelous and far superior to single-ended.

2.) My long experience talking with McIntosh technical people (even those at the top) has been 'highly unsatisfactory' to be diplomatic about it ;--) You would have better luck talking with one of the engineers; at least they understand English, but they are harder to reach. See if you can get hold of Ron Evans, V.P. Engineering.

I have a couple of system specific comments:

1.) JPS interconnects are OK (as in: decent)
2.) Everything "Cardas" sucks! Way too much capacitance (especially for your Merlins) and terrible time-alignment. There may be a couple pieces of equipment on the planet that one could connect with Cardas cables, but nothing I'd want to own! ;--))
3.) I'd be interested in knowing what kinds of (good) tubes you own for the amp, and -- I almost forgot -- what (if any) tube changes you've made to the C220?

Neil
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I have the Cardas on the CD player. I am listening ( auditioning) to JPS superconductor 3 cables connected to the turntable. I can see how some can be critical of them. I have NOS Telefunkens in the C220, all Telefunkens in the 12ax7 position in the amp, GE 12at7's and Tung Sol 6550 in the 275.

I am going to plug the XLR's back in try that V1 thing again. If it still sounds different,

Tzh21y -- If you like the JPS product, you should stick with them, perhaps throughout your system for synergy. I just don't like (almost) any of Cardas' products because of their high capacitance (especially of their speaker cables) and the excessive time smear of their interconnects -- all due to all that "Golden Section" multistranding ;--)

Did your MC275 come with 6550 tubes? And what vintage Tung Sols are they? I ask because you might want to try a quad of KT88's which are more powerful and some say more accurate. I haven't tried 6550's in my amp, so I haven't compared the two. The best price/performance current KT88's are the SED's (yes, I've listened to them and tested them ;--) You can get a matched quad here for about $170 http://www.conusaudio.com The other tubes you are using are OK for now pretty much, except if you are using the C220 phono section, I would recommend tubing that part with 5751's -- either Sylvania or RCA triple-mica blackplates for ultra-quiet, great dynamics, and smooth top-to-bottom frequency response.

In order of bang for buck:
1. KT88 power tubes $170
2. JPS speaker cables (??)
3. Sylvania blackplate 6201's (12AT7's) $150/quad
4. JPS for the other cables (??)
5. RCA or Sylvania TMBP 5751's (12AX7's) for the phono section. $140 or $200 per pair respectively.
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I have 2 RCA tall plate 12ax7s that I am not using. Maybe I should try them in the phono section. I do not find the Cardas to be as bad as you are saying. They are decent cables. I may try the Anti Cable interconnect. I cant go wrong for $100.00. If I do noy like them, I will sell them here. Many here are tossing their expensive cables in favor of them. They have spent much more than I on their systems.

Tzh21y -- if you go to the Cardas website >> products >> speaker cables >> Golden Presence, you will see that speaker cable has a capacitance of 168 picofarads/foot. Just as a reference, the maximum suggested capacitance for electrostats is around 20 pf/ft. Which shouldn't be a big factor with your Merlins, which use Israeli Morel cones/domes anyway. However, most Cardas speaker cable is 350-450 pf/ft, and because I personally believe this is, well, not a 'good' thing (and is pretty much a uniquely "Cardas" characteristic) I always recommend to people using Cardas speaker cables that they experiment inexpensively by picking up some insulated solid copper 10AWG wire at Home Depot (poor man's Anti Cables, and just the opposite characteristics of Cardas!) and doing an A-B. You might be very surprised, and it will only cost you a couple dollars and a little time. If I were you I'd do this speaker cable experiment first, and hang on to the Cardas IC for now. If you like what the Home Depot wire does, you can get some Speltz Anti-Cable speaker cable (but mid-priced Virtual Dynamics solid core would be better ;--)

The RCA 17mm longplate, blackplate 12AX7's are one of my favorite 12AX7's They have a lot of balls, and if you use them in the V-2, V-5 spots, you don't want anything too strong in the 12AT7 spots or the sound will be in your face! Tellies and/or Mullies would be fine for the 12AT7's.

For phono stages, unless you're using a very low output MC (like .2mV), my favorite 12AX7 is either a Sylvania or RCA triple-mica blackplate 5751. Very quiet and SMOOTH sound (no rough edges like almost ALL 12AX7's ;--) and they always seem to have closely matched triodes right out of the box. Of course they'll cost between $150 and $225 a pair these days! I have some of those too ;--)