StereoTransmittedDisease Posted June 5, 2008 Share Posted June 5, 2008 Hello. I'm relatively new to tube gear and I was hoping for a little guidance before I throw away a lot of money. I recently purchased some Mac gear to power my Cornwalls. I picked up a C220 preamp which I love and also a MC275 which I'm not too crazy about. The bass from the 275 seems way too prominent and boomy. Also, to use an old audio cliché, it often seems as if there is a veil over the speakers - though this was at least partially alleviated by using balanced cables. Before this Mac gear I was using either one of several old Pioneer and Sansui receivers or my Marantz Reference PM-11S1. All of these sounded fine, but I really, REALLY like what tubes impart into the music. I'd be annoyed right now if the dealer hadn't given my 100% retail trade in on my Marantz... which I paid $2500 for. So I guess my question is should I just be happy with the tube preamp and hook it up to a good SS amp or should I try another tube amp? At this point I think I'd be happier just hooking the C220 up to the amp section of a good old HK 430 receiver... Has anyone here tried using the C220 with the VRD amps? Is there any reason that this combo shouldn't work? Anything else? I've read good things about Wright amps, but then I've also read that they have spurious noise issues. Any advice would be appreciated. Quote Link to comment Share on other sites More sharing options...
greg928gts Posted June 5, 2008 Share Posted June 5, 2008 This is just a quick response without really answering your question about your electronics, but something to think about. I think you should consider La Scalas or Khorns. Greg Quote Link to comment Share on other sites More sharing options...
StereoTransmittedDisease Posted June 5, 2008 Author Share Posted June 5, 2008 This is just a quick response without really answering your question about your electronics, but something to think about. I think you should consider La Scalas or Khorns. Greg I'd agree with you except one thing I forgot to mention is that these are in a reletively small room 12' x 14'. Though they work in this room with every other amp I've tried them with - not too boomy, not too bright. At first I actually couldn't believe that these big old speakers worked so well in a small space, but they really do. Quote Link to comment Share on other sites More sharing options...
oldtimer Posted June 6, 2008 Share Posted June 6, 2008 I'll top greg for lack of help, and ask you a question. You say it sounds like a veil over the speakers but you like the sound? Just food for thought. If you have'nt already, this thread is an informative read: http://forums.klipsch.com/forums/t/105034.aspx Quote Link to comment Share on other sites More sharing options...
colterphoto1 Posted June 6, 2008 Share Posted June 6, 2008 Heresy III - perfect size for that room, nice deep Heritage bass, clean sparkly highs, traditional Klipsch look and feel. Quote Link to comment Share on other sites More sharing options...
oldbuckster Posted June 6, 2008 Share Posted June 6, 2008 Maybe it's not the Cornwalls fault, maybe, just maybe, you aren't happy with the Mac ? Can you exchange it back, and try something else? Who ever said, Mac is for everyone ?????? Quote Link to comment Share on other sites More sharing options...
greg928gts Posted June 6, 2008 Share Posted June 6, 2008 I recently had a pair of Cornwalls with tube amps running in my living room and they sounded "tubby". I'm not Cornwall bashing, I love C's, but with these tube amps they were not at their best. C's have kind of a big fat bass anyway, and tubes tend to be softer and maybe not as quick with bass. I also recently had a pair of La Scalas in the same size room as the 'original poster' on the same tube amps and it was the best sounding system I have ever owned. A lot of other details enter into this, but my point is that La Scalas can be absolutely amazing in a small room, they have a better midrange than C's, and they match up especially well with tube amps. HIII's are a good choice too, I just like LS's better. STD - I'm guessing a room that size is not your living room. Dedicated music room? If so, no WAF issues. Greg Quote Link to comment Share on other sites More sharing options...
StereoTransmittedDisease Posted June 6, 2008 Author Share Posted June 6, 2008 I'll top greg for lack of help, and ask you a question. You say it sounds like a veil over the speakers but you like the sound? Just food for thought.If you have'nt already, this thread is an informative read: I guess I should clarify a bit. I do not like the sound of the Cornwall/MC275 combo at all, at least not in my room. Though I can see how it could work great in a larger room. I do have had limited experience with inexpensive tube preamps paired with SS amps and have listened to many tube amp/preamp combos on other speakers and liked what I've heard. I went into my dealers basically looking for a preamp, but he gave me slightly over 4K in trade in value for a Marantz amp that I bought used for $2500. So I figured what the hay, might as well try it, and if I don't like it then I'll still come out ahead. And that's where I'm at now: I tried it and I don't really like it, but I'm not at all fussed about it because I can still get more for r selling the Mac used than I paid for my Marantz. Heresy III - perfect size for that room, nice deep Heritage bass, clean sparkly highs, traditional Klipsch look and feel. I had Heresy's in the past and did not care for them too much - too tipped up in the highs and upper mid frequencies for my taste. The Cornwalls are the first Klipsch speakers that suit me as far as overall balance is concerned. Though I admit that the CWs and the Heresy's are the only Heritage Klipsch I've heard so far. Maybe it's not the Cornwalls fault, maybe, just maybe, you aren't happy with the Mac ? Can you exchange it back, and try something else? Who ever said, Mac is for everyone ?????? You hit the nail on the head - it's definitely not the CW's at fault here. It's the MC275 amp. I love the C220 preamp though. That's one of the things that I'm wondering - Does anyone else here use this pre or one like it with Cornwalls and if so what amps are you using. Do you think I'd be missing much by keeping the C220 and using a SS amp? What about the VRD amps? Anyone using Mac pre with these amps? I recently had a pair of Cornwalls with tube amps running in my living room and they sounded "tubby". I'm not Cornwall bashing, I love C's, but with these tube amps they were not at their best. C's have kind of a big fat bass anyway, and tubes tend to be softer and maybe not as quick with bass. I also recently had a pair of La Scalas in the same size room as the 'original poster' on the same tube amps and it was the best sounding system I have ever owned. A lot of other details enter into this, but my point is that La Scalas can be absolutely amazing in a small room, they have a better midrange than C's, and they match up especially well with tube amps. HIII's are a good choice too, I just like LS's better. STD - I'm guessing a room that size is not your living room. Dedicated music room? If so, no WAF issues. Greg Man, that sounds great... I almost hate to admit this, but my audio budget is just about tapped for a while; I was really hoping to find an answer that didn't cost me anymore money. The room is a spare bedroom that I can do with as I please, wench be damned! [] Quote Link to comment Share on other sites More sharing options...
Audio Flynn Posted June 6, 2008 Share Posted June 6, 2008 Was the MAC rebuilt or stock? Were the Corns networks rebuilt? This Amplifier was produced by McIntosh from May, 1961 through July 1973. The original Unity Coupled Circuit and McIntosh bifilar wound output transformer set a standard for low distortion performance back in 1947. The output transformer had two primary windings which are wound in a bifilar pattern. In this technique, both primaries are wound side by side. Each turn of primary number one is next to the same turn of primary number two. There is near complete magnetic coupling between the two wires. The magnetic coupling is reinforced by the capacitance between the two wires. In the McIntosh Unity Coupled Circuit, one of the bifilar primary windings is connected through the power supply to the plate and cathode of one of the output tubes. The other bifilar winding is connected to the other tube in the same manner. This unity coupled output virtually eliminates notch distortion. The MC275 used an advanced design of this technology by incorporating a trifilar wound primary to improve the power bandwidth. The third winding is connected to the plates of the cathode follower driver. Groups of interleaved primary and secondary windings improve coupling and bandwidth of over 100,000 cycles is achieved. Tube Complement: Voltage Amplifier - One 12AX7 (drives both amps) Phase Inverter - Two 12AU7 Drive Amplifier - Two 12BH7 Cathode Follower Drive - Two 12AT7 or 12AZ7 Output - Four KT88 or 6550 Selectable source input for Stereo, Twin-Amp or Mono operation. Ouput is rated at 75 watts continuous per channel in Stereo or Twin configuration. 150 watts continuous mono. Harmonic Distortion is less than 0.5% at rated output or less for 20Hz through 20kHz. Typical performance is 0.3% or less at 20Hz and 20kHz full power. Typical performance in the mid frequencies is 0.1% or less at full power. Output barrier strips provide taps for speaker impedances of 4, 8 and 16 ohms stereo or 2, 4 and 8 ohms mono. The terminal strips may also be connected for a constant voltage output of 25 volts in either stereo or mono, or for 70.7 volts in mono. The secondary of the McIntosh output transformer may be operated either grounded or not grounded. If grounding is desirable, a wire may be connected between chassis and common of either or both output termnal strips. An octal socket marked line output has connections for 70.7volts, 115 volts, 230 volts or 600 ohms for stereo 300 ohms for mono operation. The 600 ohm winding and the 300 ohm winding are balanced to ground. Pin 1 of the octal socket is the center tap for these windings and is grounded. Quote Link to comment Share on other sites More sharing options...
joshnich Posted June 6, 2008 Share Posted June 6, 2008 I have never heard the MC 275 so i cannot comment on it specifically. I have heard Mc 30s and MC225s on cornwalls and have to say they make a sweet combination one of the best quite honestly. Not tubby at all in the bass in fact pretty articulate and musical. It would be interesting to know if the MC275 is one of the originals - in which case it probably is in need of some work- or one of the later re-issues. Josh Quote Link to comment Share on other sites More sharing options...
joshnich Posted June 6, 2008 Share Posted June 6, 2008 Oh another question. Have you tried the preamp on another amp ? If not how do you know you like it and not the 275? I ask because I have tried some pretty highly regarded McIntosh tube preamps ( C22 and MX110) and found them both to be pretty dark and veiled I really really did not like them at all - and believe me I really wanted to like them! . I used them both with a MC225. I bought a Juicy Music Peach and the MC225 came to life. Before the Peach came I used the pre section of a MC6100 integrated amp and liked the way that sounded way more than the old tube pre's Josh J Quote Link to comment Share on other sites More sharing options...
fenderbender Posted June 6, 2008 Share Posted June 6, 2008 Lots and lots of variables.......Known factor, you are happy with the Cornwalls C220 sounds good with other amps?.....it's a very nice pre. The 275 is known to be the darkest of the mac tube amps and whats its state of repair???...if original 30+ years old and What tubes???? again , a lot of variables. the Mc30, MC 225, and MC 240 are reported sweeter sounding, if I were to go Mac tube it would be MC30 monos. Would I give up on the 275??? not right away I would see if I could try some different tubes or borrow a different pre from the dealer to see if it makes a difference. I think you need to be methodical and eliminate one variable at a time until you come up with the synergy you like. Quote Link to comment Share on other sites More sharing options...
fini Posted June 6, 2008 Share Posted June 6, 2008 Were the Corns networks rebuilt? I was thinking the same thing, Rick. Cheap enough to have Bob bring 'em up to snuff. Quote Link to comment Share on other sites More sharing options...
Daddy Dee Posted June 7, 2008 Share Posted June 7, 2008 Yup. That is an economical solution which may not address every concern, but really needs to be done anyway. Quote Link to comment Share on other sites More sharing options...
Audio Flynn Posted June 7, 2008 Share Posted June 7, 2008 Were the Corns networks rebuilt? I was thinking the same thing, Rick. Cheap enough to have Bob bring 'em up to snuff. Start at the very beginning its a very good place to start when you read you begin with ABC when you sing you begin with... Hate to sound like a broken record pun intended but I have heard my two best pair of speakers plus NOS Valves LaScalas experience amazing improvements from network rebuilds. Same goes for vintage tube amps. I would not make any further investments in amplification until the networks are rebuilt. Quote Link to comment Share on other sites More sharing options...
StereoTransmittedDisease Posted June 7, 2008 Author Share Posted June 7, 2008 Thanks for all the replies. OK To answer some questions: The amp is brand new... I believe version V. I have tried the pre with an old NAD Power Envelope amp and a Sanyo Plus Series mini-amp - both sounded fine. I do not have any other tube amps to try it with however. I have also rolled several NOS and used tubes with only small changes in the sound. I've tried GE, Mullard, Raytheon, Philco, Magnavox, Realistic Long Life, Zenith, new JJ Teslas, etc, etc. Right now I have some used Curtis Mathes 12AX7s in place along with NOS Mitsubishi 12AT7s with the same results - minor differences, but nothing to write home about. What I haven't done is to try the MC275 with another preamp; it just never occurred to me to do so. I have a trusty little single-tube Aric Audio preamp that I bought off of eBay a couple of years ago; I'll definitely try that out later today or tomorrow. As for the crossovers, rebuilding and refurbishing vintage speakers is sort of a hobby of mine. When I really like a pair of speakers I rebuild the crossovers at the very minimum. I’ve already ordered and received Sonicaps from Danny Richie of GR Research and Eichmann Cable Pods and matching spades from VH Audio. Now I’m just waiting on some 1/100 value Russian military PIOs that I won on eBay for bypassing. I would have bought the Sonicaps from Mr. Crites on eBay since he is more a part of the community here, but he didn’t seem to be selling the values that I needed – 2, 3, & 20mfd. Quote Link to comment Share on other sites More sharing options...
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