Tube Sound from A Solid State Mac Amp?

[Dave B.]

Some questions for anyone who has had experience with both tube and SS Mac amps:

Is there a Mac SS amp that comes close to the tube sound of an MC275 VI or MC2000? How would the MC452/462s compare with tube sound if driven by a tube pre, such as a C22?

If you were going to replace an MC275 VI or MC2000 with a Mac SS amp, which amp would you choose?

I've read some posts here about Mac "voicing" their SS amps. How does SS voicing compare to tube sound?

Is there a huge difference in the sound signature between Mac tubes and SS, or is it subtle?

Thanks for your insights.

Dave

 

[damacman]

Here we go again ... voicing ...

How does one voice the sound of neutral?

 

[Dave B.]

Okay, forget voicing! I never knew what those comments were about, anyway.

How would you answer my other questions?

Dave

 

[SaturationPt]

I would say that in guitar amps, where you're overdriving tubes on purpose for the distortion, ... huge difference.

In audio amps less difference, the whole idea is to be as neutral and transparent as possible. However, it is true that tube amps, especially tube-rectified tube amps, can have a certain "warmness" to the sound. That can be the type of distortion, or it can be the lack of the very high slew-rate of modern solid-state, or even the power supply design.

So I feel that the older McIntosh SS amps: 2505, 2105 (250. 2100) had more of a tube-like quality, a slow and soft feel to them that was more forgiving to mediocre recordings and softened shrillness where the modern amplifiers are more accurate and less forgiving. I haven't listened to McIntosh's modern tube gear and can't speak on its sound quality.

Speakers however, big difference in "voicing" there, the most colorative and influential part of the system IMO.

 

[Dave B.]

more forgiving to mediocre recordings

Thanks for your thoughts, Jeff. I've been around audio since the late '50s and I've noticed that as the "accuracy" of high fidelity has increased over the decades, the more I cringed at the sound of some of my more poorly produced LPs, CDs, and now even streaming files. I think you may be right about older Mac amps. The latest ones, the 452/462 era, are so refined that they are merciless on bad recordings.

Tubes can have a buffering effect on that mercilessness, IMO. That's why I was wondering what effect a tube preamp would have on a completely transparent amp like a 462. There appears to be favor among some on AK for a tube pre feeding a SS amp. If that's true, then I might prefer that kind of setup because of the relatively lower maintenance/higher reliability of a SS amp.

Dave

 

[Grenadeslio]

liked my MC2002, effortlessly powerful, but I wouldn't characterize it as tube like. my Belles amps have a similar kind of effortless power with just a touch more body in the midrange, Infinity Emit K's really sing on these amps.

 

[seacliffe301]

Tubes can have a buffering effect on that mercilessness, IMO. That's why I was wondering what effect a tube preamp would have on a completely transparent amp like a 462. There appears to be favor among some on AK for a tube pre feeding a SS amp. If that's true, then I might prefer that kind of setup because of the relatively lower maintenance/higher reliability of a SS amp.
Dave

That's certainly a potentially "sound" theory. (Like that double entendre?) But seriously, that would be worth taking a listen. Is there any way that you could audition a solid state amp, possibly from a dealer. Many a hi-fi aficionado utilize this very configuration. In all reality, it comes down to what pleases your ears.

I once owned an MC2505, which was 1st generation Mac SS. A very pleasant sounding amp, which I loved, but I don't know if "tube like" is the impression that I had of it. But then again I had been using a Dyna Stereo 70 and PAS3-X rig (all tubes) for a few years prior to the all SS McIntosh rig I had then put together. They were vastly different from each other.

 

[TSmith8605]

Some questions for anyone who has had experience with both tube and SS Mac amps:

Is there a Mac SS amp that comes close to the tube sound of an MC275 VI or MC2000? . . .

I'm having a hard time deciding if I like my MC275 IV or MC2505 (restored) better on the Maggies, 'stats, or OL Advents. Both have the clear, unrestrained and never harsh sound that I used to associate with the midrange of tube sound without the colorations at the frequency extremes that I also used to associate with tube sound (Dyna and Audio Research). The MC2505 does take a bit of the treble-region pain out of poor recordings on my 'stats which have no tolerance for that - the MC452 is clearer in that range and so (a bit) less forgiving.

. . . How would the MC452/462s compare with tube sound if driven by a tube pre, such as a C22? . . .

If you run the MC452/462 with a C22, you will get the sound of the C22. Note the C22 requires an amplifier with at least a 50kOhm input impedance (depending on the length and capacitance of the interconnect) and the MC452/462 both have input impedances of 22kOhm so the result might be rolled off highs. Using a short, low capacitance interconnect might be OK.

. . .If you were going to replace an MC275 VI or MC2000 with a Mac SS amp, which amp would you choose? . . .

I replaced my MC275 IV with an MC452 (although I still have the MC275) because my 'stats wanted more power (current).

. . . Is there a huge difference in the sound signature between Mac tubes and SS, or is it subtle?. . .

Subtle.

In my pre-McIntosh days, my perception was that tube electronics provided a clearer midrange with more correct timber and that better (e.g. ARC vs Dyna) tubes extended these qualities further towards the frequency extremes. SS electronics seemed to provide clear clean frequency extremes at the expense of maybe some harshness or a kind of glaze over the midrange and with less correct timber.

McIntosh amps of either type seem to have none of those issues so I've come to the point that I prefer SS since I don't have worry about maintaining the tubes.

Only thing is, I really need to hear some more modern SS and tube stuff. From what I've heard at shows, the extremely expensive stuff is good but too expensive. I would like to hear some modern Nelson Pass stuff or PS Audio in my system. I also am curious about all the love for SET, no-feedback class A amps like the tube versions or First Watt. Just what to hear some of that in the context of my system to see what happens.

Some people like the idea of tube sound as a buffer or filter for poor recordings. I'm not a fan of that idea. I have found that improving the source components helps a lot with poor recordings making them a lot more listenable without trying to hide things. (I recently bought two new turntables and the DACs in my C47 and MCD500 are a big improvement over prior sources I had). Replacing my 30-year-old VPI HW 19 / ET2 TT/Tonearm with a Rega P6 with the same V15 VMR/Jico made a surprisingly large difference in smoothness and quietness and tolerance for bad recordings even with the unforgiving MC452/ 'stats.

So if you have McIntosh electronics and are looking to make poor recordings more listenable, you might look at the sources rather than subtle difference between Mc amps.

The above advice is just my 2-cents and worth about that. YMMV.

 

[grillebilly]

I went from a 275 VI to a 452 for the same reason stated above. Probably the biggest upgrade I’ve ever done. Including going from using a receiver for a pre to a current model Mac pre.

 

[Dave B.]

These are the kinds of comments I was hoping to get. I appreciate the depth of what you all think about this issue.

audition a solid state amp, possibly from a dealer.

Yes. I'll be visiting Audio Classics soon and they have the 462 set up with some fine speakers in a good room.

If you run the MC452/462 with a C22, you will get the sound of the C22.

That's my thinking, too.

Note the C22 requires an amplifier with at least a 50kOhm input impedance (depending on the length and capacitance of the interconnect) and the MC452/462 both have input impedances of 22kOhm so the result might be rolled off highs. Using a short, low capacitance interconnect might be OK.

I have a C22 Frank McIntosh Commemorative and I can't find the output impedance figure anywhere. It's not stated in the manual or on Roger Russell's site. Does anyone hear know that number for my C22?

Subtle.

So if you have McIntosh electronics and are looking to make poor recordings more listenable, you might look at the sources rather than subtle difference between Mc amps.

I stream Spotify premium bitrate mostly and even with that I can hear badly produced recordings. I think you're exactly right about going to the source. "High fidelity" produces just that: high fidelity.

Dave

 

[SaturationPt]

A little off topic but as I think more about your question and how I’ve found a lot of the same inability to tolerate some of the recordings I used to love (your post #5) I’ve changed speakers.

When I had my early systems that were less accurate, some of those same-era recordings sounded great. As my system evolved (speakers first, as bright and accurate monitors became my preference) I found fault not only in the recordings, but in my sources and amplifiers.

So the amplifiers and sources had to evolve.

Still, the recordings that were flawed become more obvious, and less enjoyable. I doubled back to some of my vintage speakers that weren’t as revealing. I had an A & B speaker system for just this, some music sounds better on the vintage speakers.

I have since grown tired of having the speaker clutter, and have packed those back in their boxes and reverted to just my main system. I have a slightly EQed profile in my DSP to take some of the sharpness out of the music (just to taste) for those recordings and select the duller profile when playing that music (my wife is very sensitive to anything shrill, so it works for her also). I then select my flat-corrected profile on the DSP for the good stuff, and let ‘er rip.

 

[twiiii]

Some speakers are easily controlled by damping factor others are not. Speakers that are can be influenced by the SS macs with low damping factor to sound more like the tube amps. I heard Magico S5 driven by a 2301's 601's 1201's and the little 275 MK IV. The 275 sounded the most natural with reed and double reed instrument. When using Snell A7 Illusion I think I liked the 2301 the best. I had 275 MK I as new bi amping. They couldn't compare to a 3500 even at 1 watt levels. I thought the 3500 sounded better than the first series of Mac SS amps.

What I am trying to say different amps give different results with different speakers. You might love a MC 2205 with your speakers you may not and prefer Something else. Personally I can't stand 2205 with my speakers. reminds me in some ways of my 275's with sloppy bass. Only a 3500 can make my speakers and me happy when using tubes. My speakers loved MC 7200's and my current MC 207's. But thats my speakers. With your 1K's wanting to tame the highs and not needing a high damping factor for the bass maybe you want to try MC 501's. or a 402. 462 maybe a bit to revealing. For me it would be fun to try a pair of Audio Classics MC 3500's with a pair of IK's to see if that would tame them a bit. They also have the dreaded ARC and Luxman tube amps. But if you are serious about going SS you might want to try those MC 501's with a C-2200 pre-amp to mellow things a bit.

 

[sberger]

FWIW I've paired a C20 with a MC2105, driving AR3a speakers in a system that is used predominantly for vinyl but also see's a fair share of digital media. A beautiful, warm presentation, but not syrupy or flabby. Just an extremely pleasing presentation that can be listened to for hours(which it is).

 

[Dave B.]

With your 1K's wanting to tame the highs and not needing a high damping factor for the bass maybe you want to try MC 501's. or a 402. 462 maybe a bit to revealing.

I've matured some since my crazy days when I would listen at levels comparable to an F14's afterburner. These days I keep volume levels reasonable. My current setup has the MC275 VI driving the 1Ks. I have the MC2000 working AR9s (the big ones from the late-'70s-early '80s), which is my favorite combination. I listen to classical 99% of the time, piano solo and piano with orchestra mostly, although I do love big orchestral works such as Brahms symphonies and others, plus chamber works.

The C22-MC2000-AR9 sound is wonderful. Getting back to my main question, I'm wondering what a 462 would sound like in a C22-462-AR9 setup. If, as TSmith says above, the 462 would present the sound of the C22, then I might be persuaded to try that great amp. I hardly ever experiment with mix-and-match changes. Once I get a great-sounding setup, I stick with it. My 275-1K combo works for me nicely.

FWIW I've paired a C20 with a MC2105, driving AR3a speakers in a system that is used predominantly for vinyl but also see's a fair share of digital media. A beautiful, warm presentation, but not syrupy or flabby. Just an extremely pleasing presentation that can be listened to for hours(which it is).

I hear you, brother! That combination would ring my bell. My first system's speakers were AR3as, back in 1969. I got many years of enjoyment from them, although I was driving them with a Sony TA1120A integrated, which did a nice job. I'm an AR guy from way back. I'll bet your vinyl time with that setup is sweet!

I have since grown tired of having the speaker clutter, and have packed those back in their boxes and reverted to just my main system. I have a slightly EQed profile in my DSP to take some of the sharpness out of the music (just to taste) for those recordings and select the duller profile when playing that music (my wife is very sensitive to anything shrill, so it works for her also). I then select my flat-corrected profile on the DSP for the good stuff, and let ‘er rip.

Great use of EQ, SP! I sometimes wish we had an internal brain mechanism whereby we could think something like, "Raise mids +5 db" and our brain would modify the sound according to our thought's spec. Maybe Elon Musk is working on that right now.

Dave

 

[SaturationPt]

... maybe not direct from the brain yet, but you can do so much using a phone or ipad as a remote it's almost not necessary.

F14's afterburner? If you said F-100's afterburner you'd be old, but then my Dad doesn't even have a stereo anymore.

I do still have a TA-1130A around here somewhere if you need a trip down memory lane, pretty sure we can find an F-14 on youtube, ... S/N on that old Sony has probably dropped a bit though.

 

[62caddy]

I have the MC2000 working AR9s (the big ones from the late-'70s-early '80s), which is my favorite combination. I listen to classical 99% of the time, piano solo and piano with orchestra mostly, although I do love big orchestral works such as Brahms symphonies and others, plus chamber works.

The C22-MC2000-AR9 sound is wonderful. Getting back to my main question, I'm wondering what a 462 would sound like in a C22-462-AR9 setup. If, as TSmith says above, the 462 would present the sound of the C22, then I might be persuaded to try that great amp.

The AR9 is truly one of the great speakers from that company, or pretty much any company for that matter.

Unless the MC2000 is running out of steam, I'm skeptical the amplifier swap would amount to much.

 

[Dave B.]

pretty sure we can find an F-14 on youtube

I was on the carrier Intrepid in Vietnam and we had A-4 Skyhawks mostly. Watching flight ops is probably why I have to wear hearing aids. Even the A-4s' afterburners would make my chest cavity pulsate as they powered up for takeoff.

I do still have a TA-1130A around here somewhere if you need a trip down memory lane

I traded my TA-1120A for a Dynaco ST-120 and PAT-4. The 120 gave my AR3as a bit more punch.

The AR9 is truly one of the great speakers from that company, or pretty much any company for that matter.

Unless the MC2000 is running out of steam, I'm skeptical the amplifier swap would amount to much.

I couldn't agree more, Caddy. My MC2000 has plenty of steam left. I'm keeping it, for sure. I see that 2000s are being sold for as low as $7K. That's a great bargain if the unit is solid.

Dave

 

[W9TR]

I’ve had a couple of recent Mac SS amps - MC 601’s and I still have an MC 602. When I had them together I couldn’t really tell them apart. They sounded pretty much the same to me. My MC 275V has a sound signature that is easy to spot.

 

[twiiii]

See what I mean about different speakers and pairing. AR-3's are critically damped so SS Mac amps with low damping factor work great. In fact the designer of the AR-3 recommended using the Mod on the model 9 Marantz that would give the lowest damping factor possible approaching a ratio of 1. for best bass extension from an Ar-3. Mcintosh ML and XR speakers were highly damped so all the 2000 series Mac SS amps and their mates without meters sounded great. Its the synergy between the speakers and amp preamp combination that gives you what you want.

It was easier back in the day of great brick and mortar stores. You would try a 275 or a 2105 or if you had the space and coin a 3500 or 2300. maybe we would loan a big Marantz SS Stereo amp for a totally different sound. We loaned our demo and PA amps all the time. When we decided to get out of the PA business a gent wanted to try the 3500s. I guess he did as I was out of the country at the time. The two 275's and my 275's went that way also. People would try them and never bring them back. Same for the 2200's, 2100's and 2250's I owned.

I went through a lot of amps before settling on the Crowns and then the 7200's.

 

[TSmith8605]

. . .I'm wondering what a 462 would sound like in a C22-462-AR9 setup. If, as TSmith says above, the 462 would present the sound of the C22, then I might be persuaded to try that great amp. . .

Just to be clear, I was referring to the original C22, which I have and really like but (my point was) is noticeably more colored and noisy than current Mc stuff. You have a newer version C22 which I have not heard so my comment does not apply.

My comments about what the original C22 can drive were based on the following text copied directly from the operator's manual:

The MAIN jacks are fed from cathode followers. Longer cables than are normally supplied can be connected between the C22 and the amplifiers. The length of the cable is limited by the capacity of the cable. The total capacity must not exceed 1000 mmf. For instance: cables with a capacity of 25 mmf per foot may be 40 feet long; 13.5 mmf per foot cable may be 75 feet long. The input impedance of the amplifiers should be 50,000 ohms or greater.

. . .I have a C22 Frank McIntosh Commemorative and I can't find the output impedance figure anywhere. It's not stated in the manual or on Roger Russell's site. Does anyone hear know that number for my C22?. . .

Nor do I know if the C22 CE can drive lower impedance inputs on the newer amplifiers but I note that the MC2000 unbalanced input impedance is 20k which is very similar to that for the MC452/462, so if your C22 CE works with the MC2000, it should be OK with an MC452/462. You could call or email McIntosh to verify.