choosing a preamp

[bre's dad]

Many years ago I had a nice set up: C28, MC-2105, MR-74 but had to sell. I'm now looking for a new preamp and am considering something newer. I'm looking in the range of C32, C33 or C34. What are some of the fundamental differences in these? I've been told a C33 or C34 would be a better choice. Anything newer (unless it would be a steal) would be over budget. I'm wanting something newer than the C26, C28 era. Other gear this would be used with include an MQ-101, MCD-7008, restored ML-1C (or maybe my JBL 4411 which then the MQ-101 would go to whatever system the ML-1C's are on). I believe the C29 is from the same era as the C32 but I would like the EQ (spoiled by the one from my 4100 I just sold).

 

[twiiii]

The C-32 is marginal in signal to noise if used with high efficiency speakers and amps with.7 to 1 volt sensitivity with out volume controls. Had a customer that tried to use the 32 with Marantz power amps from that period. C-34 is a little quieter, its internals are more sophisticated, the distortion lower, but they sound pretty close to each other in my experience.

 

[bre's dad]

The C-32 is marginal in signal to noise if used with high efficiency speakers and amps with.7 to 1 volt sensitivity with out volume controls. Had a customer that tried to use the 32 with Marantz power amps from that period. C-34 is a little quieter, its internals are more sophisticated, the distortion lower, but they sound pretty close to each other in my experience.

my amp (for now) is a Denon POA-1500, rated 150 wpc. Speakers will be some ML-1C (about 88 or 89db or JBL 4411 (90db)

 

[jchouston]

I'm relatively happy with my C32, but it needs a going over as there is slight signal interference from sources and also there is a large gain difference when switching between EQ and NO EQ.

 

[greekgod]

The C33 has a reputation for being the most reliable and best sounding of those you have listed. After doing several months of research, I went with the C40. My 2nd choice would have been a C33. They are both very similar but for just a little more money, the C40 is a much newer unit.

 

[62caddy]

You may also want to consider the C 30 which has one of the quietest phono stages and does not have the built-in monitor amplifier section of the 32, 33 and 34 which helps to keep things simple.

 

[twiiii]

Greekgod. Tell me what you think of your C40 as compared to other pre-amps. Some folks say its not as clear as a 41 and 42. But I'll never have a pre-amp that doesn't have the graphic tone controls, a mode selector, a record selector and a input selector. Now I would really love it if the vol/balance/ mode were on remote control and the inputs have level matching. Why not make the graphic controls parametric so you can change the frequency for each control? I Don't really need the width of the control to be changed, but it would be fun. And to make things really cool, separate the controls to have left and right functions, so you could boost the Double Bass on the right and tone down the screechy violins on the left fir instance.

 

[kevzep]

I'm relatively happy with my C32, but it needs a going over as there is slight signal interference from sources and also there is a large gain difference when switching between EQ and NO EQ.

It must do, because you cannot hear any difference between EQ in / EQ out on my C32, Unless of course you have EQ applied........

The C33 has a reputation for being the most reliable and best sounding of those you have listed. After doing several months of research, I went with the C40. My 2nd choice would have been a C33. They are both very similar but for just a little more money, the C40 is a much newer unit.

Since researching the C32/C33 I have discovered they are quite different, and have different performance, the C33 has about 10db on the C32 in the noise floor, so that is definitely something to consider and quite significant....
Mine of course has been upgraded by Terry Dewick and has a noise floor more like the C33, I am sure glad about that, I was unaware of this when I was Preamp searching.....

I'm thinking of a C40 next because it has balanced outputs........and its newer technology which will match the MC352s performance...

So a stock C32 would be marginal, but if you send it to Terry for recapping and upgrading, it will extend its performance to a more competitive level.

 

[twiiii]

101 db is based on 2.5 volt operation, used at or below 1 volt sensitivity the noise factor becomes 90 db. With ML-1 rated at 85 db 1 watt you'll be fine, but if you were using klipsch Cornwalls Belles, Kornerhorns, JBL Paragon- Hartsfield or 4350, or EV Patricians, Georgians or Altec Valencia s, Seville s, A7-500 that range from 13 to 20 db more efficient that would reduce your signal to noise to 70 db, which would be unacceptable. Even using a Mac Amp with pre-amp the signal to noise would only be 80 db with at 1 watt, which would mean 25 db of noise at 4 ft distance from the grill cloth. That's why folks with efficient speakers want a new SS 100 watt Quad Balanced amp with 120 db signal to noise to get the noise level down to what you experience with ML-1's but experience a full range of Dynamics like the 2k or XR290 Mac speakers but with 1/100 the power. My speakers put out about 110 db with 20 watts, and my MC207 has about 112 to 115 db signal to noise, or about 102 to 105 below at 20 watts. So that means about 5 db of noise level from the speaker at 4 ft which can be heard with your ear a few inches from the grill cloth, 23 db noise, but not at my 16 ft listening distance, So I am safe. You should be very happy but others might not be.

 

[greekgod]

Greekgod. Tell me what you think of your C40 as compared to other pre-amps. Some folks say its not as clear as a 41 and 42. But I'll never have a pre-amp that doesn't have the graphic tone controls, a mode selector, a record selector and a input selector. Now I would really love it if the vol/balance/ mode were on remote control and the inputs have level matching. Why not make the graphic controls parametric so you can change the frequency for each control? I Don't really need the width of the control to be changed, but it would be fun. And to make things really cool, separate the controls to have left and right functions, so you could boost the Double Bass on the right and tone down the screechy violins on the left fir instance.

From what I read, most people seem to think the C40 is superior to the C41 and C42. However, I have only read about but not heard these other preamps so I can't really comment.

When I set the eq controls to neutral positions, the clarity certainly sucks. However, I discovered that if I turn the 10k control to the right, everything becomes MUCH clearer without any kind of harshness whatsoever.

The C40 has a reputation for being one of McIntosh's warmest sounding solid state preamps. It certainly is very warm sounding and also has the best bass I have ever heard. I still can't get over how amazing the bass is on this thing! However, I do think these qualities prevent it from having ultra clarity in the highs.

I got my C40 for $1600 including shipping and tax. I think in order to do better, you would have to spend at least $6000 on something like the C2300.
I have read that the C2300 has a clearer and more 3D sound than the C40 but I don't think I could ever give up the variable loudness control on the C40 which is amazing with headphones. The only way I would ever upgrade the C40 is if I were win the lottery and get something ultra high end from Accuphase or Burmester.

For the very advanced controls that you desire, I have no idea what I would recommend.

 

[kevzep]

101 db is based on 2.5 volt operation, used at or below 1 volt sensitivity the noise factor becomes 90 db. With ML-1 rated at 85 db 1 watt you'll be fine, but if you were using klipsch Cornwalls Belles, Kornerhorns, JBL Paragon- Hartsfield or 4350, or EV Patricians, Georgians or Altec Valencia s, Seville s, A7-500 that range from 13 to 20 db more efficient that would reduce your signal to noise to 70 db, which would be unacceptable. Even using a Mac Amp with pre-amp the signal to noise would only be 80 db with at 1 watt, which would mean 25 db of noise at 4 ft distance from the grill cloth. That's why folks with efficient speakers want a new SS 100 watt Quad Balanced amp with 120 db signal to noise to get the noise level down to what you experience with ML-1's but experience a full range of Dynamics like the 2k or XR290 Mac speakers but with 1/100 the power. My speakers put out about 110 db with 20 watts, and my MC207 has about 112 to 115 db signal to noise, or about 102 to 105 below at 20 watts. So that means about 5 db of noise level from the speaker at 4 ft which can be heard with your ear a few inches from the grill cloth, 23 db noise, but not at my 16 ft listening distance, So I am safe. You should be very happy but others might not be.

And this is why I am not obsessed with highly efficient speakers......
Mine are 91db, and my system is very quiet in terms of noise floor......

 

[MORTIS]

I'd love to have a C40. I've never actually heard one but I have great faith in its performance none the less. Its of the last generation of Mac preamps with a variable loudness, and with the 5 band eq its sound presentation is hugely flexible. The only thing preventing me from pursuing one is its lack of remote; I don't understand why Mac did that.
I can't help but wonder how much better it sounds than my C712... if at all (same generation). Everyone would assume it would of course sound better, but I'm not so willing to be convinced just because it cost so much more.

 

[ron-c]

C40 and C42 are closely related to C100 so these will be better than the other contemporary models.
C32 and C33/34 look the same feature wise but are completely different inside. C33/34 are the preferred choice.

Thanks,
Ron-C

 

[chef free]

You may also want to consider the C 30 which has one of the quietest phono stages and does not have the built-in monitor amplifier section of the 32, 33 and 34 which helps to keep things simple.

That is why I chose the C 30. You get the five band eq in a simpler package. No monitor amp, no separate record out, and no "compander". The C 30 is a bit pricey due to low production however.

 

[greekgod]

I'd love to have a C40. I've never actually heard one but I have great faith in its performance none the less. Its of the last generation of Mac preamps with a variable loudness, and with the 5 band eq its sound presentation is hugely flexible. The only thing preventing me from pursuing one is its lack of remote; I don't understand why Mac did that.
I can't help but wonder how much better it sounds than my C712... if at all (same generation). Everyone would assume it would of course sound better, but I'm not so willing to be convinced just because it cost so much more.

Not having a remote doesn't bother me at all because I listen to vinyl which means I have to constantly get up anyways.

I was originally going to get a C712 until I read a review that said the C40 had much better highs. I knew that if I got the C712, I would only end up getting the upgrade bug. But with a C40 I have no desire to upgrade anytime soon.

 

[kevzep]

C40 and C42 are closely related to C100 so these will be better than the other contemporary models.
C32 and C33/34 look the same feature wise but are completely different inside. C33/34 are the preferred choice.

Thanks,
Ron-C

Thanks for the information, I did some research and changed my post accordingly....


I am on the search for a C40 now.....:thmbsp:

 

[strat10]

I currently have a c-33 besides being a great pre-amp not having a remote makes me get off the couch and also makes my doctor happy excercise excercise!!

 

[kevzep]

I currently have a c-33 besides being a great pre-amp not having a remote makes me get off the couch and also makes my doctor happy excercise excercise!!

The no remote thing does not bother me either.........

 

[strat10]

I can also use my Squeeze box touch as a remote I love my c-33 definitey a keeper and matches well with my other solid state power amps.