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MC2100, MC225, MC240 advice needed

Alfmonster

Alfmonster

Active Member
I became obsessed with higher fidelity sound through Jazz - and I remember hearing for the first time the muted trumpet of Miles Davis on vinyl and being emotionally floored. It was on a really bad system, but that didn't matter - the music went beyond the sound quality and that was my gateway drug into this obsession. It felt like I was reading a great book from cover to cover with every record I played. And perhaps because I could not afford to collect first edition books, I began collecting first pressing records. And realizing that many of these artists are no longer with us, it felt like some sort of daily ritual of resurrecting them for the duration of the record...almost to remind myself everyday of their contributions to this life. So naturally I became obsessed with the possibility describing and articulating the sounds of these older performances and cobbled together a budget system on a shoestring budget.

Although the easiest option was to purchase a newer integrated amp via Amazon - like the Yamaha, I thought that for the same cost I could get a vintage McIntosh Amp (something I've for one reason or another lusted after for decades only as an object or myth as I had never heard one in person)

After some searching, I got lucky and ended up purchasing a McIntosh MC2100 via craiglist in great condition and have been quite taken with its performance.

I also purchased with the MC2100 a Yaqin ms23b in hopes of (fingers crossed) getting it modded to the LesMod at some point in the near future. Currently, I have my Thorens 166mkii (AT140LC cart and stylus) plugged directly into the Yaqin ms23b and then feeding directly into the MC2100 which is being played through a pair of Monitor Audio Bronze 2 speakers(bi-wired).

A couple things that I've found myself wrestling with is, do I need a preamp? I've been reading about its original mate the C26 and have also read how most people seem to really dislike it. I've also seen a c28/29 (c29 seems to be more stable than the 26 or 28) paired with it - and visually they look beautiful together.

Does anyone also directly feed their turntable into these types of McIntosh amps? and or have a similar combination of amp/preamp setup? And if so, do you have any opinions on the sound quality difference between direct vs through a preamp?

Also, while on this topic, has anyone paired a tube preamp with the MC2100 which in theory would be kind of like a much nicer or truer version of the what the newer MA252 was trying accomplish. I'm only listening to vinyl and I guess I find myself wondering if need a preamp or if the sound quality will improve considerably...or if I'm just goin to complicate things.

Is there a difference between prephono amps like a lesmod yaqin vs Project tube box, etc?

The final thing is, for those who have lived with an mc225 and an mc240 - is there a considerable difference? If I'm being honest, it was the MC225 paired with a Falcon LS3/5a that I originally wanted but the cost was just too much for me.

Thank you in advance for taking the time to read and respond. I hope this finds everyone well.
 
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Firstly, the output signal from a turntable cartridge needs to be both RIAA equalized as well as stepped up before the signal is useable by the power amplifier. So the short answer is no - turntable leads can never directly be connected to power amplifier inputs.

Nothing wrong with the sound of a C26 assuming it's been properly restored/serviced and performing as it should. In some cases, they have been known to exceed OEM spec by a considerable margin due the the improvements in replacement parts over those that had been originally available. I suspect those reporting poor experiences with the C26 are as a result of equipment that is in dire need of servicing or service work that hadn't been performed correctly.

I've never owned an MC225 so I can't comment on any sonic differences with the MC240. I do have an MC240 and found the difference between it and the MC2505 to be nothing worth talking about. If you really want a tube Mc preamplifier to use with the MC2100, the MX110 would be probably be the most affordable choice. Output impedances of the two units are absolutely compatible with one another. But frankly, I think you'd do just as well with a C26, MX112/113/114/115 (properly restored) which will not only be a lot more reliable than an older tube model, but sound every bit as good. C28 is a nice unit too but usually needs regular cleaning of the numerous pots in the signal path as this model had been so designed.

For the next step up from there, the C29, 30, 32, 33, 34 or C31, 35 & 37 if you want remote control.
 
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62caddy said:
Firstly, the output signal from a turntable cartridge needs to be both RIAA equalized as well as stepped up before the signal is useable by the power amplifier. So the short answer is no - turntable leads can never directly be connected to power amplifier inputs.

Nothing wrong with the sound of a C26 assuming it's been properly restored/serviced and performing as it should. In some cases, they have been known to exceed OEM spec by a considerable margin due the the improvements in replacement parts over those that had been originally available. I suspect those reporting poor experiences with the C26 are as a result of equipment that is in dire need of servicing or servicing that hadn't been performed correctly.

I've never owned an MC225 so I can't comment on any sonic differences with the MC240. I do have an MC240 and found the difference between it and the MC2505 to be nothing worth talking about. If you really want a tube Mc preamplifier to use with the MC2100, the MX110 would be probably be the most affordable choice. Output impedances of the two units are absolutely compatible with one another. But frankly, I think you'd do just as well with a C26, MX112/113/114/115 (properly restored) which will not only be a lot more reliable than an older tube model, but sound every bit as good. C28 is a nice unit too but usually needs regular cleaning of the numerous pots in the signal path as this model had been so designed.

For the next step up from there, the C29, 30, 32, 33, 34 or C31, 35 & 37 if you want remote control.
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This is great information! Thank you for this, I've started looking into the c28 from Audio Classics
 
Congrats on the 2100, a nice sounding amp.

Good advice in post #2&4 and I have a few additional notes.

Do you know the 2100's service history? An amp this old may require restoration work to sound its best even if seems to be working OK.

Since the Yaqin is just a phono preamp, I assume you're using the gain controls on 2100 as volume / balance controls. If that's working for you that might be fine but not really optimal. Adding a preamp will give you better control of volume and balance and add tone controls and other features and add the ability to hook up more sources beyond the TT - e.g. a CD player or a streaming thing or an AM / FM tuner.

Note that if you do get any of the mentioned McIntosh preamps, they will include a phone preamp section so you no longer would require the Yaqin or a Project Box. I cannot comment on the relative sound quality of the lesmod Yaqin vs Project tube box vs the phono section of which ever McIntosh preamp you get but I would be surprised if the McIntosh (again properly restored) was not as good or is likely better than the others.

Some of the older McIntosh preamps have issues with the volume controls that are very difficult to repair. I think (others please correct me if I'm wrong) this would apply to the C26, 27 and 28. If you get one of those, please insure that the volume control is working well even if you plan to have the unit otherwise serviced. Even the best service shops have difficulty with those volume controls. If you get one of those from Audio Classics, I recommend you ask about the volume control.

I also recommend that you hang out in the Turntables section on Audiokarma and generally learn techniques to improve the performance of your turntable. Proper turntable set up and care and cleaning of you records makes a very big difference in sound quality and performance.

Best of luck and have fun.
 
The c27 does not have the volume issues because the power on/off was relocated from the volume pot that the c26 and c28 use to a separate on/off push button for the c27. I have a c27 from Audio Classics that has been trouble free for years.
 
How are you powering the 2100 since it has no on/off switch and is on as soon as its plugged in? Even though these older MAC preamps have amplifier power switched outlets, I don't ever run amp power through the preamp and I would strongly advise against it.
Fortunately, I have several C28's which are able to use the SCR-2 speaker control relay accessory. The SCR-2 not only switches speakers, but also has heavy load power outlets and is designed to switch and carry the power load of a power amp. The C28 with SCR-2 were the proper lineup for an amp like the 2100 at that time.
Unfortunately, the SCR-2 is not compatible with the C26, but it does work with several other of the MAC preamps besides the C28.
I also don't have any problems with volume/on off knobs and they haven't been touched.
 
Agreed - the SCR is the way to go if you have the Mc preamplifier with the facilities to interface with it.
 
The volume control mounted power switch can occasionally fail because a plastic part inside cracks not excessive current draw. The C26 was not expected to be paired with a Mc2300, more likely a 240 or 250.

That said there are any number of 3rd party sensing power strips, some with staggered, delayed turn on, available.
 
c-dk: Thanks for the clarity on the failure point for the C26 volume knob. I don't know who mentioned the 2300 in this thread. I didn't.
All of the switched outlets on the back of these preamps have wattage draw limitations including the ones labeled for power amps. I would suggest they be adhered to including what you would consider a reasonable headroom reserve if you want to be conservative.
Your point about 3rd party power sensing strips is well taken.
 
TSmith8605 said:
Congrats on the 2100, a nice sounding amp.

Good advice in post #2&4 and I have a few additional notes.

Do you know the 2100's service history? An amp this old may require restoration work to sound its best even if seems to be working OK.

Since the Yaqin is just a phono preamp, I assume you're using the gain controls on 2100 as volume / balance controls. If that's working for you that might be fine but not really optimal. Adding a preamp will give you better control of volume and balance and add tone controls and other features and add the ability to hook up more sources beyond the TT - e.g. a CD player or a streaming thing or an AM / FM tuner.

Note that if you do get any of the mentioned McIntosh preamps, they will include a phone preamp section so you no longer would require the Yaqin or a Project Box. I cannot comment on the relative sound quality of the lesmod Yaqin vs Project tube box vs the phono section of which ever McIntosh preamp you get but I would be surprised if the McIntosh (again properly restored) was not as good or is likely better than the others.

Some of the older McIntosh preamps have issues with the volume controls that are very difficult to repair. I think (others please correct me if I'm wrong) this would apply to the C26, 27 and 28. If you get one of those, please insure that the volume control is working well even if you plan to have the unit otherwise serviced. Even the best service shops have difficulty with those volume controls. If you get one of those from Audio Classics, I recommend you ask about the volume control.

I also recommend that you hang out in the Turntables section on Audiokarma and generally learn techniques to improve the performance of your turntable. Proper turntable set up and care and cleaning of you records makes a very big difference in sound quality and performance.

Best of luck and have fun.
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Thank you for this @TSmith8605 ! I don't have the service history - although the guy told me it had been recapped which made me slightly worried. I made him play it for me and it sounded great and didn't blow up - so I took the gamble and have been playing it for many hours every single day since. The only thing I have picked up on is that a very slight buzzing sound coming from the power transformer box. Without a doubt, I maybe have to send the 2100 in at some point in the future to get it tested, serviced, and recapped.

I've been talking with Audio Classics and found a C26,C27, and C28 that they have already gone through, tested, restored and certified. I didn't even think of the c27 until I read it on this thread and now I'm down that rabbit hole. In my research for the c27, I stumbled onto Roger Russell's website and his write up of how he created the c26 - and his thoughts on the c27 which was really interesting to me:

http://www.roger-russell.com/c26pg.htm
http://www.roger-russell.com/c26pg.htm#c27

I love the turntable section! The people of the AK community have been so kind and patient with me in helping me set up and calibrate my Thorens.

Thanks so much for your response, it was really helpful.
 
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Gearjunky said:
The c27 does not have the volume issues because the power on/off was relocated from the volume pot that the c26 and c28 use to a separate on/off push button for the c27. I have a c27 from Audio Classics that has been trouble free for years.
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Thank you for replying to my thread and introducing me to the possibility of the C27! That preamp was not even on my radar until I saw your post on it. Can you comment on how it sounds comparatively to the c26 or c28? I could be mistaken, but I had read that there was a warmer sound with 26/28 -- but a quieter floor noise?
 
jcidave said:
How are you powering the 2100 since it has no on/off switch and is on as soon as its plugged in? Even though these older MAC preamps have amplifier power switched outlets, I don't ever run amp power through the preamp and I would strongly advise against it.
Fortunately, I have several C28's which are able to use the SCR-2 speaker control relay accessory. The SCR-2 not only switches speakers, but also has heavy load power outlets and is designed to switch and carry the power load of a power amp. The C28 with SCR-2 were the proper lineup for an amp like the 2100 at that time.
Unfortunately, the SCR-2 is not compatible with the C26, but it does work with several other of the MAC preamps besides the C28.
I also don't have any problems with volume/on off knobs and they haven't been touched.
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I had no idea about the SCR-2 speaker control relay - I looked it up and how does the hookups work for it? Currently I have my amp connected to a small surge protector that I switch on and off when I want to use it.

That is an amazing heads up for advising not to hook up the amp power to the preamp as I was actually planning on doing just that.
 
Alfmonster said:
Thank you for replying to my thread and introducing me to the possibility of the C27! That preamp was not even on my radar until I saw your post on it. Can you comment on how it sounds comparatively to the c26 or c28? I could be mistaken, but I had read that there was a warmer sound with 26/28 -- but a quieter floor noise?
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Impossible for me to compare, the only McIntosh pre’s I’ve owned/own are the c27 and mx110z. The c27 is a pretty bare-bones pre. I only use mine for streaming or movies. My TT goes through the mx110z.
I keep the tone controls flat and the variable loudness ‘out of the circuit’. I do this because I use a CR7 to control the volume so the c27’s volume knob is always at the 1-2 o’clock position. I run the c27 usually with a mc2105 and occasionally with my mc30’s. Both sound great.
 
Alfmonster said:
I had no idea about the SCR-2 speaker control relay - I looked it up and how does the hookups work for it? Currently I have my amp connected to a small surge protector that I switch on and off when I want to use it.

That is an amazing heads up for advising not to hook up the amp power to the preamp as I was actually planning on doing just that.
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The C27's main advantages over C26 are the better tracking volume control, improved C-Variable loudness circuit and last but not least, the separate power switch. Sound quality should otherwise be similar to the C26 on which it was based.

The C27 however lacks the facilities needed in order for the SCR2 to function. For that you would need a different model McIntosh preamplifier.
 
62caddy said:
The C27 however lacks the facilities needed in order for the SCR2 to function. For that you would need a different model McIntosh preamplifier.
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Would it be safe to say that powering an mc2105 or mc2100 off the CR7 is the correct method for on/off operation?
 
Alfmonster: thanks for the previous "thanks", but I did not write the post you quoted. I would think TSmith8605 appreciates your comments.
I think you have gotten several answers on your questions from others.
If you look at Roger Russels specs on the preamps, you will see the back panel information for each one stating what connections are there. If it says:" speaker control relay switch" then you can hook up the SCR. The C26 and 27 are missing this information.
The SCR-2 has 2 wires attached to it, one a very heavy gauge power cord and the other a thin control wire with a special 4 prong plug that plugs into the back of the preamp.. There are 2 power outlets on the SCR-2 box.
But as has been mentioned, it appears the C27 has lots of power switching capacity.
The 2100 consumes 450 watts for rated power and the 2105 needs 430 watts for rated power. If the C27 can switch 1800 watts and has a separate power switch, I would feel safe with that. I would not be doing this with my C28's without the SCR-2.
 
jcidave said:
If the C27 can switch 1800 watts and has a separate power switch, I would feel safe with that. I would not be doing this with my C28's without the SCR-2.
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No no no. It is the CR7 (remote volume control unit) that has the 1800W A/C outlet capacity. Not the C27 which is only 600W maximum combined.
 
62caddy: thanks for the clarity. I am not familiar with the CR7. I thought you might have typoed the C27 which is the unit the OP was talking about.
With 600 watts, the C27 should do his 2100 but I don;t think I would add anything else substantial to his switched outlets.
 
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