Ultimate Advice MC2300/MC2500/MC2600

[CountD]

Actually sold MC2255s against all these amps back in the day. Had to listen to them and absorb customer feedback and their votes via their checkbooks. MC2300 was noisier than the others and many came in on trade, MC2500 and 2600 were quieter but still noisy compared to MC2255. The MC2255 seemed much more dynamic compared to the others even though it would not play as loud as the others. Really liked using MC2255s and MC7270s in a vertical biamp.

This is true. The 2255 (or 2205) is a bit more dynamic, but it seems to me that the 2300 has endless power. I feel when I turn it up, it keeps on going. The 2255 is a true masterpiece, the end of the chrome chassis, everything that Mc is about, the cleanest Ron Evans design, and very robust. A standard so to speak.

If I were on an island and had to choose between the 2300 and 2255 it would be a tough choice. I would probably choose the 2300 because I know the power supply could power every other appliance I owned, including the washing machine.

 

[c_dk]

I had two customers who drove McIntosh XR19s with mono blocked MC2500s and with dedicated 20 amp services to each it was awe inspiring when they were pushed. Both chose the first MC2500 for the sheer power and then felt the need to go extreme by adding the second.

When going to this level all parameters needed to be stepped up... from finding turntables that would live in the enviroment, insuring proper AC, even Blue Tacking pictures and figurenes that would rattle and dance around on shelves.

When we first started experimenting with passive biamping in the late '80s there was just something magical when when making use of the biwire capability of the Vandersteen 2cs and B&W Matrixes. While the MC7270s were overkill for the 'steens, the vertical biamp solved the ongoing issue of the 3 ohm nasty phase angle of the B&W mid driver.

 

[motorstereo]

Wow would I love hear a set up like that. I can just imagine the bass would be rattling everything in sight.

 

[hammr7]

One 2500 is more power than most of us need. I know, as I have one. It will shake my house and rattle my windows (and make all my neighbors notice I'm around, even with my windows shut!).

All three units in this thread are awesome, and in reality, in the right shape and at the right price any one of them would make any of us quite happy. Except for one thing .... they are really heavy. I rarely use my 2500 any more because I don't have a good cart to haul it around, and it weighs 130 Lbs. Plain and simple, I'm getting too old to handle this beast. I have lesser (power) McIntosh amps I can use instead, a 2105 and a 2250. Half the weight of the 2500, and I rarely miss the extra 3 - 5 dB.

 

[Dylanl]

I have not been on the forum for a while but this is a very interesting thread. I have a 2300 and also find it to be very warm and musical with loads of power. I would like to hear a 2500 but over time I have read it sounds a little less involved. Anyone close to Pittsburgh, PA that want to listen and compare let me know.

 

[ron-c]

The best model out of the bunch? The one you have at home of course.

Thanks,
Ron-C

 

[Dylanl]

I would love to do an A vs B. If anyone is close with a 2500 send me a PM please.

 

[jdwk]

I had two customers who drove McIntosh XR19s with mono blocked MC2500s and with dedicated 20 amp services to each it was awe inspiring when they were pushed. Both chose the first MC2500 for the sheer power and then felt the need to go extreme by adding the second.

When going to this level all parameters needed to be stepped up... from finding turntables that would live in the enviroment, insuring proper AC, even Blue Tacking pictures and figurenes that would rattle and dance around on shelves.

When we first started experimenting with passive biamping in the late '80s there was just something magical when when making use of the biwire capability of the Vandersteen 2cs and B&W Matrixes. While the MC7270s were overkill for the 'steens, the vertical biamp solved the ongoing issue of the 3 ohm nasty phase angle of the B&W mid driver.

so what kind of turntable did they have? You have intriged me. I hope they at least had a large room. I only have the 2205 and xr 7's and I can get it so you can clearly hear all the lyrics on a hard rockin song outside the house with all the doors and windows closed.

 

[c_dk]

Believe it or not one was a Mitsubishi DP-EC20 with at first an AT-32 MC and later one of Gordon Gow"s prototype McIntosh moving coils. I was shocked at how well those old Mits autos lived in a high volume, high bass output enviroments. He insisted on a auto and with low compliance coils the Mits worked OK. Tried my best to swap him up to a TD126 with a SME3009 but failed.

Can't remember the other table... will have to pull out old customer data sometime...

Both were voiced with MQ107s as was my practice and easily covered the 16 Hz pipes when testing with the Tocatta or the Organ Symphony, as long as you used a turntable.

 

[damacman]

I'll revive this one - heck, I joined because of it. I've owned about ten MC2300s, still have two presently. I've also owned one MC2500 - lusted after 'em for years and finally came across the opportunity to trade David Yo (remember him?) out of a gorgeous one with a black face.

For a long time, I ran strapped MC2300s to my Altecs (9846-8As). It was way awesome. I picked up that MC2500 about a year after I began doing that. It was hit or miss and had a sound unlike any other McIntosh amp I had ever heard. So, I took it in to be analyzed by my friend Chris Horton, then employed at Custom Sounds in Little Rock - it passed with flying colors and exceeded all specs. I played and played with it with the Altecs but the strapped MC2300s were in a whole 'nuther league. So, I compared a single versus the MC2500, again I preferred the MC2300 in all areas.

As I resigned myself to sell it, my friend ask to borrow the amp. So, I took it over to his place and we connected it to his XRT-20s. With a stable platter Pioneer CD player connected directly to it's inputs, and using the gains as our only means of adjusting volume . . . it was unbelievable. Remarkable. Breathtaking. We had never enjoyed his XRT-20s so much. Unfortunately, the very next night, the exact same set-up was like a total 180.

Shortly thereafter, I sold it. I've compared many Mc amps to my trusty MC2300s - both tube and solid state. Those with Power Guard and without. The MC7270 was about the next best thing I heard.

Now, having said that. I've never owned a MC2600 - although I've lusted after that amp for as many years now as I did the MC2500. So, who has one in the Phoenix area that would like to compare to either of my MC2300s? If I could JUST get that out of the way, I would definitely be able to rest more peacefully . . . unless of course the MC2600 was indeed the cat's meow.

And, I love the George Jones / George Strait racks. They use those amp for a reason!

 

[MX117.MC7150]

First choice to run a set of L300s would be tubes. Pair of MC30s or MC60s would be best, followed closely by the MC275. If one must have solid-state, then MC50s first or MC2105 if a stereo amp. Am saving my change for a pair of L300s. Some day.

 

[hwirt]

So, I took it over to his place and we connected it to his XRT-20s. With a stable platter Pioneer CD player connected directly to it's inputs, and using the gains as our only means of adjusting volume . . . it was unbelievable. Remarkable. Breathtaking. We had never enjoyed his XRT-20s so much. Unfortunately, the very next night, the exact same set-up was like a total 180.

I don't understand why the same amp with the same speakers would sound "unbelievable" one night and terrible the next?

If you like the sound of the MC 2300 why not just stick with that, It has more than enough power and matches up very well with all the JBL L series speakers. I used one of my MC 2300 to drive my L100's and L220's for years and never experienced a driver failure even without the Power Guard circuits. Tried connecting the MC 2300 to a friends pair of L300's and the combination was great!.

Also the McIntosh solid state amps using output and or auto-transformers work well and are generally considered the best sounding McIntosh amps. I have never experienced any anomalies with any of my McIntosh transformer coupled amps, just pure musical bliss.

 

[hwirt]

The autoformers with McIntosh solid state cause rhythm & pace to be off, additionally the solid state amps with autoformers tend to be very bright sounding,IMO.

With rhythm a pace both being timing issues I would suspect the turntable or digital transport as the source of the imperfection, unless of coarse the amplifier is moving rapidly through warped space-time. And for the record I prefer accurate honest sound, dynamic and free of distortion and as close to the original recording or performance as possible.

 

[hwirt]

I'm not alone in my thoughts. Signal amplification does effect rhythm & pace, it's not just a source/other issue. What works on paper does not necessarily work in real life. I've always audtioned components with my ears & not my eyes, but that's just me.

Forgive me, I didn't realize that this was the Thinking Out Loud forum and was trying to stay with the facts as much as possible.

"When you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge of it is of a meager and unsatisfactory kind; it may be the beginning of knowledge, but you have scarcely, in your thoughts, advanced it to the stage of science."

Sir William Thompson, Lord Kelvin (1824-1907)

 

[damacman]

Interesting commentary about the Autoformers / Solid State. But it isn't true. How do I know? I'll tell you.

While I was the Proceed rep in North Texas, I made a trip to the Madrigal factory for product training (this would have been in 1999 - I still have the certificate of completion). At dinner on the first night, I sat next to a gentleman that had apparently been with Madrigal for a very long time, and even before that was employed by Mark Levinson himself from what sounded like to be almost the beginning. He and I got to talking and he asked me about how I got into the audio business and I explained my fetish with McIntosh gear, etc. Imagine my surprise when he tells me, "I have a McIntosh MC2300 and I still use it on occasion!" Wow . . . when I asked him how he came across it, the story he shared with me was pretty cool!

Obviously, in the 1970s, McIntosh had a huge foothold in dealers. According to this gentleman, Mark had intended to demonstrate to dealers why putting a transformer of any kind between the output of a solid state amplifier and the loudspeaker was a bad idea. They obtained a MC2300, I'm assuming because of the power capability of the Autoformers, and removed the Autoformers from the amplifier. They connected them to one of their early offerings (I forget which ML model, sorry) in the lab to hear the results for themselves.

At about this time I responded, "I've never heard anything about this before." His response was, "That's because we could not hear a difference."

True story. Apparently, he later obtained the amp for personal use for his band and had been using it on occasion ever since.

I've owned a few MC2002s in my time . . . I direct comparisons with the MC2300, I never noticed any of the things reported here.

 

[damacman]

I don't understand why the same amp with the same speakers would sound "unbelievable" one night and terrible the next?

I really have no idea. For some reason, that particular amplifier was kind of like that. It was hot and cold. I'd certainly be open to listening to another.

If you like the sound of the MC 2300 why not just stick with that, It has more than enough power and matches up very well with all the JBL L series speakers. I used one of my MC 2300 to drive my L100's and L220's for years and never experienced a driver failure even without the Power Guard circuits. Tried connecting the MC 2300 to a friends pair of L300's and the combination was great!.

For the most part I have. I ran the strapped MC2300s for about five years in all. I may migrate back to that one day if I can find another MC2300 at a fair price. They've gone through the roof as of late!

 

[hwirt]

Interesting commentary about the Autoformers / Solid State. But it isn't true. How do I know? I'll tell you.

They obtained a MC2300, I'm assuming because of the power capability of the Autoformers, and removed the Autoformers from the amplifier. They connected them to one of their early offerings (I forget which ML model, sorry) in the lab to hear the results for themselves.

At about this time I responded, "I've never heard anything about this before." His response was, "That's because we could not hear a difference."

.

Great story damacman, and the result does not surprise me. :thmbsp:

 

[damacman]

So, time to revive this one in hopes that someone will chime in with commentary on their experience with the MC2600. Bueller? Bueller? Anyone?

 

[Rich Andrews]

The 2500 and 2600 are nearly identical in basic form. What McIntosh did was to install more outputs, etc. There were some changes made on the driver board as well. The internal routing of the fan wiring was also changed. All of those changes reduced the noise floor and distortion. Balanced inputs were also added to the MC2600.

Adding balanced inputs to the MC2500 is almost trivial.

I took the small changes that were made to the MC2600 and applied them to my MC2500 amps. I did not change the output circuitry. I felt that the difference between 500 watts and 600 watts was not worth the expense. Now my MC2500 amps meet MC2600 specs except in power output.

There are two basic flavors of MC2500. The early silver faced and the later black faced. It is the later black face that I am comparing to the MC2600. The earlier silver faced amp is different than the later version and has a different schematic so modifying an early MC2500 will be more challenging.

I have never heard any sonic aberrations from any McIntosh amp that has autoformers. I suspect that if someone experiences anything it is due to the speaker load affecting the output transistors and thus frequency response in a non-autoformer equipped amp. The autoformer presents a nearly perfect load for the output transistors regardless of speaker load and thus the amp is unaffected by speaker load.

 

[twiiii]

The are many ways to look at this question, I want to look at your speakers first. I checked JBL's specs and they say 300 watts. What type of watts, peak watts, RMS watts. If you don't understand the speaker, How do you know which amp is best. Then there are the amp issues. A 2300 is nothing more but a 2105 with more devices, 2 fans and a larger power supply. The 2500 is a larger 2255 as a 2600 is a larger 7300. Some folks as expressed don't like the 2500 because of Power Guard. They can't get the edge of a 2300, the distortion, they like. But the 2500 has the second gen Power Guard which was much improved over the 2205. The 2300 is more forward than a 2500 and for Altec JBL EV and professional Klipsch, Cerwin Vega, that's not a good thing. I used 2500's and 2600's in systems I installed running big 18" and 16 ' woofers and they gave great dependable service in adverse conditions a 2300 would self destructing annually. I admit home environment is different, but when pushed hard 12 hours a day in smoke filled and dirty filthy atmospheres, the 2500 and 2600 were real troupers. I would say I preferred the laid back sound of the 2500 and unlike the 7300 the 2600 had the reserve a 7300 lacked. Though the midrange and the tweeter are padded down close to 12 db to match the woofer, to much distorted power could destroy drivers. So I would throw out the 2300 with the baby's bath water. The woofer is the weak point here being asked to cover clear up to 800 hz. If were crossed lower say 250 and had a mid woofer like larger JBL's with the same tweeter and mid I'd feel safer. So maybe you want to get a 2500 or a 2600 and connect to the 4 ohm tap to lower the voltage increasing the dampening factor and better match of the power to the speaker, but that would be a 2255 wouldn't it. We ll not quite because the Power Guard would wait for the wave form to distort which would be closer to 600 watts+ divided by less than 2 on the 2500 hundred and over 700 watts divided by less than two with the 2600. I think you should be happy with what you have. If you want real improvement look for a MC352 or MC 402. Then you'd be much happier. Their great current reserve and fully balanced operation would give not only much more umph, but a quality the other amp's can only dream of! The signal to noise ratio improvement of close to 20 db is worth its weight in gold to give you that dark black background to base your listening experience on. Its similar to listening to a Mcintosh MC7005 player and a McIntosh MCD 500. I know I've l owned both. You should try going from 2200 to 7200 to 207 like I have, you can't believe the evolution in sound. You really can't appreciate some of the differences into days source material without the upgrade in amps. Just going bigger is not the answer you have to go for quality now.