A long road traveled with the McIntosh MC-30

[Audible Nectar]

Travis: My "back cans" on the MX110 appear original. The center "multi-section" can (the important item) was replaced in 1989, and still works well. At the time of my most recent updating on this, the CE brand cans (mallory tooling) from AES were not available in that size, but are now available, so I will likely have that can replaced as a preemptive when it becomes convenient to drive it to Terry/Craig/other knowledgeable person. No shipping my MX110 due to glass on the face....

[Travis In Austin]

Travis: My "back cans" on the MX110 appear original. The center "multi-section" can (the important item) was replaced in 1989, and still works well. At the time of my most recent updating on this, the CE brand cans (mallory tooling) from AES were not available in that size, but are now available, so I will likely have that can replaced as a preemptive when it becomes convenient to drive it to Terry/Craig/other knowledgeable person. No shipping my MX110 due to glass on the face....

Don't you have a shipping box for that 110?

Travis

[paul cbc]

Allan,

I'd love the MX-110 manual if available.

Mine came without.

Paul

[Audible Nectar]

Well, well, well, a bit of a change here with the 30s, and it's a bit of "give and take".

It appears the caps have "bloomed" or "broken in", as the amps have become more detailed in sound - and less "forgiving". I thought these were approaching "SET land" when first paired......but I wasn't really prepared for THIS.

WOW is there ever a difference with the treble! They are more "open" sounding now, and very extended in the highs. Put a high quality recording (like a Mobile Fidelity Sound Lab disc) and they are glorious to an almost shocking degree. Put in an average recording, though, and they expose the flaws in that recording RUTHLESSLY. Edgy, older CD recordings sound VERY "old and edgy". So gone is the ability to smooth over an older recording, but gained is more extension and clarity, especially on the best recordings. These caps miss NOTHING.

The change came over the course of this last weekend (Thursday-Sunday)....so surprising I thought something was wrong. But after rolling in a different CD player hooked directly to the amps for a brief listen, then rolling the first 12AX7 to RCA and outputs to SED for another session, determined that is in the amps that the change is occurring. I was told by a few that these amps would likely change some after a 300-500 hour cap "break-in" (which I used to put little faith in), but have a whole lot more faith now.

After the "break-in", it seems that what few tube rolls I tried made much less difference. IOW, the RCA blackplate 6L6GC and the SED sound MUCH more alike than they used to - the differences are much more subtle. I consider that to be a good thing!

What is also interesting is that the first amp was rebuilt earlier than the second - maybe a 100-150 hour "lead" in hours used over the second. The change seemed to occur pretty much "in tandem", though - at least by the time I had noticed these changes, both amps "sounded the same" in an A/B test. I have run them a LOT over the past six weeks.

I specifically have kept tube rolling to a minimum, to better be able to observe audible changes in the amps as they "break in". It appears that they have, or are doing, just that. If I could "change them" in any way, it might be to make them just a slight bit less aggressive on the older stuff - just a bit smoother (maybe mix/swap one "smooth/laid back" cap in to settle them down some?), but all in all, I've gained more than lost in total. I wanted a set of these done on the bright/revealing side (as I have another set that can be done differently if desired), but it appears that I got a bigger helping of that than initially anticipated[]

[joshnich]

Well, well, well, a bit of a change here with the 30s, and it's a bit of "give and take".

It appears the caps have "bloomed" or "broken in", as the amps have become more detailed in sound - and less "forgiving". I thought these were approaching "SET land" when first paired......but I wasn't really prepared for THIS.

WOW is there ever a difference with the treble! They are more "open" sounding now, and very extended in the highs. Put a high quality recording (like a Mobile Fidelity Sound Lab disc) and they are glorious to an almost shocking degree. Put in an average recording, though, and they expose the flaws in that recording RUTHLESSLY. Edgy, older CD recordings sound VERY "old and edgy". So gone is the ability to smooth over an older recording, but gained is more extension and clarity, especially on the best recordings. These caps miss NOTHING.

The change came over the course of this last weekend (Thursday-Sunday)....so surprising I thought something was wrong. But after rolling in a different CD player hooked directly to the amps for a brief listen, then rolling the first 12AX7 to RCA and outputs to SED for another session, determined that is in the amps that the change is occurring. I was told by a few that these amps would likely change some after a 300-500 hour cap "break-in" (which I used to put little faith in), but have a whole lot more faith now.

After the "break-in", it seems that what few tube rolls I tried made much less difference. IOW, the RCA blackplate 6L6GC and the SED sound MUCH more alike than they used to - the differences are much more subtle. I consider that to be a good thing!

What is also interesting is that the first amp was rebuilt earlier than the second - maybe a 100-150 hour "lead" in hours used over the second. The change seemed to occur pretty much "in tandem", though - at least by the time I had noticed these changes, both amps "sounded the same" in an A/B test. I have run them a LOT over the past six weeks.

I specifically have kept tube rolling to a minimum, to better be able to observe audible changes in the amps as they "break in". It appears that they have, or are doing, just that. If I could "change them" in any way, it might be to make them just a slight bit less aggressive on the older stuff - just a bit smoother (maybe mix/swap one "smooth/laid back" cap in to settle them down some?), but all in all, I've gained more than lost in total. I wanted a set of these done on the bright/revealing side (as I have another set that can be done differently if desired), but it appears that I got a bigger helping of that than initially anticipated[]

David,

This all sounds very interesting. Your experience is intriguing to say the least. I have a pair of MC 225s that I have often considered having "the works" done to but have hesitated due to a weird desire to keep them original. Seeing your comment as well as Allans regarding his preamp update, makes me want to consider this again. You are right I cannot imagine ever selling my Macs so why not. If worse comes to worse I guess you could always take them back to original.

In my experience in every case where upgraded caps have been used (networks, other amps) the results have been dramatic so why wouldnt it be the case with a Mac.

Josh

[scott0527]

David,

This all sounds very interesting. Your experience is intriguing to say the least. I have a pair of MC 225s that I have often considered having "the works" done to but have hesitated due to a weird desire to keep them original. Seeing your comment as well as Allans regarding his preamp update, makes me want to consider this again. You are right I cannot imagine ever selling my Macs so why not. If worse comes to worse I guess you could always take them back to original.

In my experience in every case where upgraded caps have been used (networks, other amps) the results have been dramatic so why wouldnt it be the case with a Mac.

Josh

If you're going to use the piece, you can't keep it original unfortunately. The more vintage units I have rebuilt the clearer this becomes. The degree to which you change the original design and appearance can hurt the resale. However if they're professionally rebuilt, with proper respect to appearance and design, and you keep receipts as to who did the work and what work was done, resale can actually be held steady and sometimes improved. At least this has been my experience.

I've been meaning to get some pictures of the 30's Craig rebuit for me. They make my two pairs of original 30's sound dead. I had some new chassis made for these and Craig transplanted them along with a slew of new parts. They look and sound marvelous.

[Audible Nectar]

Another update......

Since these most recent posts, I have been running these amplifiers for 10 consecutive days now, in an attempt to fully settle the amplifiers into a consistent sonic pattern and complete the break in. This seems to have done some good.

While still very resolute and extended, they are much less "grainy/sandy/aggressive" sounding than they were at "bloom". They had a bit of a "surgical" feel to the detail at "bloom", but are now breaking into a much nicer "flowing" sound - albeit with all of the detail as before. These caps were a lengthy break-in.

These are NOT your daddy's MC-30s anymore. While still having much of the good attributes of the 30 (like the comfy lows, excellent midrange, and strength on acoustic music), it has become more "SET" sounding by the day. It is tube warm, but not "vintage" warm - like what MC-30 owners are used to warm (IOW, not rolled off). Even the SED 6L6 walks that detail line and natural presentation that harkens me to SET stuff. They are improving a bit with the lesser recordings, too.

I might still investigate a future "cap roll" to settle them down juuuuuuuust a smidge, but overall, I'm really liking the result of these. I had no idea the Macs would extend that much! Might be TOO much for some, but they are doing an awful lot "right"......and I can always have the second pair built on the "warm" side..........[] There's so much good in the circuit and transformer that goods will emerge with a wide array of cap choices - it's a matter of matching that to taste.

I wonder about dressing that second pair up with some reeeeeally good oil caps.......[:^)]

[NOSValves]

Tim,

I think you are fortunate to have a pair of 30's that are in such good condition. It seems from the absence of complaints/etc that yours are stable. Given what I know of those, they are as good of an original pair of 30's as I've seen. I wouldn't redo them until you get specific evidence or issue that shows they need it. Good working 30's with all original caps DO have an allure that you cannot duplicate if you change them. Mine did not hold up in that state, so I had to do something with them.

Do you have a Mac knowledgeable tech over there, or are you forced to ship here when you need service?

Yes my pair has been trouble free all the way, is very silent, looks and sounds great. So for now I am fine indeed. Gives me time to work on the other components of my set. [] Like the networks I mentioned, a new TT is coming up, etc.

I don't know a knowledgeable tech here, but I have not searched either. I'd hate to have these babies all packed up again and put into many stranger's hands, before they reach "the other side". I might just pay Craig, Terry or someone a planeticket to come and do it over here. [] Don't pack your deoxit in your handle luggage please! []

If anyone knows a mc tech in Europe, please let me know.

You pay for a vacation to Europe and I'll rebuild them totally labor free. That is a absolute no brainer on my part []

Craig

[NOSValves]

I've been meaning to get some pictures of the 30's Craig rebuit for me. They make my two pairs of original 30's sound dead. I had some new chassis made for these and Craig transplanted them along with a slew of new parts. They look and sound marvelous.

I was wondering how you liked them after using them a while. Glad your enjoying them. Those chassis were indeed a perfect fit I was impressed.

Craig

[NOSValves]

Another update......

Since these most recent posts, I have been running these amplifiers for 10 consecutive days now, in an attempt to fully settle the amplifiers into a consistent sonic pattern and complete the break in. This seems to have done some good.

While still very resolute and extended, they are much less "grainy/sandy/aggressive" sounding than they were at "bloom". They had a bit of a "surgical" feel to the detail at "bloom", but are now breaking into a much nicer "flowing" sound - albeit with all of the detail as before. These caps were a lengthy break-in.

These are NOT your daddy's MC-30s anymore. While still having much of the good attributes of the 30 (like the comfy lows, excellent midrange, and strength on acoustic music), it has become more "SET" sounding by the day. It is tube warm, but not "vintage" warm - like what MC-30 owners are used to warm (IOW, not rolled off). Even the SED 6L6 walks that detail line and natural presentation that harkens me to SET stuff. They are improving a bit with the lesser recordings, too.

I might still investigate a future "cap roll" to settle them down juuuuuuuust a smidge, but overall, I'm really liking the result of these. I had no idea the Macs would extend that much! Might be TOO much for some, but they are doing an awful lot "right"......and I can always have the second pair built on the "warm" side..........[] There's so much good in the circuit and transformer that goods will emerge with a wide array of cap choices - it's a matter of matching that to taste.

I wonder about dressing that second pair up with some reeeeeally good oil caps.......[:^)]

A small feedback bypass cap adjustment will cure what your describing. It's part of my standard upgrade for all MC amps no matter what coupling cap is used. The problem is not the HF extention it's a HF distortion acquired through feedback. Simple tack on mod and easy to reverse. It's best to use HF square waves to fine tune each amp while doing it but adding a 300pf silver mica paralleled over the existing bypass cap is a good starting point.

Man I have to quit sharing these little secrets Grrrrrrrrr []

Craig

[Audible Nectar]

Hi Craig.....was wondering if you were following along.......

I remember you mentioning this regarding DFlip's amps. I was going to ask you if this is just a "distortion eliminator" or does it actually "roll off" the high frequency response of the amp? I like the extension if it just gets rid of that little bit of edge they would be PERFECT.

I will say one thing - these caps are DAMN good. I'm hearing things out of these amps that's juuuuust jaw dropping[Y].

[Timmikid]

Well Wolfram was looking for a tech as well. If we find more European forummers, who knows what might happen. [] Craig's European tour!

[NOSValves]

Hi Craig.....was wondering if you were following along.......

I remember you mentioning this regarding DFlip's amps. I was going to ask you if this is just a "distortion eliminator" or does it actually "roll off" the high frequency response of the amp? I like the extension if it just gets rid of that little bit of edge they would be PERFECT.

I will say one thing - these caps are DAMN good. I'm hearing things out of these amps that's juuuuust jaw dropping[Y].

It reduces the HF ringing from the output transformer feedback and does not actually lower the HF response withing the effective range of your speakers. It's really a no brainer since it takes about 2 seconds to reverse. Try and see if you like it.

[Joe Auwen]

Craig,

Which caps are you bypassing in the MC-30?

Are you almost ready for the 'upgrade with whatever you want' pair of MC-30s yet..?

[ben.]

All very interesting...

BTW, Craig - do whatever the heck you want with that boat anchor that's been taking up space at your place. I have no idea when I'll get to devoting resources to it... Play around with it if you want - chuck it - rape it for iron - ebay it - whatever. If you want, I'll send you the 56s I got for it a lifetime ago...

[Audible Nectar]

This adjustment just took these amps into orbit!!!!

It's a funny thing - you don't really know what is missing in a system until everything "shows up" where it is supposed to be. EVERYTHING just fell into place. Now that things are in place, let me tell you of the improvements here....

These amps were never really "in sync" in any real sense......they have always been "just a bit off" from one another. I didn't really realize this until I got this adjustment done. On certain material (especially female vocals, but certain other recordings, too) it could be irritating to listen to - almost like there was a phase problem - but not in the usual sense of "out of phase". The most prominent feature of the sonic problems was that mid and high frequency "ringing", but there were these other problems I was attributing to the gear and room. There was also an occasional "boardiness" to the bass on certain material, but not always there.....and the bass was looser, I found out, than it was supposed to be.

After some long deliberation about Craig's post, and the realization that I did not want to incur any more risk of shipping these back to Joe and having these beeeeeeuuuuutiful babies damaged by couriers, I called Craig and he agreed to see me and my amps (a 420+ mile one way drive - the things we do for the love of gear!!). After doing the requisite voltage checks, Craig measured and did the necessary tweak, then had a mini-showdown on his system with the VRDs (which had the Macs doing reeeeeealy well and was a good comparison). But I really didn't understand the effect of this adjustment until I got them back home and into MY system.........

The result wasn't minor - it was OHMIGOD!!!!!!!!! Even the wives who have paraded through the home have noticed this within less than a minute of listening. The bass is deeper and tighter without "boardiness", and ALL recordings are listenable - and the good ones are REEEEEEALY good. The highs are smooth yet extend, the midrange is glorious, and all of this is happening with standard BEC AA networks. I can only imagine what's gonna happen once those V-Capped boards get here[]

I cannot get over how much this one adjustment fixed a whole host of little things in this system. It was always "My system's pretty good, BUT........". NOW, it's "My system is DAMN GOOD". Everything just fell into place.

Thanks a bunch, Craig - I owe you a BIG one.

[seti]

I am currently shedding gear piece by piece to get enough money together to buy a pair of MC30s. Hopefully I will have them by February or March : )

[kaiser SET say]

And now you know what caps to put in them right off the bat!

[NOSValves]

This adjustment just took these amps into orbit!!!!

It's a funny thing - you don't really know what is missing in a system until everything "shows up" where it is supposed to be. EVERYTHING just fell into place. Now that things are in place, let me tell you of the improvements here....

These amps were never really "in sync" in any real sense......they have always been "just a bit off" from one another. I didn't really realize this until I got this adjustment done. On certain material (especially female vocals, but certain other recordings, too) it could be irritating to listen to - almost like there was a phase problem - but not in the usual sense of "out of phase". The most prominent feature of the sonic problems was that mid and high frequency "ringing", but there were these other problems I was attributing to the gear and room. There was also an occasional "boardiness" to the bass on certain material, but not always there.....and the bass was looser, I found out, than it was supposed to be.

After some long deliberation about Craig's post, and the realization that I did not want to incur any more risk of shipping these back to Joe and having these beeeeeeuuuuutiful babies damaged by couriers, I called Craig and he agreed to see me and my amps (a 420+ mile one way drive - the things we do for the love of gear!!). After doing the requisite voltage checks, Craig measured and did the necessary tweak, then had a mini-showdown on his system with the VRDs (which had the Macs doing reeeeeealy well and was a good comparison). But I really didn't understand the effect of this adjustment until I got them back home and into MY system.........

The result wasn't minor - it was OHMIGOD!!!!!!!!! Even the wives who have paraded through the home have noticed this within less than a minute of listening. The bass is deeper and tighter without "boardiness", and ALL recordings are listenable - and the good ones are REEEEEEALY good. The highs are smooth yet extend, the midrange is glorious, and all of this is happening with standard BEC AA networks. I can only imagine what's gonna happen once those V-Capped boards get here[]

I cannot get over how much this one adjustment fixed a whole host of little things in this system. It was always "My system's pretty good, BUT........". NOW, it's "My system is DAMN GOOD". Everything just fell into place.

Thanks a bunch, Craig - I owe you a BIG one.

Dave,

No thanks required it was fun visiting and laughing with you and I owe you a few anyway!

This is a classic example of why I get so irritated when I read folks reveiwing gear that has not had an experienced technician that knows how to tune these old beasts. This is what happens IMHO, you tear out these 45 year old caps. We have no way of knowing what effect these caps had on the signal passing thru them 45 years ago I'm fairly sure in saying they were never what would be considered today as transparent. So you go out and buy modern caps and replace them throughout the signal path. In the case of a McIntosh you end up with a very incessive sounding beast much different then when it was fresh and new from the factory especially if you use those 50 cent cheapo caps. Dave had top notch Sonicap Platinuim teflon caps in his amps and the workmanship was absolutely spectacular!! (Pat Joe on the back top notch work) The amp simply needed tuning to make up for the raised effeciency and transparency of the new caps.

Joe why don't you give me a call on that project. If we wait for me to have spare time it will never get done!! Just send them and all the parts you want to use. In fact why don't you go right ahead and do your standard rebuild with whatever caps you like before sending them. I'll just tweak the other aspects and do what we discussed in the power supply.

[Deang]

"The highs are smooth yet extend, the midrange is glorious, and all of this is happening with standard BEC AA networks. I can only imagine what's gonna happen once those V-Capped boards get here."

I'm sorry Dave, and I really should have told you this up front: but after you put the new networks in you'll have to start all over and have the MC-30's rebuilt again with different parts until you rediscover the voicing you are now enjoying.[:S]