McIntosh MC275 MK VI Clone

[CohibaJoe]

What do you do with a slush fund >4K...Buy a McIntosh MC275 IV Clone. Was on AliExpress last month on picking up some PCB boards, switches(testing) and came across Clones of well know gear. After IM'ing on details, I purchased Orsefon MC275 (McIntosh MC275 clone). Going over the pictures and asking many questions...$2200 and 3 weeks later we have an Amp. The circuit is based on MC275 IV.

1. 4-KT88, 3-12AX7, 4-12AT7...EH KT-88, 12AT7/12AX7 got me? LED Monitor lighting
2. Tube sockets bolted on separate metal board to prevent PCB cracking from Tube solder mounted sockets with Tube heat dissipation pipes.
2. Auto-BIAS system
3. System is monitored and Shut's Off (Relay Controlled) if Over-Volts, Clipping and Tube fails
3. Hand soldered WBT Silver
4. Gold Plated PCB Trace board
5. WIMA Films, Siemens Resistors, Nichicon, Rubycon, Philips Caps
6. XLR Balanced signal input (requires preamplifier drive)
7. RCA analog signal input (no need to drive by the preamplifier)
8. Mono output mode/stereo output mode
9. Balanced input selection/unbalanced (RCA) input selection
10. Left/Right channel volume adjustment (only for RCA analog input mode adjustment)
11. Output resistance group: 4 ohms, 8 ohms, 16 ohms
12. Gold Plated 5-way terminals
13. 1.75mm Gold Plated housing
14. Output power: stereo mono 75W / mono bridge method 150W
15. Coil 16 layers (the original Mcintosh MC275 is 12 layers) UP-OCC (single crystal oxygen-free copper) group cross winding method with the purity of single crystal oxygen-free copper 99.99%
16. Unit weight 68lbs (Yes, it is as I had to go up to 2nd floor)

Unit is running 10-12hrs per day (currently 30hrs) and I have to say...WOW. I cannot hear any "Hiss" from the tweeters and Transformer hum nothing (maybe if I had Dog hearing). After 20hrs the unit has Opened up...WIMA will need 100+hrs. I have ordered from Jim McShane a set of MC275 tubes ( 4 KT-88 Genalex Re-Issue, (3) Tung-Sol ECC803S/12AX7, (1) Genalex B759/12AX7, (4) CV4024/12AT7 Mullard NOS).

 

[Mdpaudio]

Do the transformers have all the same windings as a real McIntosh? The transformers are very complex and are required for the real circuit to work.

 

[CohibaJoe]

Here is a REAL Mac part that I ordered from Audio Classics....Name Plate

 

[rustnrot]

It would be very interesting to see if this meets the specs of the original.

Thanks for the inside pics. I wonder if you can just buy the output transformers?

Another take is my Unity Coupled Amp https://audiokarma.org/forums/index...rveen-vdv-1070-uc-output-transformers.937649/

Buckle up your seat belts folks, as this thread will be long, delve into morals, politics, world affairs, copyrights, trademarks, etc. Like this one:

https://forums.stevehoffman.tv/threads/thought-id-seen-it-all-chifi-amplifier-clones.1105573/

 

[62caddy]

Where do you go when it needs repairs?

 

[gadget73]

With Mac gear its definitely about the transformers. They are very unique in how they are wound, and without that same winding method its just not going to act like the real deal. The rest of it can be copied easy enough, its just passive bits and the schematics are out there. Just looking at the pics, it looks pretty good. If those are all genuine parts rather than re-brands it looks like a nice piece.

Also not interested in getting into geopolitical debates but its most definitely possible to get quality stuff from China. The manufacturers are well established at this point and capable of excellent work, its all in what you want to pay for. QC costs money.

 

[Pio1980]

If the UC patents have expired, they are then, afaik, in the public domain, and it's then a matter of QC.

 

[gadget73]

Well, even if they aren't expired it might be awful difficult to enforce.

Its an old enough tech that it is quite likely expired at this point. Pretty sure I've seen stuff dating to the late 40s about it.

 

[trainbuftony]

Now performance test it next to an original.

I'd honestly love to know how close they came and I don't have any expectations.
I think it's very possible for them to wind McIntosh transformers if they want to.
If they hold the design and the brand to the same esteem that American Audiophiles do, then what are the chances that they actually tried to make a faithful tribute piece?
Its entirely possible that it is as good or better than the original article strictly from a performance standpoint.
Inquiring minds want to know...

 

[CohibaJoe]

Where do you go when it needs repairs?

I based my purchased on "What if the Sh*t hits the fan, 2K wasted, Let's see what is has and I LOVE to see the comments from the Mac community". The suppler provides support and replacements of parts "If/When" required.
I have a Tech (Yes...sometimes you need a little help) that works on Tube, SS...I call him the "Scotty" of Star Trek. I would classify this an Curiosity purchase and look forward on providing updates (so far 1 week ). I have talked to my local Audio shop (going 32yrs)
on demoing once I have 200hrs.

 

[damacman]

IMHO, a thread as this has no place on AK. Praising a design clearly stolen from a US based manufacturer is .... well, good for you.

I respectfully ask @Mike Gibson to remove it.

 

[gadget73]

Why? Pretending a thing doesn't exist doesn't make it not exist. Trust me, I've been trying that for years with all sorts of problems.

 

[rustnrot]

Hopefully your Tech can measure power output and distortion, looking forward to the results.

Quick question: Did it come with a Tube Cage?

Can you get it with a Chrome Chassis--asking for a friend...

 

[62caddy]

The suppler provides support and replacements of parts "If/When" required.
I have a Tech (Yes...sometimes you need a little help) that works on Tube, SS...I call him the "Scotty" of Star Trek.

Do they provide a schematic or will a McIntosh MC275 Mk VI schematic suffice?

 

[empirelvr]

This is an interesting situation. Nothing in the amplifier is proprietary anymore (Patents last for twenty years, so the transformer design is in the clear and the original patent is easily obtainable on the net: https://patents.google.com/patent/US2477074A/en), the circuitry is not a secret (schematics everywhere), things like knobs, binding posts, RCA jacks etc are just widgets, and I don't think McIntosh has a copyright on the physical look and design of their products. (It is possible to do so, but I can't find a mention if McIntosh has ever done that.)

Nowhere on the unit does it say McIntosh, and it isn't being represented as a genuine McIntosh. It also looks to be well made.

So I'm not sure you can say it's necessarily stolen. Bad faith? Yes. Sleazy? Definitely. But is it actually breaking any laws? Unlike...say...when in the early 1980's certain shady stores were flooded with cassette tapes by "KDK" that looked exactly like TDK products and were absolutely an attempt to fool people into thinking they were buying TDK tapes, there appears to be no attempt to make you think you are getting a real Mac.

How different is this to the classic car kits that are available? (And I'm really asking. I know they exist but nothing else about them.)

As they say, imitation is the sincerest form of flattery. And by the looks of it, this unit is very flattering!

Hmmmm...

 

[62caddy]

How different is this to the classic car kits that are available? (And I'm really asking. I know they exist but nothing else about them.)

Certain car parts do have be licensed to be reproduced, ie, logos and trademarked nomenclature. Repro body panels by unlicensed manufacturers to my knowledge have to be made slightly out of OEM spec and don't fit well resulting in body gaps wider than normal.

 

[Lavane]

Congrats, it's a nice looking amp. I do like the way the sockets are installed, using those rings to put all the stress on the chassis. It does look well thought out with quality construction. I don't get the frowns about it being a clone. There are plenty of Dynaco clones out in the world and still being produced. Original design and modified. The Dynaco brand is still being used to produce a version of the ST-70. The patents have expired on that MAC. This amp is based on the MC 275 MK lV, but not exactly. The output transformers are a bit different, and probably a few other small changes as well. I just don't see a problem with someone producing an old design. Lots of people build clones of popular older designs. I bought a ST-35 clone because I wanted a fresh new amp instead of an original version that would need rebuilt on top of the initial cost of the amp. There is plenty of room in the world for those that want restored original, or a new clone. If If wanted a MAC 275 MKlV, I would look damn hard at the Orsefon 275. That being said, stealing designs of equipment with active patents is just wrong.

 

[grillebilly]

I dunno. Just because everyone else is doing it doesn’t make it ok.
The case for it being perfectly legitimate is tough to argue against but I still get a little creeped out by it being a direct copy sans nameplate.
Carry on.

 

[gadget73]

personally I'm really curious if its all hat, no cattle or a legitimately good piece of gear. Until then I'm reserving any judgements beyond saying it looks good in pictures.

the morality of whether or not its cool to make what is pretty clearly a clone of a more well known piece of gear is a swampy discussion that doesn't really have a useful conclusion either way. I want test results.

 

[David_NC]

It looks like a nice amp. I'd be interested in hearing how it performs and sounds compared to the real thing.
A buyer who really wants a MC275 IV will buy a real one, not a clone. Even if this performed 100% like a real 275, that's not good enough for many or most McIntosh buyers, I'd bet. It is simply marketed to a different buyer. The only real competition would be used equipment; I see a MC275 III on eBay for around $4K BIN, which is double the cost of the clone in this post. I don't really see how this hurts McIntosh at all, considering that this is a couple revisions back and not a current model.