• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

McIntosh - Hints and Kinks

Status
Not open for further replies.
MR 77 Multipath light

I have just finished putting a new faceplate and bulbs in the tuner and she looks and sounds wonderful.....I have noticed the multipath light cut out at times though....I have turned all knobs and nothing happened accept when I turned the mono-auto-stereo knob to the far left, then it came off and on, could this be a simple deoxit or is it in need of some "Terry TLC"???
 
Terry good day,
I dont know what to do with MC352 problem, i tried all option that you recomended with no luck, the same problem remained, i changed -/+ on speakers it did not influenced on a sound.
I look forward for your advice, what more can be done?
please help me.
thank you
Lev
 
Dead channel on MC250

What would be the logical place to look if the following symptoms occur. One channel begins to get loud static and popping sounds followed by a loud snap/pop. The channel then goes dead. It is not completely dead but you have to turn the volume all the way up to hear faint music. I have replaced every internal electrolytic capacitor as well as all four output transistors. I have a DVM but no scope or signal generator. I do not see any resistors that obviously look burnt or open. Any suggestions? I'm tempted to try swapping internal signal cables to at least see if the problem is in the first preamp section or the driver/output section. Thanks.
 
please forgive me if this has been addressed already but i am having problems with my stuff. i recently bought a great pair of speakers and am hearing my gear essentially for the first time so naturally it has to start acting up. i have an mc275, c22, and mr71 (mi-3 too, but it isn't hooked up). i have long wrestled with reception issues, but that is not my biggest problem. lately there has been a hum that i cannot seem to isolate. i am not at all adept at this, but usually i can figure out if it is the amp or the preamp by flicking switches around on the pre to see if anything illicits a change and if it does i assume it's the pre (of course i could be dead wrong about that). in this case nothing seems to change it which indicates the amp, but again i am not sure about this. so what happens is once i turn everything on the humm slowly starts to build as it warms up maybe even gradually getting worse over a long period and then, every so often, there is a loud pop and the hum disappears completely and everything sounds perfect for a variable period of time and then the hum comes back. there is also a similar loud pop when i shut the power down at the pre if the hum is present although shutting down and powering back up does not fix the problem for any length of time the way the random pop does.
can anybody help me with this? i sure as hell don't want to haul that thing back to the shop. thanks,
 
I've searched through the forum for anyone noting humidity issues. I've got a MHT200 that's shutting itself completely off and then returning to standby at random intervals. Once it starts, it won't stay on. As soon as I take it out of standby, it will shut off and return to standby a few seconds later. I believe it's somehow related to the relative humidity in my house as it only occurs during periods of greater than 60% relative humidity. A couple of times I've noticed the glass appeared "foggy" from the inside of the blue LED readout. I'm wondering if this is some sort of safety function or if I need to have a professional service done on the unit. Has anyone else has seen something like this. I know there are a ton of folks from Florida on the boards so maybe this has happened to them as well.
 
Greetings,

I'm about to start the restoration of a pair of MC-50's and a MC-250. Just a few quick questions concerning repairs. Are there any current semiconductor replacements(faster,more stable transistor/diode replacements) that should be upgraded?

How about cross ref's for:

145A136 red dot

F 021 718 yellow dot

Any ideas in play on extending the HF signature slightly(cap bypass, film coupling, blocking etc)?

Thanks,
Samuel
 
I use Nichicon Muse KZ and ES for the preamp and driver sections, not sure about replacement parts except the outputs are MJ15003. I normally use the recommended part for diodes, buy them from the factory, I can cross reference most from a model and schematic reference number from the service literature, the numbers on the actual part are mostly date codes and variations of the house part number that is assigned by McIntosh. The house number is listed in the service literature and is the starting point for me. Watch out for the sand block 5 watt resistors, the type used by McIntosh are also used a fuses, they are designed to open when hit with an over current condition, this is a safety feature designed into the part.
 
Mc-50/250

Hey Terry,

Any sources where I can purchase the correct replacement 5w sand emitter resistors? Are they a special design?

Thanks,
Samuel
 
MC 2100 hisses in the right channel

Ok, it is an MC 2100 that I have been helped with by Terry already as to cap replacement. Thanks Terry, the Nichikon caps worked out great.

I am ready to begin looking for the source of a right channel hiss.

So to understand, I need to disconnect my RCA preamp inputs and see if the hiss goes up and down with the gain controls to isolate C 32preamp/other inputs from amp issues? I just read the C 32 ribbon cable post a bit ago.

With everything connected I already note the hiss does goes up and down with the right gain control. It's just enough "there" to note at no preamp volume, and warn me it is time to find the issue.

I think tomorrow I will disconnect the turntable, tuner, and CD from the preamp and see if it is an input.

If I am directed to disconnect the preamp from the amp, I think I will connect the garage speakers rather than the Cornwalls for that test.

Presuming I am only concerning myself with the amp, after a no preamp no input gain knob turn and listen gets me the hiss, where to start?

The amp runs cool. I never did put the screws back in for the cage after the cap replacement. I have slid the amp out, removed the cage, and placed my hand on the sinks after 30 -45 minutes of play time. The sinks are quite comfortable to the touch.

The amp hisses more noticeably at start up than after playing a while, I think (maybe).
There was no hiss after the cap replacement, this hiss just sort of "came on" a bit later.

So:

Should I disconnect power and begin checking across resistors with my ohm meter for rated resistance versus actual?

Is the "freeze" spray I have heard about valid? Play, spray, ( pray :yikes: )and listen for increase in noise? Didn't see one suggestion to freeze spray in this entire thread, so the lack of that suggestion makes me suspicious.

Well, I wanted to jump in so I will get notification of replies, and begin this. I am on vacation for the next ten days, so I wanted to get this done, among other things.
Thanks Jeff R

Ah yes, and if I do find out of tolerance resistors, source from the McIntosh factory, or from whom should ? purchase new resistors?
 
I am sure this is not a McIntosh problem; but perhaps someone can give me some good advice. I have a pair of new McIntosh 1.2KWs. They work great. Don't laugh but for now, I have them hooked up into the Preamp Ins of a very old Sansui QR 6500 Quadraphonic Reciever. I have them hooked into the front two channels of this reciever. When I play my Cd player or IPOD Classic through this system; the sound is fine. If I hook in my laptop listening to an internet radio program such as those on Live Radio 365 or Hearts of Space; I get a very low hum/static sound through my speakers. Can anyone tell me what this is about and what I can do to remedy this? Thanks Scottsmrnyc
 
I would wonder about the volume setting on the laptop headphone output, if that is what you are using. I bought a set of those Bose powered laptop speakers. The Bose manual states to be 60% or lower on the headset volume setting.
I blew the first set of Bose up forgetting and having it too high. Or at least they went dead. The second set has no had an issue since I keep the laptop volume below 50%.
When I have hooked the laptop up to my C 32, I can't recall hearing any noise. When I connected it to my KA 7100, I think had to turn the laptop volume down or I heard noise, best I recall.
My best guesses. Lower the laptop volume. I presume you are running a mini RCA split to two RCA jacks in all this reply.
jeff
 
Yes, sorry for the delay in responding. I am running a splitter. I will try your suggestions. I have put the laptop volume to the max. Maybe I will lower it to half and then increase the volume on the Sansui QR 6500 which I use as a pre amp. By the way, of course I am thinking about getting a new McIntosh pre amp. Perhaps the2300. Do you think a new Mcintosh preamp will make a substantial difference in the sound? Thanks Scottsmrnyc
 
Scott,
I am not at all qualified to advise on which Mac preamp to buy. I would email Mr DeWick about that, or other members.
Did lowering the volume output help the noise?
Jeff
 
McIntosh 2205 Question

Greetings:

My 2205 just arrived from ebay! It is a heavy behemoth, hooked up and sounds wonderful and looks even better. I noticed the only lights on the front are the meters, WATT/DECIBEL and the L & R green lights. The McIntosh logo and all lights I presume on the bottom row are not lit. Am I corrrect in assuming those DO light up?
 
Has 4 each #1866 (sub #1847 or #47), they are in line with the controls. You have 2 options to replace them, pull the panel and do it from the front or I think the easy way by pulling the bottom and popping the holders out with a squeeze and replace them.
 
Status
Not open for further replies.
Back
Top Bottom