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McIntosh - Hints and Kinks

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MX117.MC7150 said:
...rechromed, but then all the lettering would be gone. Any source for lettering that anyone knows of?...Thanks.
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I've been thinking about that a lot, since Mom managed to Windex all the lettering off the 275 several years before it came into my possession. :rolleyes: Best thing I can come up with is to use dry-transfer letters (available in craft/hobby/officesupply type stores), then spray-lacquer over the lettering (and maybe even over the whole darned chassis). Another possibility would be to see about paying someone to create a new silkscreen for you based on a photo of the amp?

As more pieces get old and start rusting, this is going to become more of an issue for more people. We need to come up with a solution. :)
 
Now what did I do?

Hi Terry,

I just finished recapping my Stereotech 1200. Everything seems fine but I have noticed that the right channel heatsink is much warmer than the left. If I leave the unit on with no input for 1/2 hour and then check the sinks it is noticeable. The voltage across the bias pots is different. I have the service manual but there is no mention of where to measure the bias and what it should be set to.

Any help is much appreciated.
 
mrz80 said:
I've been thinking about that a lot, since Mom managed to Windex all the lettering off the 275 several years before it came into my possession. :rolleyes: Best thing I can come up with is to use dry-transfer letters (available in craft/hobby/officesupply type stores), then spray-lacquer over the lettering (and maybe even over the whole darned chassis). Another possibility would be to see about paying someone to create a new silkscreen for you based on a photo of the amp?

As more pieces get old and start rusting, this is going to become more of an issue for more people. We need to come up with a solution. :)
Click to expand...
Once I'm retired (later this year) I'm thinking of offering this as a service. You send me your striped chassis and I'll have it re-chromed and will apply new lettering.
 
The 1200 manual doesn't give the one critical voltage you need, the voltage across R619 or R617, the .5 ohm output emitter resistors.
Possibly measure the cooler channel and adjust the other to match.
 
Here we go again!

Thanks Terry, I will try a few things. :beer:


Then I'll probably contact you again when I blow it up! :thmbsp:
 
Can anyone help me please, I have just purchased a c2300 without warranty but in pristine /new condition and to say that I was thrilled would be an understatement.

Briefly using Classe. ca400 monoblocks with Meridian G08 and Pink Triangle T/T with battery psu and Whest ps30 phono stage I wanted to be able to compare whest mc against Mcintosh on board mc stage.
I have no idea what I have done wrong but now I cannot get sound from either T/T or CD Player both units are connected via XLR and the Tuner via RCA.

All tubes are working or at least they are lit !

Being in my seventies and not too clever with the technical aspects I woul be most grateful if someone could make any suggestions.

Thanks in advance--Tony
 
It would be much easier to troubleshoot over the phone, you are more than welcome to call me (see the link to our website below) and I will help you figure this out quickly.
 
Hi Ryan----just let you know that for some reason the balanced inputs on the c2300 now work correctly.

I am most grateful for your efforts on my behalf.

Thanks

Tony
 
Does anyone know which optical block (Sony?) is in the MVP861?
Same question on the transport.......which one is in the MVP861?
Thanks.
 
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Improve MC2500.....

If your anything like me, the MC2500 has always just sounded pretty good to me... I have found that a couple of tweaks will make it a very good sounding amplifier.

#1 Replace all electrolytics

#2 On the back where the input board is located, there are a couple cheapo bi-polar electrolytic capacitors used for coupling. Replace these with this capacitor: http://www.mouser.com/ProductDetail...EpiMZZMukHu%2bjC5l7YeioJxFs256s1R8gcs%2bkb8U= and yes, they will fit perfectly after you adjust the leads.

#3 Bypass all of the big filter capacitors with a 1uf - 5uf 250v or so, good quality film cap of your choice.

This did improve the sound of the amp and IMHO is worth doing.
 
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Yesterday I replaced a couple of burned out bulbs on my C2200, plugged it back in and NOTHING. No lights anywhere on the panel, no power either, just wondering what possibly could have gone wrong, and the main fuse is fine (tested).

UPDATE: Took it into the shop and all is well, loose ribbon cable, bulbs all replaced.
 
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Proper assembly of MX130 Glass Panel. Help!

Problem solved
 
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Mc 225 Thermistor replacement?

In another thread I'm rebuilding the power supply of my MC 225, and a question or two has arisen. first, what does everyone use to replace the thermistor with?

Secondly, when replacing the bias diode with a 1n4007, which way is the band oriented? The original has one wire on one side, and two on the other.

What is the value of the bumble bee that is on the small power supply board?

Thanks,

Russellc
 
I would use the G.E. CL-80, 47 ohm, 3 amp, NTC, gives a nice soft start.
The band is the + end, this is the end that goes toward the transformer R46-R47 junction.
The capacitor is a .01uF use 630V, C24.
 
Thanks a lot Terry, much appreciated. I'll get the thermistor ordered. Terry, the schematic shows 2 .01 caps with the high voltage diodes. where are these located on the amp? I dont seem to find them on the small power supply board,
did some not have these 2 caps? Or am I just too stupid to find them?:stupid:

russellc
 
One is on the small board, and the other is between the 2 doubler capacitors on the divider plate.
 

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dewickt said:
One is on the small board, and the other is between the 2 doubler capacitors on the divider plate.
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Holy crap,thanks a lot! I should have traced the circuit out further on the amp.

I'm getting ready to order, found the thermistor, the 22 uf 450 volt cap for the bias, 1N4007 diodes, but was wondering about the other bumble bees, the four on the board ( .047 uf), I have SBE 716 .047 @ 600 volts. I dont want to ruin the sound of this amp is there another you reccomend for this position? Similarly, the two bumble bees on the volume pot I also have SBE 716 .1 @ 600 volts as well, but I just happen to have these, I'd just as soon order different ones, I want this amp done correctly part wise. Your recommendations are appreciated.

Last caps are the 2 small electros on the large board, I believe they are the cathode bypass caps, seems I remember seeing the Sprauge atom 100 uf @ 100 volts recommended for this position, do you think the voltage is high enough? Seems like it ought to be 450 or so?

Thanks alot for the time and advice,:thmbsp:

Russellc
 
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