Got an M4 C4

luckyed

Addicted Member

• Jan 19, 2013

• #1

I picked up an M4 and a C4 set last week and am enjoying them. They have a few burnt out lights but after some DeOxit are working fine. That preamp is great and really boosts the turntable signal. There seems to be a greater tonal range, more highs and stronger bass than other equipment I've used. Very nice pieces. Now I am inspired to get the Yamaha turntable repaired to help complete the line up.

 

avionic

" Black Knights "------- F-15 " Wizard "

Subscriber

• Jan 19, 2013

• #2

No secrets there.They are a fine combination..:thmbsp:

 

DEAFASABAT

Well-Known Member

• Jan 24, 2013

• #3

You gotta love that gear!

I got my pristine M4 a few years back for $100 and never looked back. Looking for a suitable preamp but the Yamahas seem to be pricey. One day soon...

 

mech986

AK Subscriber

Subscriber

• Jan 24, 2013

• #4

Very nice pairing, of course the obigatory

:worthless

 

luckyed

Addicted Member

• Jan 24, 2013

• #5

This was a good deal too. I got it from a guy who said it had been stored for about 6 years. I did the deoxit treatment but a channel will still occasionally drop out. Now I have a weak signal on one channel of the phono section. I'm going to give it another deoxit treatment. Is there something else I need to look for that could be causing these symptoms? THere is also a slight hum from the amp when the power is on. I'll get some photos up when I pull it out again to clean it.

 

stoutblock

"If it sounds good, it is good." Duke Ellington

Subscriber

• Jan 24, 2013

• #6

To start, set the bias and offset on the amp. Make sure your RCA connections are good. Then listen to whatever Avionic tells you and take notes...

 

brutal

YamaHoarder

Subscriber

• Jan 24, 2013

• #7

And since they have a non-polarized plug, try rolling it over as well. Also try it straight into a good outlet if you're using a strip or multi-outler adapter or some crap like that.

 

avionic

" Black Knights "------- F-15 " Wizard "

Subscriber

• Jan 25, 2013

• #8

Now I have a weak signal on one channel of the phono section

Click to expand...

Deoxit the phono select switch and the input select switch. If the deoxit doesn't work, look at solder connections for the switches.I have had a couple where the switches required removal and repair of contacts and rivets.

 

luckyed

Addicted Member

• Feb 2, 2013

• #9

What size hex wrench is needed for the phono switch on the C4, mine is loose.
Thanks.
I'll get photos tomorrow.

 

avionic

" Black Knights "------- F-15 " Wizard "

Subscriber

• Feb 2, 2013

• #10

1.5mm for the knob.

 

luckyed

Addicted Member

• Feb 3, 2013

• #11

I took the preamp out to clean the switches again and took a photo. Not a great photo. Now to test and see if it works. Last night before I cleaned the switches I played some music. Radio, CD, vinyl. All worked but after about an hour one channel got week again. Very weak. Hopefully the cleaning solved the issue. I'll find out soon enough.

 

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luckyed

Addicted Member

• Feb 3, 2013

• #12

Same issue. Plays well for an hour or so and then I notice that the left channel is softer and visibly shows on the output lights. If I put it in mono I can turn the balance knob left to between the "3 and 4" position and that evens the output lights. Any suggestions? Clean it again? I'll check the RCA connections again. Would a bad RCA jack connection work for an hour or so and then not?
Also, When I turn the amp on I notice a low hum coming from it, maybe the right side. Not through the speakers but from the amp. Is this typical?
Thanks.

 

luckyed

Addicted Member

• Feb 3, 2013

• #13

OK. I answered my own question. I checked the RCA cable to the amp, took them off and back on making sure they were snug. Both channels seem fine now. Great. I really like these two pieces. They even made my cheap, crappy test speakers sound good.