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Technics SU-8044 noisy pots


I'm new here and the proud owner of a Technics SU-8044 Stereo Integrated DC Amplifier that I bought new in 1979. It has served me well through 30+ years of vinyl, cassette, CD and now drives monitor speakers a small basement recording studio.

The only problem is that the volume and balance pots are are now extremely noisy when they're adjusted (fine if not moved). I've tried everything to clean them and got some improvement, but they're still too noisy. I suspect they're just worn out after 3 decades of frequent use.

The volume control is a two-gang pot marked "M 250K Bx2" - which I'm guessing is a dual 250 KOhm audio taper.

The balance control is marked "8N3A 200KW" - don't know what this might be - it has a centre detent.

I've downloaded the schematic and I'll take a look at it but, in the meantime, does anyone have any experience with this amp or know where I can get replacement parts?

It's a very well built unit and replacing the controls shouldn't be difficult if I can find the parts.


Mike Andrew

Technics SU-8044 noisy pots

Try using Caig Labs DeoxIT D5, Then - Caig Labs Fader Lube, Easier than
replacement, besides you need this stuff for your other crusty connections & controls.
A source might be Tayda sells Alpha made dual pots at $.80 ea USD

"two-gang pot marked "M 250K Bx2" " B=linear

A little Tougher:
The balance control is marked "8N3A 200KW" - don't know what this might be - it has a centre detent. A=Log
Could try W/ no detent

Technics SU-8044 noisy pots

Thanks 6Wires - the the Craig Labs stuff is on order (no chance of buying it locally).

If that doesn't do it I'll pull the pots and measure them. I'm hoping maybe the balance control is what's now called "MN" taper - if so they're easy to find now.

The real trick, if I have to replace the pots, will be to find the correct values with the right type and size of shaft to fit the knobs.

Fortunately I also have an old Teac AG-400 - not as good an amp but will do 'til I get the Technics sorted.


Technics SU-8044 noisy pots

I agree to try and clean with the Caig products, as I have found them excellent as well. But after cleaning, you find that they are still very noisy, I would check for DC voltage on the connections to these pots. Pots even when they are old usually don't wear out, they just need cleaning. If after cleaning, they are still very noisy, I would suspect leaky caps in your control amp/tone amp or preamp circuits. DC on the volume or balance pot will appear just as if they are "dirty" when they are turned.
If you clean them again and they are still very noisy, check for DC on the pots and then see if DC is leaking through the below caps:
C117, C118 they are .47uf non polarized caps
C203, C204 they are 1uf caps
C211, C212 they are 3.3uf caps
C213, C214 they are 10uf non polarized caps.

Hope this helps

Technics SU-8044 noisy pots

Thanks tbrander, I've never heard of that before - but it fits the symptoms better than "worn out" does. And getting replacement caps will be much easier than tracking down the right pots. I'll check for DC as soon as I get a chance.