Technics SU-V9/909 owners.......

[Cogsinister]

As many of you may be aware i own a rather rare Technics amp the SU-V909....it is the computer drive version of the SU-v9 and internally it looks very much the same.

I love this amp, it sounds awesome......it drives my JBL L110's to perfection....

One problem i have with it tho...and i wondered if this was a problem with similar Technics amps is that the input selector switch is remotely located at the back of the amp....it is right at the top of the case very near the top case holes.....and it gets clogged up with dust.

The other Two switches on the board ( recording selector and phono selector/sensitivity ) are not effected...they are much lower down out of the dust....this room is rather dusty btw...

Sometimes its a few of months between the sound going downhill ( right ch low and scratchy) some times just a few weeks.

A good flush out with contact cleaner and then a liberal treatment with DeOxit cures the problem and restores the sound to normal.

I am thinking of covering the switch up to stop dust ingress.....any ideas on how i could do this......i dont want to impede airflow ...as you can see the amp is very packed and gets rather warm.

Thanks.

The switch in question........

 

[Cogsinister]

I have done this for now.....a bit of stiff card over the top of the switch......lets see if this stops the problem........

 

[Montycat]

Just a thought, but have you considered a blower fan to keep dust away?

I've never done this but why not a small computer fan hooked up near the switch blowing away from the amp. I can see it's pretty tight in there and I don't mean to put it inside necessarily but the dust must get in through vent holes in the vicinity. You might just have enough room though to the left of it and it would send air or draw out the top pushing away those little bunnies.

And maybe, just maybe, you could find a source of DC (5V? maybe 12volts?) inside to run it. If it does work it could have a potential side benefit of a bit of extra cooling.

 

[Cogsinister]

Just a thought, but have you considered a blower fan to keep dust away?

I've never done this but why not a small computer fan hooked up near the switch blowing away from the amp. I can see it's pretty tight in there and I don't mean to put it inside necessarily but the dust must get in through vent holes in the vicinity. You might just have enough room though to the left of it and it would send air or draw out the top pushing away those little bunnies.

And maybe, just maybe, you could find a source of DC (5V? maybe 12volts?) inside to run it. If it does work it could have a potential side benefit of a bit of extra cooling.

I had considered that....but i was going to put it near the transformer.....which is the hottest bit of the amp...never considered it to keep dust away from the switch......i do have a small CPU fan connected to a 12v supply that i used in another amp to keep it cool......just have to find it......

 

[Phototone]

You can get a 120v small pancake blower fan, possibly still at Radio Shack. You can put a household plug on it and plug it into the switched outlet on the back of the amp and it will come on when the amp is turned on. No need to go rummaging around inside looking for proper supply voltage. If you set it on top, I would have it blowing up, drawing hot air (and dust) away from the inside, as hot air rises anyway, best to not go against physics. Cool air will be drawn into the amp thru the vent holes on the bottom of the amp.

 

[MyComa13]

I have an SU-V9 and I'm having a hard time figuring out which switch you're referring to. (I don't see any pics on your post btw.) The input selector on my SU-V9 is one of the large, flat "knobs" on the front.

 

[Hifirob2]

Man, I love seeing pics of that amp!

I would think the card covering it should do the trick, but I'm a sucker for experimenting with little DC fans.

If you do go the fan route, you wouldn't need more than 3 or 4.5 volts to keep the 12 volt DC fan working, yet almost silent. Just be careful of placement - I've encountered some noise getting into the audio circuits (especially noticeable through headphones).

 

[terra1]

I have an SU-V9. The seller said it had dirty controls and required jiggling to maintain sound.

I cleaned all controls and switches and it has been problem free. The selector knob is in front for me.

Like MyCom13 I have no idea what is the switch in question, but I assume it's that long white plastic with metal blocks? Or is it the bank of connections with the RCA cableson the rear panel? If the area does not get hot or require air flow to operate, maybe black electrical tape to keep dust from getting in. Again, I have no idea what the switch is you are talking about.

Not sure I would use cardboard unless I knew it was not going to dry out and catch fire or fall into the circuit board. If the protective shield doesn't work, maybe a cabinet or shelf with glass door, overhang, or curtain.

 

[Cogsinister]

I have an SU-V9 and I'm having a hard time figuring out which switch you're referring to. (I don't see any pics on your post btw.) The input selector on my SU-V9 is one of the large, flat "knobs" on the front.

The large switch on the front of the amp remotely controls the actual switch that is located at the far Right corner of the amp very near the inputs....shortest signal path.....clever stuff..

 

[MyComa13]

The large switch on the front of the amp remotely controls the actual switch that is located at the far Right corner of the amp very near the inputs....shortest signal path.....clever stuff..

Sorry, I couldn't see the pics due filters at work. See 'em now though and understand what you're talking about. Hmmmm....That's a tough one. I'm pretty sure most of the heat is generated on the other side of the amp so I bet you're solution with stock card is good if you don't want to go the fan route. Maybe you could shoot some compressed air through the hood every now and then...just a thought.

Off-topic...looks like you have Technics table next to your amp. What model? I'm running an sl-1200 through mine and love the combo.

 

[Cogsinister]

Sorry, I couldn't see the pics due filters at work. See 'em now though and understand what you're talking about. Hmmmm....That's a tough one. I'm pretty sure most of the heat is generated on the other side of the amp so I bet you're solution with stock card is good if you don't want to go the fan route. Maybe you could shoot some compressed air through the hood every now and then...just a thought.

Off-topic...looks like you have Technics table next to your amp. What model? I'm running an sl-1200 through mine and love the combo.

Yeah, i am hoping the card will work.....time will tell on that one....

The Turntable is indeed a Technics..an SL-1700 Mark 1.

And like yours......sounds superb thru my "909"

 

[Synchro-bias]

I love the wiring for the phono section, very nice looking amp, inside the V9/V909, yours is very clean inside.

 

[Cogsinister]

I love the wiring for the phono section, very nice looking amp, inside the V9/V909, yours is very clean inside.

My 909 is with fellow local AK member Madtech, he had some big speakers to drive and i did not need it anymore, so we did a deal.

I thought the phono section of the 909 was very very good, but i had a lot of problems with the controls getting dirty and needing to be cleaned a lot.

 

[Synchro-bias]

My 909 is with fellow local AK member Madtech, he had some big speakers to drive and i did not need it anymore, so we did a deal.

I thought the phono section of the 909 was very very good, but i had a lot of problems with the controls getting dirty and needing to be cleaned a lot.

Lucky Madtech. I did wonder about those controls, and how there could be problmes, home is prety dusty as room is carpeted - I have no problems with the V8X controls. It phono is pretty good, i use a high output cart 5mv, it clear though. The V9/ 909 look a really nice phonostage. The V9 iam watching is already 245$ atm on ebay... but so tempting