Novation Bass Station Nightmare

[WellingtonCrab]

When I got this synth it work great except for two pots that were crapped up and causing a strange sort of rapid tremolo effect, which would disappear with a bit of gentle pressure exerted on the crappy controls and then it operated beautifully.

This lead to a month or so of playing it with taped up controls and tweaking parameters with midi which I made the poor judgement of being too much of a pain in a*s.

So I took it to the local "audio video repair" place, or rather the the only place that would touch it, which consisted of a private residence packed to the brim with gutted electronics, and after a futile many month long attempt to find replacements parts the guy stuck in some third party controllers in it and gave it back to me.

To my horror this effect now seems to be permanent. I am using a 9v/800ma radioshack power supply and have tried many others with no real difference. I can kind of mitigate the effect with inconsistent results by playing with the envelope settings, and sometimes magically I'll plug it in and it will function perfectly (provided none of the controls are touched) for a period of up to 10 seconds, but no matter what the distortion will reappear, and any adjustment to the controls will cause it.

I wish I could describe the sound better, as it is different every time, but I am attaching a sound clip.



or "http://www.mediafire.com/?vj9e94tbfmy"

I guess I don't really expect anyone to be able to diagnose the problem from just my poor description and an mp3, but I guess I really just need guidance on where to go from here. I don't want to go to the same guy, and I don't even know if it's a problem that's worth the ultimate cost of getting fixed.

I guess what would you do? Sell it for parts? Send it off for repairs and $60 dollar bench fees? Get a degree in circuit board engineering?

-Matt

[killedaway]

dang, that sucks!

wish i had some advice, but i'm not extremely technically-minded (see my own posts in "Help!"). it certainly sounds like the problem is stemming from those pots. when you say the guy "stuck in some third party controllers", do you mean that he replaced the pots entirely, directly on the board? did he say it was fixed when he gave it back? hopefully you didn't pay him...?

also, if you can't make heads or tails of it, and decide to let it go, shoot/PM me a price; i'd love to see if i could ruin it further! (not serious about ruining it, but serious about buying it from ya).

good luck!

[WellingtonCrab]

Yeah they are entirely new pots, his prognosis when I brought it in was that he pots would have to be replaced.

I made some pretty bad choices, one being that he wanted as little of the machine as possible, so I only left him with he front half with the controller circuit board. So I payed him, brought it home, stuck the two together and wa-la: s**t.

If I don't make any near term progress with it I will send you a pm, it's a shame as I really thought it sounded great and was easy to use.

-Matt

[oli]

Hi,

Which pots are they? Maybe I can help. From your initial description, it just seemed like dirty/dusty pots. A replacement should have fixed that. Have you got specific information about what was removed, and what new parts were fitted? Have you still got the old parts?

[madtheory]

Sounds like a poor repair job. The fault may not be with the pots at all, and your "tech" was unable to diagnose properly.

Take it to someone who can fix synths! Even if you have to post it. That wouldn't be expensive with a synth of that size.

[oli]

I think the question is whether it is worth putting much money into a cheapish synth. I'm not meaning to be disparaging here, as I have one too.

[WellingtonCrab]

Hi,

Which pots are they? Maybe I can help. From your initial description, it just seemed like dirty/dusty pots. A replacement should have fixed that. Have you got specific information about what was removed, and what new parts were fitted? Have you still got the old parts?

Hey Oli thanks for the reply!

I had the filter resonance and envelope sustain controls swapped out. I have one of the old controls but the other he said was damaged (beyond already being in poor condition) when it was removed.

I also have two extra pots of the new ones he put in it. The are noticeably larger than the original controls and read "50KD 0425" and the original are "B50K" (which I think indicates they are both 50k pots?).

Looking at the soldering job on the back the solder points them selves look neatly done, but around them there is some noticeable black/burnt and semi translucent residue (flux?).

Should I maybe try just completely removing the replaced controls with a de-soldering iron?

Thanks so much for any help or advice you can offer me.

-Matt

[madtheory]

The black is OK. I'm guessing the replacement pots are too noisy for the scanning system. I would go look for better quality pots...

[WellingtonCrab]

Anyone have any leads or specs for good replacement pots for the bass station?

-Matt

[Yekuku]

Hi Matt,
U can order replacement pots directly from novation, they are available.
The issue is that the available pots are a bit longer than the old ones , so expect them to stick out.
I can provide a pic of the original replacement pot if u need.
The specs on the pot read : 850k , alpha
Hope this helps.

[WellingtonCrab]

Hi Matt,
U can order replacement pots directly from novation, they are available.
The issue is that the available pots are a bit longer than the old ones , so expect them to stick out.
I can provide a pic of the original replacement pot if u need.
The specs on the pot read : 850k , alpha
Hope this helps.

Thanks for the reply Yekuku!

I had no luck before in trying to get parts from novation (the guy was very eager to help, but he would always just send me to these small repair place's websites which wouldn't return my calls or wouldn't actually carry any parts for the product), but it sounds like it might be worth another shot.

-Matt

[oli]

Hi, you probably know already, but the 'B' would usually indicate linear taper potentiometers. I think yours are 50k Ohm linear types. Not sure why the replacements haven't worked. I would be a little concerned that it may not be an issue with the pots. You could try shorting out the pots, and see if the problem still occurs. You would have to be careful not to short +5V to ground though.