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<div style="font-family: Calibri,sans-serif; font-size: 11pt;">Good work fella! <br>
<br>
Tim</div>
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<span style="font-family: Calibri,sans-serif; font-size: 11pt; font-weight: bold;">From:
</span><span style="font-family: Calibri,sans-serif; font-size: 11pt;"><a href="mailto:tprivitera@nc.rr.com">tprivitera@nc.rr.com</a></span><br>
<span style="font-family: Calibri,sans-serif; font-size: 11pt; font-weight: bold;">Sent:
</span><span style="font-family: Calibri,sans-serif; font-size: 11pt;">27/02/2016 00:45</span><br>
<span style="font-family: Calibri,sans-serif; font-size: 11pt; font-weight: bold;">To:
</span><span style="font-family: Calibri,sans-serif; font-size: 11pt;"><a href="mailto:analogue@hyperreal.org">analogue@hyperreal.org</a></span><br>
<span style="font-family: Calibri,sans-serif; font-size: 11pt; font-weight: bold;">Cc:
</span><span style="font-family: Calibri,sans-serif; font-size: 11pt;"><a href="mailto:synth-diy@dropmix.xs4all.nl">synth-diy@dropmix.xs4all.nl</a></span><br>
<span style="font-family: Calibri,sans-serif; font-size: 11pt; font-weight: bold;">Subject:
</span><span style="font-family: Calibri,sans-serif; font-size: 11pt;">[AH] FIXED: Arp Solina with excessive chorus noise</span><br>
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<div class="PlainText">Hi Everyone,<br>
<br>
I wanted to follow up with the list on the fix for this. It was indeed a VERY noisy TCA350Y BBD chip and it took a while to get a NOS one shipped to me. I just replaced it last night. About $10 each from either musicpartsguru on eBay or Wutierson in Spain.<br>
<br>
I first replaced the decoupling caps on each of the 3 modulation boards while I was waiting on the chip delivery (I had the 220uf caps handy and figured it wouldn't hurt). The chorus got a little louder, relative to the bypassed sound, which was a good thing,
but the loud, obnoxious swooshing sound remained. The little pots on each of the 3 boards are volume pots for each chorus section. I simply raised and lowered each one until I found the one that affected the volume of the swooshing noise. Beware the pads
and traces on these boards are very delicate, so be careful. Just using my hand-held, spring-loaded solder sucker pulled up a couple of the pads. Everything was pretty easy to work on "in place" as the boards are mounted on a hinged support tray, which is
easy to access from both sides.<br>
<br>
Disengaged, the unit is dead quiet and engaging the button for the chorus yields very little background hiss at all - no more than the chorus on my Juno 60, which is pretty quiet.
<br>
<br>
The Solina truly sounds amazing now and I hope this will help anyone trying to troubleshoot a similar issue.<br>
<br>
BTW, I did end up re-capping the power supply after the BBD chip replacement, just for peace of mind, as everything has '76 date codes. Please no religious wars on the preemptive capping issue (-:<br>
<br>
Tim<br>
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<br>
Hi all,<br>
<br>
I recently picked up a 70's Arp Solina String Ensemble. It has the button on the right cheek block to turn the chorus on/off and it is not the later version with LEDs.<br>
<br>
It's in pretty good condition, every function works and it sounds great, but there is, in my opinion, excessive noise and 'swooshing' when the chorus/modulation circuit is engaged. It is dead silent with the chorus turned off. Not a big deal when you are
playing notes or chords, but enough to be annoying when it's idling.<br>
<br>
I downloaded the service manual/schematics and it looks like there are adjustment pots on the modulation boards. Anyone had one with a similar issue adjust these or can suggest some ideas to reduce the noise? I will be re-capping the power supply later this
week for preventative maintenance, as I do with all my synths, combo organs, etc.<br>
<br>
Thanks in advance,<br>
Tim<br>
<br>
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