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Comparing dual-SID solutions

T

his is an ARM2SID in my sixtyclone:

Before now, I didn't appreciate that the ARM2SID is two ARMSIDs in one package. You might guess that from the name, but most of the pictures show two of them hooked together which gave me the incorrect impression that you needed two. Having two of these connected together actually gives you 3-SID sound and FM Sound Expander capability. 

At first, I fitted a single ARMSID into my sixtyclone. It has a very good sound, is configurable for 6581 / 8580 and supports paddles. 

For dual-SID work, I first tried the SID2SID board. It's cheap and easy to install, doesn't overhang any chips and works fine with two ARMSIDs. The drawback to this is that the second SID sits at either DE00 or DF00 and that's it.
So for more configurability I tried a MIXSID. This gives you loads of configurability (ie option of having second SID at D420) and also allows you to mix the stereo. 
A drawback to this solution is the size of it. I had to use an extra socket to raise the board up. It just about fits into my C64C-style case but it is completely covering the CPU which is probably not ideal. 

Those ARMSIDs are sadly no longer in the land of the living. The MIXSID didn't appear to work at first, but it turned out to be a dead ARMSID, which I was sure worked the last time I used it. I bought a couple of cheaper SwinSID nanos to use until I was sure that the MIXSID was working. Everything has been working fine with those in place, but when I tried the known-working second ARMSID, that one broke too. 

I'm fully prepared to accept that it's something that I've done wrong, and may not even be related to the MIXSID but I don't know what. The MIXSID works fine with the SwinSIDs in place, and I would have continued with that arrangement; the SwinSID sounds better than I expected. The drawback of that is that the SwinSID doesn't give paddle support and I do like paddle games, and I use paddles as controls in my own software. 

As you can see in the top photo, my ARM2SID has arrived, is now fitted and sounds great. It has the footprint of a single SID, it handles paddles and I have the 'second sid' appearing at D420, mirrored at DE00 and also at DF00, so that covers all bases. it's easy to configure using the utility they supply, including some filter settings. I have the stereo output going to a 3.5mm jack fitted to the case. SID one still goes to the audio/video DIN as with a single SID.  I'm really happy with this solution.  




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