I was fascinated by the X-911 as a kid.. nice to hear it again.. PRO TIP: you could have plugged *any* synth into the 'guitar input' jack and used that to verify the pitch/voltage and trigger circuits..!
You are absolutely correct, and I did do that, just not in the video. The guitar interface (audio to CV and trigger) and the oscillator/voicing (CV & trigger to audio) are two separate stages. For troubleshooting and repair of things in the CV to frequency stage (as I was working on in this video) it's helpful to remove any variables the guitar interface may introduce and control it with CV/gate directly. This was one of 5 units I just repaired/refurbed. All of them got tested and calibrated being controlled through CV/trig on the back AND the guitar interface/audio input on the front. This video was about the repair of a specific problem, not a comprehensive servicing video of this synthesizer.
Very interesting. Still trying to get my head around the problem though. I understand the strong peak signal in the faulty components masks the oscillator signal and since it has a constant frequency it comes across as a stuck pitch. Why is the output however “corrected” giving the mixed signal a normal amplitude / volume? Something down the line must thus normalize that high signal. It’s probably something relatively basic for you but I’d appreciate a short explanation. 😁
There’s one trick I’m wondering if it would sound good on this, I wonder what a basic cv signal recorded to a tapeloop would sound like being ran through this
Man, love how you go in depth on your videos. I hope you realize how appreciated your videos are!!
I second that!
I just started revitalizing old synths - couldn't do it without videos as brilliant as yours...thank you so much!
2:45 - It's easy to fix that "trumpet" preset: just rename it "duck" and you're good to go :-D
I was fascinated by the X-911 as a kid.. nice to hear it again.. PRO TIP: you could have plugged *any* synth into the 'guitar input' jack and used that to verify the pitch/voltage and trigger circuits..!
You are absolutely correct, and I did do that, just not in the video. The guitar interface (audio to CV and trigger) and the oscillator/voicing (CV & trigger to audio) are two separate stages. For troubleshooting and repair of things in the CV to frequency stage (as I was working on in this video) it's helpful to remove any variables the guitar interface may introduce and control it with CV/gate directly. This was one of 5 units I just repaired/refurbed. All of them got tested and calibrated being controlled through CV/trig on the back AND the guitar interface/audio input on the front. This video was about the repair of a specific problem, not a comprehensive servicing video of this synthesizer.
@@Synthchaser certainly, great to see it, regardless.. thanks for your documentation!
Big thumbs up. My favorite videos are yours!
Very cool!
Very interesting. Still trying to get my head around the problem though. I understand the strong peak signal in the faulty components masks the oscillator signal and since it has a constant frequency it comes across as a stuck pitch. Why is the output however “corrected” giving the mixed signal a normal amplitude / volume? Something down the line must thus normalize that high signal. It’s probably something relatively basic for you but I’d appreciate a short explanation. 😁
There’s one trick I’m wondering if it would sound good on this, I wonder what a basic cv signal recorded to a tapeloop would sound like being ran through this
warbly
Oh, this synth has a "kazoo" preset.
yeah either a kazoo or the sound baby alligators make.