Boss DM2 aliasing issue

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Bigfoot2000
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Joined: Mon Nov 25, 2019 10:16 pm

Boss DM2 aliasing issue

Post by Bigfoot2000 » Thu Aug 06, 2020 2:43 pm

I have a boss DM2 from the 80s in near mint condition, but I’m getting that high pitch sound in the repeats that is apparently called “aliasing” and is apparently due to the clock chip or something. The trim pots haven’t been touched so i don’t think anyone’s messed with it

Reading forums, apparently you can mark with a pen the current settings and adjust it by ear, but apparently this is a no go without an oscilloscope and stuff

Can anyone help? Is there someone that could check it out for me? I had one before and it was the best delay Id heard but I sold it. Now I have this one and it’s got that annoying aliasing sound and doesn’t self oscillate like my previous one.

Any help would be appreciated!
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Dr Tony Balls
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Re: Boss DM2 aliasing issue

Post by Dr Tony Balls » Thu Aug 06, 2020 3:06 pm

You can absolutely adjust a DM2 by ear. I'd mark the current settings either with a pen or just take a pic of them then you can adjust by ear. Set the delay to max, and the blend and feedback to the middle, and adjust the "clock" trimmer (should be VR3) by ear to get the maximum delay time before you hear any whining.
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Bigfoot2000
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Re: Boss DM2 aliasing issue

Post by Bigfoot2000 » Thu Aug 06, 2020 3:35 pm

Thanks man, I will try this over the weekend. As the pedal struggles to self oscillate and blend will be about 50%, I assume this will make it easier to get rid of that annoying whining sound.
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Bigfoot2000
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Re: Boss DM2 aliasing issue

Post by Bigfoot2000 » Wed Aug 19, 2020 7:04 pm

Dr Tony Balls wrote:
Thu Aug 06, 2020 3:06 pm
You can absolutely adjust a DM2 by ear. I'd mark the current settings either with a pen or just take a pic of them then you can adjust by ear. Set the delay to max, and the blend and feedback to the middle, and adjust the "clock" trimmer (should be VR3) by ear to get the maximum delay time before you hear any whining.
I had a go at this earlier. Seemed ok while the pedal was opened up and managed to dial out the aliasing, but when I closed the pedal back up the delay time knob literally did nothing, just stayed at the setting I adjusted to. Man, I need to check it out again when I get more time. Working from home because of a pandemic and living with the Mrs and a 6 year old means personal time is scarce at the moment. Got any ideas?
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1976@metal
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Re: Boss DM2 aliasing issue

Post by 1976@metal » Wed Aug 26, 2020 7:13 am

Bigfoot2000 wrote:
Wed Aug 19, 2020 7:04 pm
Dr Tony Balls wrote:
Thu Aug 06, 2020 3:06 pm
You can absolutely adjust a DM2 by ear. I'd mark the current settings either with a pen or just take a pic of them then you can adjust by ear. Set the delay to max, and the blend and feedback to the middle, and adjust the "clock" trimmer (should be VR3) by ear to get the maximum delay time before you hear any whining.
I had a go at this earlier. Seemed ok while the pedal was opened up and managed to dial out the aliasing, but when I closed the pedal back up the delay time knob literally did nothing, just stayed at the setting I adjusted to. Man, I need to check it out again when I get more time. Working from home because of a pandemic and living with the Mrs and a 6 year old means personal time is scarce at the moment. Got any ideas?
I hear that mate ! :shocked:
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