davidaparry
New member
howdy! i recently acquired a bit of an oddball compressor. it has similar tubes to the Gates STA. i cant find much about it on the internet other than a manual / schematic. the person i bought it off didnt know much about it - he said he got it from a well known recording artist who said it was modded but thats all he knows.
anyways, my dilemma is that its kind of working but misbehaves a lot and has some pretty unusable grit in its current state. there is a meter zero and meter sensitivity pot. the meter zero does what it should and the meter sensitivity seems to be a threshold and maybe attack and release all in one. the two scenarios that this pot gives me is:
1. meter shows compression, anytime it compresses it also adds some ugly distortion to the signal. the signal that i hear that isn't the grit sounds nice with some good sounding compression, albeit with pretty fast attack and release. maybe too fast. it also has occasionally thumps of way too much GR. its just super sensitive and random feeling.
2. turning the pot all the way CCW seems to lower the threshold, and slow the attack and release down. now there's more compression showing on the meter and it cleans the signal up with much less grit if any. the problem here is that now there are loud audible thumps with sudden excessive gain reduction that happen unpredictably but correlated to the audio signal. also the meter is completely unreliable here. if i kill the input signal the meter just oscillates on its own.
with both scenarios, the gain staging (input) has little impact if any on the tone. the input and output knobs work as they should and it would be a fine tube preamp if the compression circuit doesn't engage.
i do think it has the potential to sound quite nice and would love to hear anyones insights in to what to focus on! i will be around a retro STA next week and can swap the tubes around and see if that helps.
manual / schematic: https://steampoweredradio.com/pdf/harkins radio/auto level.pdf
anyways, my dilemma is that its kind of working but misbehaves a lot and has some pretty unusable grit in its current state. there is a meter zero and meter sensitivity pot. the meter zero does what it should and the meter sensitivity seems to be a threshold and maybe attack and release all in one. the two scenarios that this pot gives me is:
1. meter shows compression, anytime it compresses it also adds some ugly distortion to the signal. the signal that i hear that isn't the grit sounds nice with some good sounding compression, albeit with pretty fast attack and release. maybe too fast. it also has occasionally thumps of way too much GR. its just super sensitive and random feeling.
2. turning the pot all the way CCW seems to lower the threshold, and slow the attack and release down. now there's more compression showing on the meter and it cleans the signal up with much less grit if any. the problem here is that now there are loud audible thumps with sudden excessive gain reduction that happen unpredictably but correlated to the audio signal. also the meter is completely unreliable here. if i kill the input signal the meter just oscillates on its own.
with both scenarios, the gain staging (input) has little impact if any on the tone. the input and output knobs work as they should and it would be a fine tube preamp if the compression circuit doesn't engage.
i do think it has the potential to sound quite nice and would love to hear anyones insights in to what to focus on! i will be around a retro STA next week and can swap the tubes around and see if that helps.
manual / schematic: https://steampoweredradio.com/pdf/harkins radio/auto level.pdf
