What is value of Electrolytic Cap with legend 15/ on Vintage TAC Mixer

[Brian Roth]

Spoke to an audio engineer I trust and have decided to leave Tants in as it constitutes the sound of the desk. He advised to run signal sweeps to see if old electrolytics causing frequency loss. I have bought replacement Nichicon radial caps just for one channel as a test too, I can always put old caps back in if I don’t like what new caps do

Keep in mind, those old tants can perform distinctly different tasks.

1.  In the direct signal path with actual audio signals passing through.  Very typical in some of the vintage Neve gear, etc.  Those caps can indeed affect the "tone" of the circuit.  They are not particularly stressed and a (seldom) failure impacts only the signal path vs.  causing smoke.

2. As power rail bypass caps.  Those have done the "heavy lifting", usually for decades, as the full PSU rail voltage has been on/off them all these years.  THOSE are the ones I see failing more frequently after the years, and they often fail as a short circuit from a PSU rail to 0V/"ground".  Sometimes smoke results.  Those are the ones I keep my eyes on!

Bri

 

[tomheavybeats]

Keep in mind, those old tants can perform distinctly different tasks.

1.  In the direct signal path with actual audio signals passing through.  Very typical in some of the vintage Neve gear, etc.  Those caps can indeed affect the "tone" of the circuit.  They are not particularly stressed and a (seldom) failure impacts only the signal path vs.  causing smoke.

2. As power rail bypass caps.  Those have done the "heavy lifting", usually for decades, as the full PSU rail voltage has been on/off them all these years.  THOSE are the ones I see failing more frequently after the years, and they often fail as a short circuit from a PSU rail to 0V/"ground".  Sometimes smoke results.  Those are the ones I keep my eyes on!

Bri

Great advice, thanks Bri. There's 4 Tants per channel so will trace PCB and see if any are connecting to power rails

 

[abbey road d enfer]

Spoke to an audio engineer I trust and have decided to leave Tants in as it constitutes the sound of the desk. He advised to run signal sweeps to see if old electrolytics causing frequency loss. I have bought replacement Nichicon radial caps just for one channel as a test too, I can always put old caps back in if I don’t like what new caps do

I really would like you to compare objectively channels with tants with those with new Al and report to the group, maybe comparative audio files. I believe it would be of great value for all members.

 

[tomheavybeats]

I really would like you to compare objectively channels with tants with those with new Al and report to the group, maybe comparative audio files. I believe it would be of great value for all members.

Great idea and will do!