Sound Skulptor forums

Build help and troubleshooting => LA502 Optical Compressor => Topic started by: igor.moreno on December 01, 2022, 04:30:02 PM

Title: Hissing LA502
Post by: igor.moreno on December 01, 2022, 04:30:02 PM

Hi !
I've got LA502 I built years ago that I don't often use because of it's hiss, which can be too much depending on the sources.
Is there any way to atenuate the hiss ?

Thanks !

Igor

Title: Re: Hissing LA502
Post by: JPK on December 02, 2022, 03:52:10 PM

What is your PCB revision number?

Title: Re: Hissing LA502
Post by: igor.moreno on December 02, 2022, 06:44:50 PM

It's a REV 1.2.

Title: Re: Hissing LA502
Post by: JPK on December 05, 2022, 09:23:46 AM

Do you know this modification?

Title: Re: Hissing LA502
Post by: igor.moreno on December 05, 2022, 12:25:05 PM

No, I did not know this modification.
I'll try it as soon as I have time.

Thanks !

Igor

Title: Re: Hissing LA502
Post by: igor.moreno on December 16, 2022, 01:51:44 PM

Hi,

One of the knobs screw broke, making the disassembly of the unit impossible...
Do you have any tip to remove the broken screw on the knob without making too much damage ?

Thanks,

Igor

Title: Re: Hissing LA502
Post by: JPK on December 16, 2022, 04:54:48 PM

A 2.5mm drill into the hole. If the thread is damaged, it does not matter because there is another screw on these knobs.

Title: Re: Hissing LA502
Post by: igor.moreno on December 17, 2022, 05:37:10 PM

OK, thanks, i'll try that !

Title: Re: Hissing LA502
Post by: UrbanOsterman on March 12, 2025, 01:23:39 PM

Hi All
I have an LA502 installed into an Bento 10S and it is hissing a lot.
When I go beyond Gain 30 it is a lot of hiss??
When I install it into an Bento 6 I can go up to over Gain 70 before there is a sligth hiss.

Has anybody similar experience?
I have an MP AB528 in series before the LA502
But the MicPre is very silent.

Regards
Urban Osterman

Title: Re: Hissing LA502
Post by: JPK on March 12, 2025, 05:39:51 PM

Some Bento's have a very noisy PSU.
Try moving the LA502 to a slot that is further away from the PSU?