Search found 9 matches

by MattM
Mon Jul 04, 2016 2:43 pm
Forum: JLM Audio Kits
Topic: LA500A opto comp leveling amp BUILD THREAD 500/51X
Replies: 211
Views: 458167

Re: LA500A opto comp leveling amp BUILD THREAD 500/51X

Hi Joe -- bumping this question, since I think it got overlooked: I'm curious what the advantage/disadvantage is to having the VU and GR handled on different pots rather than in standard, "balance" mode? Took me quite a while to get the hang of the balance pot. Even if you're not matching for stereo...
by MattM
Wed Jun 15, 2016 3:12 pm
Forum: JLM Audio Kits
Topic: LA500A opto comp leveling amp BUILD THREAD 500/51X
Replies: 211
Views: 458167

Re: LA500A opto comp leveling amp BUILD THREAD 500/51X

Ah, OK, got it. Yes, they're a matched pair. I'm curious what the advantage/disadvantage is to having the VU and GR handled on different pots rather than in standard, "balance" mode? Took me quite a while to get the hang of the balance pot. Even if you're not matching for stereo, is there an advanta...
by MattM
Wed Jun 15, 2016 12:43 pm
Forum: JLM Audio Kits
Topic: LA500A opto comp leveling amp BUILD THREAD 500/51X
Replies: 211
Views: 458167

Re: LA500A opto comp leveling amp BUILD THREAD 500/51X

OK, got it. I have a Radial Workhorse, which has those nice LINK-> switches on the back of the unit. First time I've used them, and they work great. I set both units to show -5db on the VU. I then pulled both link knobs so the blue lights are lit. The meters move _slightly_ off -5db -- one goes 1/2d...
by MattM
Wed Jun 15, 2016 7:40 am
Forum: JLM Audio Kits
Topic: LA500A opto comp leveling amp BUILD THREAD 500/51X
Replies: 211
Views: 458167

Re: LA500A opto comp leveling amp BUILD THREAD 500/51X

Just wanted to confirm how the stereo linking works, because I don't notice any difference in my two units. I have two units seated next to each other in a Radial Powerhouse. Each of them are calibrated correctly -- when I dial up -5 db, I get a consistent reading in GR and VU modes on each device. ...
by MattM
Wed Jun 15, 2016 6:08 am
Forum: JLM Audio Kits
Topic: LA500A opto comp leveling amp BUILD THREAD 500/51X
Replies: 211
Views: 458167

Re: LA500A opto comp leveling amp BUILD THREAD 500/51X

Confirmed! I ran a test lead from +1 on the transformer (which is connected to the pin that's short in the IDC header) to P+ on the PCB. Full tone, full compressor functionality. So in the interest of not having a single wire soldered between the two pieces while the rest of the connections are on a...
by MattM
Tue Jun 14, 2016 1:50 pm
Forum: JLM Audio Kits
Topic: LA500A opto comp leveling amp BUILD THREAD 500/51X
Replies: 211
Views: 458167

Re: LA500A opto comp leveling amp BUILD THREAD 500/51X

OK, unscrewed the transformer from the module so I could get a better look at the pins underneath. They look exactly like you'd expect -- not pushed under, slipped, or anything. It's as if the pin was manufactured to the wrong length, because it has a very clean, square bevel to it that doesn't look...
by MattM
Tue Jun 14, 2016 9:06 am
Forum: JLM Audio Kits
Topic: LA500A opto comp leveling amp BUILD THREAD 500/51X
Replies: 211
Views: 458167

Re: LA500A opto comp leveling amp BUILD THREAD 500/51X

Hi Joe, checked the ribbon cable connections, and... oops. The pin in the upper left corner (as you're looking at the transformer) either snapped off or melted into the plastic when it was assembled. There's no broken pin in the ribbon cable or anything like that. Any way to bypass that, even tempor...
by MattM
Tue Jun 14, 2016 3:57 am
Forum: JLM Audio Kits
Topic: LA500A opto comp leveling amp BUILD THREAD 500/51X
Replies: 211
Views: 458167

Re: LA500A opto comp leveling amp BUILD THREAD 500/51X

Swapped out the JLM99V from my other (working) unit. Same result. Other suggestions?
by MattM
Tue Jun 14, 2016 2:10 am
Forum: JLM Audio Kits
Topic: LA500A opto comp leveling amp BUILD THREAD 500/51X
Replies: 211
Views: 458167

Re: LA500A opto comp leveling amp BUILD THREAD 500/51X

Just finished building my second of two LA500As, and just ordered two more. LOVE these kits. Great layout, very logical assembly process, looking forward to getting a lot of mileage out of them! I went through and calibrated my first unit without any problems. Loaded up the second one expecting the ...