Search found 2067 matches

by Joe Malone
Mon Feb 05, 2024 9:46 am
Forum: JLM Audio Kits
Topic: LA500A opto comp MAY 2021 BUILD THREAD 500/51X
Replies: 108
Views: 184338

Re: LA500A opto comp MAY 2021 BUILD THREAD 500/51X

Okay so terribly slow with this over new year but I sourced some pot cleaner and the problem has remained unfortunately! OK as I mentioned up the page. Can you get the pot of the pot PCB ok without damaging it? Otherwise you will need another pot kit. Ok managed to get make-up gain pot off the PCB ...
by Joe Malone
Mon Feb 05, 2024 9:23 am
Forum: JLM Audio Kits
Topic: MAC Rack kit Build Thread from October 2023 with slow attack led
Replies: 39
Views: 25928

Re: MAC Rack kit Build Thread from October 2023 with slow attack led

If the voltages don't match turn off the comp and leave off for a while and measure the outside pins of the threshold and makeup pots still fully CCW. (Like left threshold 95.76k and right threshold 102.54k and left makeup 9.33k and right makeup 11.11k. be as accurate as you meter shows) Which ones...
by Joe Malone
Sun Feb 04, 2024 5:57 pm
Forum: JLM Audio Kits
Topic: MAC Rack kit Build Thread from October 2023 with slow attack led
Replies: 39
Views: 25928

Re: MAC Rack kit Build Thread from October 2023 with slow attack led

Does anyone know how I can get the two channels a little bit closer in measurements. It seems that I have to throw a lot more signal at channel B than A by looking at the Volts AC. VAC. Almost .5 DB extra on the fader coming out of my DAW to get 1.23 VAC on the B Channel. Is it the output pots that...
by Joe Malone
Tue Jan 30, 2024 12:01 pm
Forum: JLM Audio Kits
Topic: JLM 60Watt Power AMP Kit
Replies: 261
Views: 695947

Re: JLM 60Watt Power AMP Kit

Hi Joe I have built the amp I got from your shop last Monday morning and it is going very well. Thanks for all your help. I believe there is a 'mod' I can do "With no volume control fitted the +/-vol pins can be used to do EQ like low end extension by adding a resistor and capacitor" What resistor ...
by Joe Malone
Tue Jan 30, 2024 11:02 am
Forum: JLM Audio Kits
Topic: MONO Ver2 Mic pre kit BUILD THREAD
Replies: 27
Views: 88124

Re: MONO Ver2 Mic pre kit BUILD THREAD

super, Joe, thank you! just to make sure I understand correctly, is the below roughly what you mean? And is there a way for me to understand how to calculate the value for R13/R14 correctly? If it's too complicated to explain, let's just say I'll stick with the NE5532A :) Yes that is correct. NE553...
by Joe Malone
Tue Jan 30, 2024 10:23 am
Forum: JLM Audio Kits
Topic: MONO Ver2 Mic pre kit BUILD THREAD
Replies: 27
Views: 88124

Re: MONO Ver2 Mic pre kit BUILD THREAD

If I'm building this, I'm thinking I might as well take the chance to customise it to my needs, and I'm wondering can I annoy you with a few more questions? I'd like to add a mute switch (with LED lit while muted), an extra Balanced TRS output, and an extra unbalanced TS out for using a tuner (only...
by Joe Malone
Mon Jan 29, 2024 11:19 am
Forum: JLM Audio Kits
Topic: JLM 60Watt Power AMP Kit
Replies: 261
Views: 695947

Re: JLM 60Watt Power AMP Kit

Thanks! That sounds like it should work. I want to run 2 or 3 AMP kits from that 300W PSU. Any suggestions how to implement a soft start or delayed start if that proves necessary? Start with no soft start and see if the SMPS can start the amp without going into hiccup mode. Soft start is easy but y...
by Joe Malone
Mon Jan 29, 2024 11:14 am
Forum: JLM Audio Kits
Topic: MONO Ver2 Mic pre kit BUILD THREAD
Replies: 27
Views: 88124

Re: MONO Ver2 Mic pre kit BUILD THREAD

oh super stuff, Joe, that is great. thank you! re the opamps, I was thinking of going the DIY route with either a pair of garOA10's or a pair of Pier Paolo's APP992's, if you think they'd work o.k.? I'm planning on ending up with a LOT of your JLM99v's in other equipment in the studio (I've already...
by Joe Malone
Mon Jan 29, 2024 10:27 am
Forum: JLM Audio Kits
Topic: MONO Ver2 Mic pre kit BUILD THREAD
Replies: 27
Views: 88124

Re: MONO Ver2 Mic pre kit BUILD THREAD

I'm considering using a Mono as an on-stage preamp for gigs. I'm trying to figure whether the output would be protected against phantom power inadvertently being sent to it. Would 'accidental' phantom coming in through the output XLR potentially fry the opamps? If so, I'm guessing either blocking c...
by Joe Malone
Sat Jan 27, 2024 12:03 am
Forum: JLM Audio Kits
Topic: LA500A opto comp MAY 2021 BUILD THREAD 500/51X
Replies: 108
Views: 184338

Re: LA500A opto comp MAY 2021 BUILD THREAD 500/51X

Everett wrote:
Fri Jan 26, 2024 11:38 pm
Fantastic! A little spray of pot cleaner did the trick. Both comps are calibrated and ready to go. Thanks so much for the troubleshooting help! Now I'll dive into building my FREQ500 kits.
Cool Great to hear that solved the problem :D 8)
by Joe Malone
Fri Jan 26, 2024 11:04 pm
Forum: JLM Audio Kits
Topic: JLM 60Watt Power AMP Kit
Replies: 261
Views: 695947

Re: JLM 60Watt Power AMP Kit

I'm not sure if resurrecting this old thread is the best place to ask this, but: Has anyone tried running AMP kits from a switching power supply instead of a transformer. For example this: https://www.aliexpress.com/item/1005005911546916.html I'm aware that there could be issues , specifically that...
by Joe Malone
Fri Jan 26, 2024 2:07 pm
Forum: JLM Audio Kits
Topic: LA500A opto comp MAY 2021 BUILD THREAD 500/51X
Replies: 108
Views: 184338

Re: LA500A opto comp MAY 2021 BUILD THREAD 500/51X

I think something may be grounded on the pot pcb on the faulty comp? When I disconnect the ribbon cable on the pot pcb and measure resistance from any lead to the case, I get readings. If I do the same on the good comp, I don't. When the ribbon cable is connected, if I measure resistance from any p...
by Joe Malone
Fri Jan 26, 2024 12:52 pm
Forum: JLM Audio Kits
Topic: LA500A opto comp MAY 2021 BUILD THREAD 500/51X
Replies: 108
Views: 184338

Re: LA500A opto comp MAY 2021 BUILD THREAD 500/51X

Everett wrote:
Fri Jan 26, 2024 12:20 pm
Resistor readings matched on SC pcbs for both comps.
Yes looks fine. How many dB louder is this comp compared to the off position with no makeup and no threshold?

With both comp on full makeup is there still the dB difference between the comps?
by Joe Malone
Fri Jan 26, 2024 10:54 am
Forum: JLM Audio Kits
Topic: LA500A opto comp MAY 2021 BUILD THREAD 500/51X
Replies: 108
Views: 184338

Re: LA500A opto comp MAY 2021 BUILD THREAD 500/51X

Everett wrote:
Thu Jan 25, 2024 5:42 pm
Ok, I swapped the BIO500T pcbs (not transformers) and the high level stayed with the faulty comp.
Ok points to the problem being on the sidechain pcb in the faulty comp. Can you take some photos of the top of that pcb so I can see all the resistor colour codes
by Joe Malone
Thu Jan 25, 2024 9:48 am
Forum: JLM Audio Kits
Topic: MAC Rack kit Build Thread from October 2023 with slow attack led
Replies: 39
Views: 25928

Re: MAC Rack kit Build Thread from October 2023 with slow attack led

Here are some pics of the meters after calibration with GR on and the LINK switch ON. They both were on -5db before I turned the link switch on. let me know what you think. Is this within spec? Photo Jan 21 2024, 4 46 13 PM.jpg Photo Jan 21 2024, 4 46 20 PM.jpg Not sure if these output spec look ok...