Search found 2066 matches

by Joe Malone
Sun Apr 08, 2012 9:06 pm
Forum: JLM Audio Kits
Topic: 8PAKAMP & 12PAKAMP KIT BUILD THREAD
Replies: 125
Views: 361387

Re: 8PAKAMP KIT BUILD THREAD

So the Wima 0.1uF is not ideal then? Will it be any issue if used? I'd hate to have to pull them all off. They will be ok since the PCB has very low inductance heavy power rails in its design. I'm not using the extra 20,000uF caps in the dual bridge - just the dual bridge part. No point to dual bri...
by Joe Malone
Sun Apr 08, 2012 9:30 am
Forum: JLM Audio Kits
Topic: 8PAKAMP & 12PAKAMP KIT BUILD THREAD
Replies: 125
Views: 361387

Re: 8PAKAMP KIT BUILD THREAD

The 0.1uF should be multichip mono bead type ceramics for super low ESR. Cut the front long legs of LM3886 at there knee joint and drop the IC in from behind the PCB. Any legs not used will hit solder joints and bend up slightly so you can push them up 90degrees and back a couple of times and they w...
by Joe Malone
Thu Apr 05, 2012 7:50 am
Forum: JLM Audio Kits
Topic: BA BA2 BA4 BAD Dual99v Build Thread
Replies: 376
Views: 870271

Re: BA BA2 BA4 BAD Dual99v Build Thread

Hi, I'm having a problem with my pair of BADs. With the left BAD connected, no problems. With the right BAD connected, also no problems. With both BADs connected, *and* with a microphone plugged in, there's what sounds like a ground hum - if the mic is unplugged the hum goes away, or if I disconnec...
by Joe Malone
Tue Apr 03, 2012 7:16 am
Forum: JLM Audio Kits
Topic: BA BA2 BA4 BAD Dual99v Build Thread
Replies: 376
Views: 870271

Re: BA BA2 BA4 BAD Dual99v Build Thread

audioboog wrote:Hi Joe

Thanks for your answer. Sending a picture of the input trafo. I think its a smaller kind then in the PM2000.
Bye Audioboog
bild.JPG
What is the Yamaha module that the transformer is mounted on?

As the circuit for that module will give use the info needed for the transformer loading.
by Joe Malone
Mon Apr 02, 2012 10:13 am
Forum: JLM Audio Kits
Topic: BA BA2 BA4 BAD Dual99v Build Thread
Replies: 376
Views: 870271

Re: BA BA2 BA4 BAD Dual99v Build Thread

Hi Joe I´ve just bought two BAD pcb:s. They look superb. I´m planning to use Yamaha-parts. GA8027 as input trafo, 80100 opamp and GA80281 as output trafo. Now to my question. Is there a possibility to get some tips for a BOM. Just to avoid problems. Thanks in advance. Bye Audioboog from Sweden Thes...
by Joe Malone
Sun Apr 01, 2012 6:43 pm
Forum: JLM Audio Kits
Topic: VU BUFFER KIT BUILD THREAD
Replies: 66
Views: 276032

Re: VU BUFFER KIT BUILD THREAD

thank you Joe for the reply :) 1. i would like to add a second trimpot and ON-ON switch to select between 2 calibration level, -18dBFS = 0dBVU (mixing), and -6dBFS = 0dBVU (mastering), where and how should i put the second trimpot and the switch on the schematic? You would have to switch a second t...
by Joe Malone
Wed Mar 28, 2012 9:33 pm
Forum: JLM Audio Kits
Topic: VU BUFFER KIT BUILD THREAD
Replies: 66
Views: 276032

Re: VU BUFFER KIT BUILD THREAD

1. i would like to add a second trimpot and ON-ON switch to select between 2 calibration level, -18dBFS = 0dBVU (mixing), and -6dBFS = 0dBVU (mastering), where and how should i put the second trimpot and the switch on the schematic? You would have to switch a second trim pot for the high gain setti...
by Joe Malone
Wed Mar 28, 2012 9:06 am
Forum: JLM Audio Kits
Topic: VU BUFFER KIT BUILD THREAD
Replies: 66
Views: 276032

Re: VU BUFFER KIT BUILD THREAD

For unbalanced signals do you mean tie both the + and - inputs to the signal source, or should one be connected to the source and one to ground? +in to signal center conductor of unbalanced cable and -in to shield of unbalanced cable. If using the circuit with a dual PSU, obviously the half-rail bi...
by Joe Malone
Thu Mar 22, 2012 9:43 am
Forum: JLM Audio Kits
Topic: 8PAKAMP & 12PAKAMP KIT BUILD THREAD
Replies: 125
Views: 361387

Re: 8PAKAMP KIT BUILD THREAD

Hi,... Can we cut/transform the 8pakamp pcb to 2x4pcb´s to a different boxes, for example? Thanks, Luís If you are very careful you could use a sharp Stanley / utility / box cutter knife to V score the top and bottom of the PCB against a metal ruler several times until the copper is cut and a good ...
by Joe Malone
Tue Mar 20, 2012 8:10 pm
Forum: JLM Audio Kits
Topic: 8PAKAMP & 12PAKAMP KIT BUILD THREAD
Replies: 125
Views: 361387

Re: 8PAKAMP kit BUILD THREAD

Joe...This is great news...I'll be getting my order in post haste. I know you will busy updating this thread with details like transformer details and bridge specs needed. Likewise the hook up notes for bridging and inputs etc. I think the pricing is very reasonable, and from the looks of thing a l...
by Joe Malone
Tue Mar 20, 2012 6:02 pm
Forum: JLM Audio Kits
Topic: 8PAKAMP & 12PAKAMP KIT BUILD THREAD
Replies: 125
Views: 361387

8PAKAMP & 12PAKAMP KIT BUILD THREAD

8PAKAMP kit is a 8 channel version of our popular 60W AMP kit. We originally designed the 8PAKAMP for a large Dolby Labs project we did a while ago. 8 x 75Watts of power configurable for making active monitors or full surround sound amp setups in lots of combinations on 184mm x 81mm PCB (eg 4 x 140w...
by Joe Malone
Tue Mar 20, 2012 7:57 am
Forum: JLM Audio Kits
Topic: BAN Build Thread
Replies: 132
Views: 410885

Re: Switched resistors for gain

Joe, I have 24-position switches, and I'm thinking of implementing 2dB gain steps. Assuming 1% resistors, how well matched would gains be between channels? Thanks! Paul HI Paul Easy one. With all resistors 1% there are 2 gain stages so 4 resistors all with 1% tolerance so +/-4% error. We do find th...
by Joe Malone
Mon Mar 19, 2012 8:32 pm
Forum: JLM Audio Kits
Topic: BAN Build Thread
Replies: 132
Views: 410885

Re: BAN Build Thread

Thanks Joe. That's all very clear. One last question: to cut on the gain attenuator steps (12 or so) I'd like to have a fine gain pot to cover inbetween (5-6 dB). I suppose this could be done tapping into the feedback loop of IC1 but, again, I'm not up to grasp if the DC present will play havoc wit...
by Joe Malone
Mon Mar 19, 2012 12:27 pm
Forum: JLM Audio Kits
Topic: LA500 opto comp leveling amp BUILD THREAD 500/51X
Replies: 223
Views: 592820

Re: LA500 opto comp leveling amp BUILD THREAD 500/51X

Hello Joe, I've recently purchased an LA500 (used, built by someone else) and ran into issues with calibration. I followed the instructions you've outlined methodically. I used a 1kHZ sine tone generated by "Test Osc" in Logic Studio through my Digi 003 interface. When I set it to -18dBFS, which is...
by Joe Malone
Fri Mar 09, 2012 10:28 am
Forum: JLM Audio Kits
Topic: JLM 60Watt Power AMP Kit
Replies: 261
Views: 694990

Re: JLM 60Watt Power AMP Kit

slb1959 wrote:Hi,...
Maybe i need to make 2 or 4 mono amps, but first i like to "see" how sound looks.
Do you have the same pcb to a sub-woofer amp?

Thanks, Luis
A pair of AMP kits can make a 140w amp for a sub but I do not have a sub filter PCB which should have a 12 to 24dB filter slope.