Search found 25 matches

by tubegeek
Mon Oct 14, 2013 8:17 pm
Forum: Pro Audio Design
Topic: Using the LM317/LM337 as Shunt Regulators/Zeners
Replies: 1
Views: 7026

Re: Using the LM317/LM337 as Shunt Regulators/Zeners

Very very clever. You had me scratching my head at first with the pos/neg info...
by tubegeek
Fri Aug 09, 2013 6:43 pm
Forum: Pro Audio Design
Topic: DIY LED Strobe.
Replies: 19
Views: 26518

Re: DIY LED Strobe.

I feel like you are working a little too hard to amuse drummers - don't they usually amuse easier than that?
by tubegeek
Fri Aug 02, 2013 6:05 pm
Forum: Pro Audio Design
Topic: DIY LED Strobe.
Replies: 19
Views: 26518

Re: DIY LED Strobe.

I would think that having visual feedback in that application could make a large difference in how easy it is (for some people) to get consistent results. Very interesting idea.
by tubegeek
Mon Jul 08, 2013 1:35 pm
Forum: Pro Audio Design
Topic: Presenting "The Leslieator" - a work in progress
Replies: 10
Views: 17499

Re: Presenting "The Leslieator" - a work in progress

Running the mics from full rated voltage will buy a couple dB more headroom. I don't know what the ratings are for sure on these particular capsules, I don't have a part number or a data sheet at the moment. Similar capsules seem to be rated at 10V, though, and I may indeed tweak the adjustable vol...
by tubegeek
Sun Jul 07, 2013 11:57 pm
Forum: Pro Audio Design
Topic: Presenting "The Leslieator" - a work in progress
Replies: 10
Views: 17499

Re: Presenting "The Leslieator" - a work in progress

The circuitry is working perfectly, thanks for the help with it, Pros! Now it's just a matter of tweaking. With the electret omnis, located just outside the Leslie cabinet's louvers, I get a lot of leakage from my other sources. (I had been using dynamic mics tucked INSIDE the Leslie cabinet previou...
by tubegeek
Sat Jul 06, 2013 10:39 pm
Forum: Pro Audio Design
Topic: Presenting "The Leslieator" - a work in progress
Replies: 10
Views: 17499

Re: Presenting "The Leslieator" - a work in progress

I installed an LM317 to regulate the mics' power node. It's adjusted to 7.8 V (the data sheets I've seen on similar electret capsules call for a max of 10V, and I didn't have the exact resistors handy to get 9V on the LM317) and the system is behaving perfectly now - at least, according to the 'scop...
by tubegeek
Wed Jul 03, 2013 5:21 pm
Forum: Pro Audio Design
Topic: Presenting "The Leslieator" - a work in progress
Replies: 10
Views: 17499

Re: Presenting "The Leslieator" - a work in progress

Update: Harsh, distorted sound. Accidentally I forgot to pan the two channels apart so I don't know if I heard a blend of one clean channel with one distorted, or what exactly. Looking at the scope, one channel was passing a strange waveform compared to the other. It's not exactly easy to get a pure...
by tubegeek
Mon Jun 24, 2013 3:58 pm
Forum: Pro Audio Design
Topic: Presenting "The Leslieator" - a work in progress
Replies: 10
Views: 17499

Re: Presenting "The Leslieator" - a work in progress

An update: My oscilloscope probes came in and I had a bit of time today to test the "Leslieator" out. It's working just fine and the oscillations went away as soon as I attached a clip lead between the body of the unit and my scope's ground connection. It just wasn't happy floating without a drain p...
by tubegeek
Tue Jun 18, 2013 3:58 pm
Forum: Pro Audio Design
Topic: Presenting "The Leslieator" - a work in progress
Replies: 10
Views: 17499

Re: Presenting "The Leslieator" - a work in progress

Thanks!

I have just nipped the mistaken R's, and shot a couple of pics of the build-up. Also the schematic is now corrected for 800 Hz and no R's shunting the virtual earth nodes.

I think my fb C's are probably at least a decade too large but ....

Thanks!
by tubegeek
Tue Jun 18, 2013 2:29 pm
Forum: Pro Audio Design
Topic: Presenting "The Leslieator" - a work in progress
Replies: 10
Views: 17499

Re: Presenting "The Leslieator" - a work in progress

That schematic looks OK from a quick glance. OK, thanks for the check-over. I would lose the 1.3k resistors to ground on U5a and b Oops! Thanks! I was making a standard feedback configuration, not a virtual earth mixer stage configuration. Duh. My First Mixerâ„¢. Look for a wiring mistake or other er...