Search found 323 matches

by nclayton
Fri May 22, 2009 7:20 am
Forum: Creative Recording
Topic: scratchy pot
Replies: 6
Views: 1544

It sounds to me like for some reason the audio opamp wants to run with some DC offset (which makes the pot scratch) and that for some reason the servo's only able to compensate it out when there's no signal. It might be a problem with the opamp, but I think there's also an internal passive offset ad...
by nclayton
Thu May 14, 2009 1:59 pm
Forum: Creative Recording
Topic: Toft ATB16, approx. 40dB high-end noise, and phantom power
Replies: 2
Views: 1324

Hi. I assume you mean -32 and -43 dB noise? Your Toft doesn't have high enough voltage rails to put out 43 or even 32dBv of noise (or anything else) since you're talking about 40 or so volts peak for the lower of those two. I'm not picking on you here....I think it's important to figure out how much...
by nclayton
Tue May 05, 2009 9:46 am
Forum: Creative Recording
Topic: Building a DIY Cooper Time Cube "garden hose" Echo
Replies: 44
Views: 30950

Has anyone searched AES for information about this? A lot of these kinds of things had pretty elaborate descriptions published there.



PS sorry to bump up a kind of old thread...this just looked interesting.
by nclayton
Tue May 05, 2009 9:42 am
Forum: Creative Recording
Topic: Building a DIY Cooper Time Cube "garden hose" Echo
Replies: 44
Views: 30950

if you look on the picture, in the centre of the spiral there's a little grey billet box that i can't find too much info on. all i know if this box is maintained at 1 atmosphere and is sealed tight, apart from that i can't find anything. anyone have any ideas what might be in there? or what it migh...
by nclayton
Sun Apr 19, 2009 10:50 pm
Forum: Creative Recording
Topic: If I wanted to build my own power supply
Replies: 16
Views: 2974

If they can share a common ground without causing you problems, you could get the +/- 12 volt and +/- 15 volt out of the same transformer and unregulated supply. Then use a separate 5 or 6.3 VAC transformer for the 5 volt supply. Dropping a 12 volt rail (unregulated 15-16 volts minimum) down to 5 vo...
by nclayton
Fri Apr 17, 2009 10:38 am
Forum: Creative Recording
Topic: If I wanted to build my own power supply
Replies: 16
Views: 2974

I'd say it would be sensible to make your own. They're easy to make. I think the JLM supplies are nice for convenience if you don't need much current and don't feel like making your own circuit board, but I don't think they have a version that's easily adaptable for 4 positive voltages including the...
by nclayton
Sun Apr 12, 2009 4:10 pm
Forum: Creative Recording
Topic: Anyone know what this Urei part is??
Replies: 4
Views: 1377

I assume you looked at the big block diagram scematic to see the plug in mic pre with an input transformer. You probably realize that's a simplfied diagram. It's clear from your photos that your module is pin for pin compatible with the one shown there even though it doesn't show the circuit details...
by nclayton
Sun Apr 12, 2009 3:04 am
Forum: Creative Recording
Topic: Anyone know what this Urei part is??
Replies: 4
Views: 1377

I'm pretty sure that's a mic input card for a 1620 mixer. Those mixers are kind of collector/cool DJ mixers, so it's probably worth a few dollars to someone. I would think it would be worth most as a part of one of those mixers...that is it's probably not special sounding enough to justify trying to...
by nclayton
Thu Apr 09, 2009 3:19 pm
Forum: Creative Recording
Topic: STUDIOMASTER POTENTIOMER QUESTIONS?
Replies: 2
Views: 1103

You're better off using linear pots than log pots there. Regular log pots will have really horrible taper. Unless you wire them backwards so that the gain goes down as the pot goes up. I assume that mixer has a typical sort of long tailed pair mic preamp. If so, and if a lot of the gain pots are scr...
by nclayton
Wed Apr 08, 2009 10:22 am
Forum: Creative Recording
Topic: power amp clicks, speakers shut off
Replies: 11
Views: 1558

Then again, if the amp only shuts down when it's on its side, it could be a ventilation problem, as someone already said. So......
by nclayton
Wed Apr 08, 2009 10:16 am
Forum: Creative Recording
Topic: power amp clicks, speakers shut off
Replies: 11
Views: 1558

Some amps have thermal protection, but 90% of the time the relay at the output is actually used on DC coupled amps to protect speakers from output offset voltage. It's timed to come on within a few second of when you turn the amp on so that the DC settles before the speakers are attached, and then t...
by nclayton
Sat Mar 14, 2009 3:31 pm
Forum: Creative Recording
Topic: DC Tube Heater Supply Help
Replies: 7
Views: 2669

So what was the genesis of this design? The design was on the power supply pcb. What I'd like to know is who designed it? And did they leave any documentation, theory of operation, etc? I find it a little bizarre that they'd split up the voltage to be ~+3.5V and ~-3.5V, rather than just ground and ...
by nclayton
Thu Mar 12, 2009 9:22 am
Forum: Creative Recording
Topic: Adjusting Reel Height on Tascam 38...
Replies: 8
Views: 2401

Re: Thanks!

When I bought the unit, the seller didn't inform me about this. The unit was well packaged. (Box in a box, tons of bubble wrap etc..) Do you think this kind of thing would have happened in transit? The unit was displayed with a reel of tape and a take up reel. How the hell could the thing function ...
by nclayton
Fri Mar 06, 2009 10:02 am
Forum: Creative Recording
Topic: 200 Watt dummy load
Replies: 11
Views: 1837

Hi. It's still unclear to me what you mean by "cutting out". You've never clarified whether that means the audio goes away completely, partially, or whether than means you blow a fuse. The problems are completely different. But either way, I don't think biasing your amp is going to solve the problem...
by nclayton
Fri Feb 27, 2009 9:15 am
Forum: Creative Recording
Topic: 200 Watt dummy load
Replies: 11
Views: 1837

I agree. Technically a dummy load is actually BETTER for your amp than speakers since its impedance is constant. It will be fine as long as your marshall has an 8 ohm output setting. I can't figure out if you're saying the amp blows a fuse when you push it above 5 or if the sound just cuts out and t...