DIY thread.....

  • Thread starter Thread starter thane1200
  • Start date Start date
JerAy said:
You guys ROCK! Thanks! Im no expert but i like to share what little i do know! Frederic, I'll contact you soon. ( like your work space!) I built my own 2 bay racks, 2 track and stereo equipment racks out of wood. If anybody wants plans, let me know and I'll draw some up and shoot them to Fredric. You can make the 2 bay a 1 bay EZ! See pics.
Click to expand...

JerAy,

Are those three Deltalab Delay units I see? (The blue rack pieces)

if so, awesome! I had two Effectrons back in the 80's, and I lovedthem but when we sold our sound system, they went with it. I wish I had kept them because they rocked!


Tim
 
JerAy said:
cowboyj and frederic, im sorry for not getting the schematics out to you guys yet. i have a draft version but time is not on my side this week. also, i may move out of state. my studio that i just spent 2 1/2 years building will have to be torn down. just finished it last month! im almost ready to call it quits.
Click to expand...

No problem Jeray, I totally understand the lack of "round tuits". I have the same issue as well from time to time.

If you want to send it just to me, I can make it available on the web for everyone else, if that saves you any time or aggrevation. More than happy to do so.

Sorry to hear your studio is going down... been there done that... make sure you get your script for prozac filled. I suffered for about a year afterwards.
 
I've got a question for some of you guys who are more knowledgable about electronics. I'm just a tinkerer, myself. :D

How feasable would it be, to use some of those little amplifiers to power headphones? I mean - for $15 to $20 per channel to power Headphones - that's not bad (essentally build one little amplifier kit for each pair of headphones.

One of my questions is - if you were to do this - how would you figure out what size power supply you'd need to drive them all?

I've done things like - I have some old Omnicraft noise gates (GT44 I think is the model - they are orange and black) and I installed 1/4" TRS jacks in them, with the send and receive on the same jack - that allowed me to only have to drill 4 holes in the back of the case, and could plug them directly into my TRS inserts on the mixer for live use.

And I have rebuilt 2 mixing boards - but any monkey could do that if trained right. LOL I just repalced parts with the same kind of parts - I didn't really learn anything other than 6 months of soldering on a 24x4 channel board kind of sucks. (It was an Old Kelsey that I totally rebuilt, a friend helped me electronically split the board into a pair of 12x4 boards - so that we could use it for 8 track. We just cut the busses in the middle, and he made a little gain stage panel with knobs on it to control the volumes of the busses.)

Actually, even though it was an old cheap mixer -I kindof liked the sound of it, although I would have liked to have lowered the Q of the Lows on the EQ section.... but I don't know enough about that.

This isn't my mixer, but it's the exact same model.


Thanks,
Tim
 

Attachments

  • kelsey-6.webp
    kelsey-6.webp
    32.6 KB · Views: 188
if you're DIY'ing a headphone amp, the way to determine the power requirements in watts is to look at the op amps (or LM386 and so forth) chips you're going to use, and look at the maximum ratings. If you have four such chips, multiply the max ratings by four, then add 20% for a margin.

I didn't get a chance to look at the kit page you did, but make sure the amplifier uses something other than an LM386. It's not a bad chip for toys and such, but for a studio application you'll find the frequency response is not even close to flat. And as you push the chip to about 1/2 it's rated maximums, it gets even less flat.

Another kit is from PAiA:

http://www.paia.com/hda.htm
Schematic: http://www.paia.com/hdasch.pdf

The PAIA schematic doesn't include the chip identifiers, because they want you to buy the kit. However, they are LM5532 dual-ip amps which are really nice, clean op-amps for very little money. If you're super cheap, you can also use TL084 op-amps but the output will be a little less.

BTW, in their old 8-bus consoles, Mackie used to use the 5532 op-amps to drive their headphone jacks, as did some fostex top-end consumer grade stuff.

I've made gear over the years when I had more free time to tinker, and enjoyed it immensely. I always struggled to enclose it into a rack enclosure, but nowadays a lot of companies make nice 1U, 2U and 3U enclosures that you can drill holes front and back, and shove your stuff in. A manufacturer called "Hammond" is my personal favorite, but there are others. Mouser and Digikey carry the Hammond product line. Bud also is nice stuff. Like so:

http://www.mouser.com/catalog/624/1375.pdf

For me, if it can't go in a rack, I don't want it.
 
frederic said:
For me, if it can't go in a rack, I don't want it.
Click to expand...


Thanks Frederic! I feel the same way - my entire rig (based on a pair of DA38's) is rackmounted in 2 racks. One has the recorders, DAT, and headphone amps in it, the other has a Mackie 1604VLZPRo with the outboard beneath it. I've wired up some patch panels and I just patch the 2 racks together - all of the outboard gear is pre-configured inside the rack, so it's "plug & play". I set the thingg up to be a portable studio so I can haul it out to band rooms and stuff like that.



Tim
 
frederic said:
The PAIA schematic doesn't include the chip identifiers, because they want you to buy the kit. However, they are LM5532 dual-ip amps which are really nice, clean op-amps for very little money. If you're super cheap, you can also use TL084 op-amps but the output will be a little less.
Click to expand...

I looked on Mouser.com, Radioshack, and PartsExpress and can't find any LM5532 op-amp chips. Any other ideas on where to look? I'm considering building the headphone amp in a rack case.

Also, in looking at the schematic, I'm guessing that the pots are dual-ganged, any thoughts on what to use resistance-wise?

Thanks,

Jason
 
Fitz - Very cool stuff on your iso boxes. Can't wait to see your cooling apparatus as well. I haven't worried much about my computer noise since I don't record anything inside my control room except bass on a DI, but last weekend during a session I was sitting there thinking about how noisy that PC was, so your project posting was perfect timing for my thought processes.

Have fun ;)

Darryl.....
 
Very cool stuff on your iso boxes.
Click to expand...
Hey thanks Darryl, I 'ppresiate the comment. Actually, there is more. I have lots of little projects that are starting to come together. Most of em are a result of designs that I drew almost 15 yrs ago. Ha! I love to build stuff, so I tend to tinker with this stuff untill I get it the way I WANT IT! :D Thats why it's taking me so long. Here is an example. In this section you can see a linear motion track and carriage that support a variety of things, like 2 removeable keyoard/mouse trays, a clipboard tray, an all purpose tray, for things like remotes etc. , The pics show it before the last armrest is put in place. The armrests have naughide covered pads. The 2 end armrest frames, contain a module that in turn, has two headphone output jacks, and source select switchs, and a hi impedence input and send distribution switch. Thats whats the last pic is. Anyway...have fun too, and thanks.

CONSLDTL2.gif

keyboard track.jpg

32.jpg

30.jpg
 
Also, in looking at the schematic, I'm guessing that the pots are dual-ganged, any thoughts on what to use resistance-wise?
Click to expand...
I used 100ohm. In the pictures above, there is a headphone distribution circuit that is resistance based. However, I "gleened" the circuit from a commercial distribution units that are daisy chained as required. They have two outputs, two volume, an XLR input(wired for a headphone level output from a source) I added some source selection switchs into the circuit. I drive it with a small reciever :D Up to 6 of these units can be daisy chained. As it is, I have two of these "units" custom made for my console. It also has a hi z input for plugging in anything like a guitar, bass, keyboards etc. There is a "send to source A/B/C switch, to send the signal direct to the board, or to effects units on the console, which in turn send the Stereo outputs to a small Stereo tube amp, and a seperate set of small guitar speaker cabs on each side of the console.
However, I am interested in the op amp thingys :confused: you and frederic are talking about too. Are those amplifyers and what type or level of signal do you send to them.
hey frederic...HOWDY DOODY! :D

fitZ
 
RICK FITZPATRICK said:
However, I am interested in the op amp thingys :confused: you and frederic are talking about too. Are those amplifyers and what type or level of signal do you send to them.
hey frederic...HOWDY DOODY! :D

fitZ
Click to expand...

Howdy howdy.

Most of the above circuits I posted, for headphone amps, are suitably fed +4db signals, unbalanced, unless you rig up a simple additional op amp per channel to handle the balancing inputs. Easy to do, I can draw something up if nagged often enough.
 
Man,

I have to say, in all honesty, some of you guys simply amaze me! :D

Frederic is a wealth of knowledge; I've learned a ton from reading his posts, and now Rick - you're building a desk frame out of freaking METAL! That is awesome!




Tim
 
Frederic, something like this?

Jason

Hmm.... my pic posting didn't seem to work... I hoped to post a schematic I drew up of the Rick's idea of using ballanced ins. More on this to come...
 
Tim Brown said:
you're building a desk frame out of freaking METAL! That is awesome!
Click to expand...

I stole some ideas from Rick. And a lot of this was "winged" with a tape measure :D

IM000766.JPG
.
IM000775.JPG


IM000781.JPG
.
IM000784.JPG


IM000785.JPG
.
IM000786.JPG


IM000791.JPG
 
Last edited:
cowboyj said:
Frederic, something like this?

Jason

Hmm.... my pic posting didn't seem to work... I hoped to post a schematic I drew up of the Rick's idea of using ballanced ins. More on this to come...
Click to expand...


Yeah, I didn't see a picture either. Click the "manage attachments" button just below where you type a reply, and as long as the picture is 100K or less, the BBS will allow you to upload it for people to click.

If you want to embed it, as I often do, you use the image tags. If you look at the top of the reply box, you'll see a yellow box with a green bump on the bottom, just to the left of the globe looking icon, that's the picture insert. Click that, then it asks you for the http://server/image.jpg information. Of course you have to have the picture hosted somewhere else already.
 
DIY Mixing Console

Since there is some interest in op-amp design, I'd be happy to start a new thread, and we can put together the basic building blocks of a modular mixing console, if you guys wish.

And you can use those building blocks to build a mic/line mixer with specifications that rival some of the "darn good" analog mixers that are out there. We could use the fairly common/inexpensive NE5532/5534 op-amps to do most of the dirty work, with a couple of more expensive, readily available burr-brown op-amps for the mic pres, for example.

I have a lot of this designed already... I'd just have to have the time to dissect my digitally controlled, large format design and pull out the analog bits and replace the digitally controlled potentiometers with more ordinary, analog stuff.

Assuming anyone is interested. Might one of you want to build such a thing? We could put the building blocks together so anyone could build something as small as a 4-channel, mono mic mixer, to a full-blown 64-channel, 16 buss analog monster.
 
Last edited:
frederic said:
Yeah, I didn't see a picture either. Click the "manage attachments" button just below where you type a reply, and as long as the picture is 100K or less, the BBS will allow you to upload it for people to click.

If you want to embed it, as I often do, you use the image tags. If you look at the top of the reply box, you'll see a yellow box with a green bump on the bottom, just to the left of the globe looking icon, that's the picture insert. Click that, then it asks you for the http://server/image.jpg information. Of course you have to have the picture hosted somewhere else already.
Click to expand...

Aha! There we go, the pic was waaaay too big. Let's see if this one works. I should not that I was on my old laptop at the time I drew up the schematic, so I did it in Paint. So yeah, please forgive the cheesey-ness. Also, I used some nonstandard representations since it came out better in Paint. Resistors are boxes, and the pot is a pot.

Jason
 

Attachments

Since there is some interest in op-amp design, I'd be happy to start a new thread, and we can put together the basic building blocks of a modular mixing console, if you guys wish
Click to expand...
:eek: YESSSSSSSSSSSS...
Only thing is......in your SPARE time? :confused: Riiiiight.:rolleyes: (just kiddin ya) :D I'd love to see it frederic...and maybe that headphone thingy too!
Oh, I'll p.m ya about that snake offer....was that an offer?:confused:

And btw, tonight I'll post some pics of the plenums.. :cool: I cut them out last night, and tonight I'm assembling them.
fitZ
 
frederic said:
Since there is some interest in op-amp design, I'd be happy to start a new thread, and we can put together the basic building blocks of a modular mixing console, if you guys wish.

And you can use those building blocks to build a mic/line mixer with specifications that rival some of the "darn good" analog mixers that are out there. We could use the fairly common/inexpensive NE5532/5534 op-amps to do most of the dirty work, with a couple of more expensive, readily available burr-brown op-amps for the mic pres, for example.

I have a lot of this designed already... I'd just have to have the time to dissect my digitally controlled, large format design and pull out the analog bits and replace the digitally controlled potentiometers with more ordinary, analog stuff.

Assuming anyone is interested. Might one of you want to build such a thing? We could put the building blocks together so anyone could build something as small as a 4-channel, mono mic mixer, to a full-blown 64-channel, 16 buss analog monster.
Click to expand...


Just make sure to use some big massive summing amps, and I'm down with it. Summing amps are where SO many consoles fall apart, after all. It'd be a fun project for me.


Light

"Cowards can never be moral."
M.K. Gandhi
 
RICK FITZPATRICK said:
:eek: YESSSSSSSSSSSS...
Only thing is......in your SPARE time? :confused: Riiiiight.:rolleyes: (just kiddin ya) :D I'd love to see it frederic...and maybe that headphone thingy too!
Oh, I'll p.m ya about that snake offer....was that an offer?:confused:

And btw, tonight I'll post some pics of the plenums.. :cool: I cut them out last night, and tonight I'm assembling them.
fitZ
Click to expand...

Rick,
My email was just to let you know what the cable was, to see if you were still interested, since you have first dibs and others expressed an interest.

OKay, I'll start a new thread in a day or two called "Homebrew Console" or something like that, once I have some time to tear out the analog portions of my design, and each week or thereabouts I'll post a little more.
 
You must log in or register to reply here.
Back
Top