Ideas for "Vox Box" type machine (LA-2a based)

[kiira]

[quote author="cjenrick"]Even with a remote pwr supply, I had a time getting all the EQP-1A stuff in a 1U box, but I used a lot of relays. If you wanted a MEQ and 1A in the same box, it would probably have to be a 2U rack job.
The Tremaine book recomends at least 100 volt caps for the passive section, which can get pretty big, especially the 1 uf and up stuff.
:guinness:[/quote]

Well, like I wrote in my first message, the case is 20+" deep and 3U and I planned on making each unit patchable independantly like duh acourse.

It's a moot point now because my mixer needs fixing first before I finish or start any other projects. FOO.

 

[Bear]

[quote author="cjenrick"]
The Tremaine book recomends at least 100 volt caps for the passive section, which can get pretty big, especially the 1 uf and up stuff.
:guinness:[/quote]

Chris, I imagine we aren't talking Johnny Tremaine here. What's the book?

Bear

 

[CJ]

Sorry, it was the Passive Audio Network Design download that was here a while back.
Let me know if you want a copy.
almost 300 page pdf.
cj

 

[Bear]

Well, I've gotta move, and I start law school in 2 weeks, but, yeah, what the hell, some light reading is always nice.

(Not just a gear slut, but a DIY slut.)

Bear

 

[JLM Audio]

Just a rough concept for a channel with mic pre / comp / EQ and only two opamp make up stages in it that could be done on the JLM99XMB.PCB

Joe

 

[digichild]

[quote author="JLM Audio"]Just a rough concept for a channel with mic pre / comp / EQ and only two opamp make up stages in it that could be done on the JLM99XMB.PCB

Joe[/quote]

very interesting-thank you,can you load it up in better quality please-i can`t increase it :sad:

 

[gary o]

Hi Kiira a while back I made myself a LA2A then I added a Altec 1566A mic pre & then a piltec MB1 & then a RCA BC2B & then a Jenson mic pre, its all in one box the box is only 12 x8x6 inches dont ask how it fits, seperate power supply tho, I have in out sockets & patch between them I got a bit carried away.
I got very intersted in the different sounds of the tube mic pre,s iv since d i y ed a RCA BA1A,RCA BA21A a V72 and a Mccurdy AU300 all in a similar box.
I dont know what the original versions of all these units sound like in comparison & iv only owned things like joe meek type stuff but sold it straight away after comparsons.
during my tube mic pre experiments I can across your mic pre from your sight so I soldered one up,{so thnks for that}, and it sounds great
IMHO all this DIY stuff sounds great but with slight differences & your one pre sounded great to me & added yet another flavour
I was wondering if your gonna need another pre with more level,when you add your LA2A your gonna have a lot more level anyway.
I just have a PC as a recorder I usually use a studio condenser mic into one of the above pre,s then into the LA2A into the PC the make up level on the LA doesnt go above 3 out of 10.
I also have a Beyer M260{lovely mic} to get the same recording level I just turn up the LA make 2 or 3 more notches


Cheers...... Gary O.

 

[Guest]

i think it's a fun idea to build a voxbox style rack.

, ive been working on a la-2 pcb so i could do just that ,


putting the la-2 circuit in to pcb format , the whole compressor is broken up in to 5 parts only 1 or two wires actually going from one tube to the next.

wich makes condensing it real fun , rather like a jigsaw puzzle ,

i thought i would do build a neve 1272 pre/ la-2 /and tringing to find an

eq that isn't as big in components as the pultec. the la-2 ive condensed to a 8x10 circuit board minus room for the power sup , and the ha-100x/a-24 . jensen xformers are small so im diggin on those ,

i could probably go much smaller on the la-2 pcb , but wanted to work out the kinks on a bit larger scale and use 2-3 mm tracks.

for some reason my 6aq5a was getting 230 volts through the r34(10k2w resistor)

had to replace that with a 68k 2w and the r35 (220k) with a 1 meg , now all the voltages are normal , but ive went over the circuit a million times

and every thing apears to be done correctly ,i am unsure if the pcb

format

makes a few paramiters different.

or i need to take a vacation.

groove on

 

[rafafredd]

[quote author="gary o"]Hi Kiira a while back I made myself a LA2A then I added a Altec 1566A mic pre & then a piltec MB1 & then a RCA BC2B & then a Jenson mic pre, its all in one box the box is only 12 x8x6 inches dont ask how it fits, seperate power supply tho....

I got very intersted in the different sounds of the tube mic pre,s iv since d i y ed a RCA BA1A,RCA BA21A a V72 and a Mccurdy AU300 all in a similar box...
[/quote]

Please, Gary. I NEED to see some pics of those boxes!!! Just post it. I like those crazy DIY style gear. It must look funky!!!

 

[gary o]

Hiya Rafa i'll try sort some pics only if you & the others dont laugh haha na ya can if ya like, remember these were experiments that worked so I kept them & added more ..got a bit out of hand.
Ive just changed to AOL & I think theres a way I can show pictures i'll get on it.

Cheers...Gary O.

 

[gary o]

What a knob! just realized Kiiras original post was way back in August.
Anyway heres some pics... if ive done this right, and this works i'll stick some better pics on soon,these projects are all still work in progress keep pulling them apart adding & changing bits all the time...dont laugh.

The pics should be

1. The inside of Altec 438 mic pre made for me mate.
2. left RCA BA1A, BA21A, BC2B, Siemens V72 & Jenson cascode mic pres in a box on top of that Federal AM864 vari mu limiter right bottom Mccurdy mic pre on top of that LA2A,Altec 1566A, RCA BC2B,Pultec MB1 & Jenson Pre in a box on top of that is the RCA BA6A
3. The inside of a Mccurdy AU300 mic pre
4. the underside mess of the BA6A


http://img.photobucket.com/albums/v232/goba22/altec438pre.jpg
http://img.photobucket.com/albums/v232/goba22/labaam.jpg
http://img.photobucket.com/albums/v232/goba22/mccurdydiyau300.jpg
http://img.photobucket.com/albums/v232/goba22/baunder.jpg

Cheers .....Gary O.

 

[rafafredd]

Very nice! I love those messy PtoP pics!

 

[CJ]

Lord Jesus. Now I don't feel so bad! :razz:

 

[gary o]

See I knew someone would laugh! :grin: haha I dont care, anyway you aint seen nothin yet! that BA point to point is the unmessy one i'll post a pic that will make your hair curl! that red box has 11 tubes & three transformers all point to point (not a PCB fan} you cant see the tubes for wires.
When I first went on my quest to hear what the old tube stuff sounded like I really didn't have a clue, not that I know much now, but it taught me lots messin with this stuff with some great advice from a whole load of you guys too so thanks for that, im having great fun learning, singing is my living & I love singing with this gear it sounds great to me better than anything I could afford to buy
I'll post some scary pictures soon for a laugh.

Cheers ...Gary O.