VP312DI 500/51x 312 Preamp...PROTO PICS ON PAGE 2!!

[horvitz]

Oh, nice!  Black and red should sound real good together ;D

This is going to use 16V and 24V?

 

[jsteiger]

Oh, nice!  Black and red should sound real good together ;D

Yes, of course...and with the gold immersion...look out  

This is going to use 16V and 24V?

It is selectable, either/or, but never both (for the DOA). Of course, a 51x rack is required for the 24V option, which is not a problem for yourself.  

Special care must be taken as to what DOA is loaded as a standard 2520 will smoke up rather quickly when supplied with bipolar 24V. Pier's APP2050E sounds rather nice in a 312 circuit running on 24V, BTW.

The HiZ Plug-In board is also selectable 16V or 24V. This selection is independent from the DOA V selection. For instance, one may want to run the Dan Kennedy HiZ FET Plug-In circuit on 24V for more headroom, while using a gar1731 for DOA running on 16V rails.

Options, options and yet more options.  ;D

Best, Jeff

 

[New Soul Rebel]

this looks like an exciting development Jeff. can't wait to chuck one of these in the control room, and another in my lunchbox.

Have to say, I quite like the idea of being able to build this as a DI box!

Is that humanly possible?

Matt

 

[jsteiger]

...Have to say, I quite like the idea of being able to build this as a DI box!

Is that humanly possible?

Do you mean as a dedicated DI only? Well, it could be built as DI only version but you would only have the Bo mode DI, straight into the DOA. Nothing wrong with only that. You would not need the mic input transformer then and it would not function as a mic preamp.

But... by adding the mic transformer, you get a full fledged VP312 mic preamp also. Plus, you get the added option of using the awesome HiZ Plug-In DI PCB's. These are pre-2622 so they would not work without the input transformer in place.

I have the Rev B proto nearly built. I have a few missing components coming mid next week. I have plans to finish the prototype metal tomorrow. When I get my regular computer back (being scrubbed clean from vicious malware attack  ???), I will post some progress pics.

So far, so good.

Cheers, Jeff

 

[jsteiger]

The first Rev B has been built and tested. All is good! Lots and lots of tonal options.  8)





I did some experimenting with an APP2050E running on 24V. Nice!    Headroom for days.


And the Peter Purpose FET HiZ Plug-In.


Bo's DI circuit tucked all in under the Neutrik jack and the post 2622 relay board standing up vertically.


The auto-switching relay PCB activated by inserting 1/4" plug in the jack.


Don't mind the jumpers. I cut the 2 relay control tracks experimenting with how the relays were activated. I ended up right where I started so no changes on this little PCB after all.  ;D


A true proto faceplate. I relay like the sub mini toggles. They work great BTW. No problems.


The couple of HiZ plug-Ins I have on hand.


I am gonna make a little change near the 2 slide switches. I am adding 2 more power rail decoupling caps so that all 4 power rails always have decoupling. Currently, the caps follow the DOA voltage select switch. That's pretty much it. Then we're off to the races!

BTW, rumor has it, Ed is working on his very own DI transformer. That will be killer indeed! 

Best, Jeff

 

[horvitz]

Outstanding, Jeff!  Really looks fantastic  ;D

 

[Ryake]

This looks great, I'm very excited to pick up a pair when they're done  ;D

 

[[silent:arts]]

nice teaser ;D ;D ;D
nice work

need to look in the other plug-ins ...
however, up to now you already have 5 (incl. Bo) HiZ options

btw, I want two of them, full kits

 

[jsteiger]

...btw, I want two of them, full kits

Duly noted Volker.  8) 

Maybe there will be some sort of barter in our future...Mr. 51x-AOC man.  ;D

 

[Winetree]

Jeff,
Have already built 2-VP26 and 3VP312's.
I am just waiting to get two of these Kits.
Robert

 

[gar381]

Very nice Jeff..

Beautiful engineering !!!

You have been a VERY VERY VERY BUSY LAD INDEED!! ;D

GARY

 

[jsteiger]

Thanks guys. You both Rock!  8)

This morning, I placed an order for a few hundred of the VP312DI aluminum faceplates. I am doing the back milling (for the 3 sub mini switches) in house (on a CNC router) to save a few bucks as I thought my metal shop's price was a little too much for something so simple. These should be to me in about 3 weeks. I will also offer these "raw" for a DIY finish.

I will order the VP312DI L-brackets in about a week or so since the faceplates take longer with the milling, printing and clear coat lacquer.

Final couple changes on the PCB will be done today. If I get the chance, I will order the next one there later today. After messing with a few things, I ended up moving a lot of stuff a little bit. Mostly to allow more fat-finger space around the HiZ Plug-In. It was a little tight between the input tranny and the Plug-In. Workable for sure, but since I am eating another tooling charge...what the hey! Better is always better right? 

Best, Jeff

 

[matta]

Jeff,

Not sure how you do it  It looks fantastic and no doubt sounds amazing, jam packed with goodies, look forward to hearing your thoughts on the various DI boards  ;D

Cheers

Matt

 

[babyhead]

Will you be able to send a post DOA signal to an amp with this design? A Pre/post amp feed is a nice feature.

 

[dandeurloo]

Jeff, you are a nasty nasty man!

 

[jsteiger]

Will you be able to send a post DOA signal to an amp with this design? A Pre/post amp feed is a nice feature.

Do you mean like for reamping? I did not incorporate that feature. I had heard rumblings that reamp module was in the works somewhere around here.

Jeff, you are a nasty nasty man!

Why, thank you Dan. (I think??)

 

[babyhead]

Will you be able to send a post DOA signal to an amp with this design? A Pre/post amp feed is a nice feature.

Do you mean like for reamping? I did not incorporate that feature. I had heard rumblings that reamp module was in the works somewhere around here.

No... for recording a DI and amp signal at the same time.