REDDI DI

[evil grill]

Nice Hammond-case you can get in Germany:

http://www.tube-town.net/ttstore/index.php/cat/c389_Hammond-Module-Instrument-518-Se.html

 

[irfrench]

Evil Grill - Thanks for pointing those out.

Today I've had a go at learning SketchUp (following Gemini86's use to show how the GIX preamp fits together), initially I was trying to fit two channels into a smaller case off eBay - but no dice.  The Hammond case suggested by EG however works quite nicely.

I've got parts on order so hopefully I can get a quick hook-up done to see how she sounds.

Cheers,
Ian

 

[Beeswax]

I recently had the opportunity to meet Pete Montessi of A Designs and Reddi fame.  Very sweet guy and a some great gear coming out of his shop.  I'm very interested to see how this tube DI project evolves though and I am awed moreover by Ian's tube console creations.  Remarkable. 

 

[erikb1971]

I'm going to use the PSU case from Dan at Collective Cases ($85)

Yeah, my plan was to be able to use the PSU cases for a number of things like this or a tube preamp case as well.  I suppose I could do a special run of them in a different color if enough guys could agree on it for this project.  Maybe Red?  haha

I would be in for a red one! Or any other colour... but red would be nice!

 

[irfrench]

Evening all.

I've proto'd one channel 9622 as SRPP.  It sounds great and as said before I'll get some sound samples together soon.

Wiring is pretty ugly, obvs it'll need sorting on boxing but it's pretty quiet now anyway.

It's definitely got a character - 'round' is probably a good word.  It's not massively 'gainy' when dealing with passive bass so if you want distortion this isn't the way to get it.  Then again, it's meant to be a DI not an effect!

Output wise with a passive bass I'm getting signal levels where I want them (peaking around -12dBFS) so I'm happy.

Thanks again to Ian (ruffrecords) for his help and generosity.


Cheers,
Ian

;D ;D ;D

 

[irfrench]

Hi all.

THREAD RESURRECTION!

As mentioned/promised - I've gone done some samples:

http://www.groupdiy.com/index.php?topic=51639.0

Hope they are useful.

Ian
;D

 

[ruffrecords]

Nice Hammond-case you can get in Germany:

http://www.tube-town.net/ttstore/index.php/cat/c389_Hammond-Module-Instrument-518-Se.html

As far as I can make out these are all steel. This means the front and back panels are steel and I always find it a PITA to make XLR holes in steel - I even broke a Q-Punch making a hole in steel once.

Is there a version with aluminium front and rear panels??

Cheers

Ian

 

[dirty1_1garry]

Hello folks!

Couple days ago had some experience with R DI. And it sound really impressed! So I could not resist to watch what is inside 
I've got schematic that pretty close to schematic posted by Michael Tibes on page 2.
I found that out level pots value is A1K = 1K log.

will post power schem in the future.
Power transformer gives 200VAC and 8VAC. After power pcb it gives 6.23V for heaters and 173V B+.

The main question is steel about SE out trany.

For understanding of levels inside of schematic I've done some mesurements. Could contain errors but here is what I measured:
send 1kHz 0.775V signal to the input via mono jack
get 6.76V - 8.66V between xlr out pin2 and pin1 (1k log pot min - max)
get 6.28V - 9.8V between out transformer primary wire and gnd.
get 12.8V - 24V between out transformer primary wire and B+.
get 2.6V - 5.3V between out transformer secondary wires.

 

[ruffrecords]

Well done for taking the time to trace out the schematic.

What instrument did you use to make these measurements?

Are you sure the pot is wired as shown on the schematic?

Cheers

Ian

 

[dmp]

Very cool!
If you measured the voltage on the 220 cathode resistor, you could work out the transformer DC current.

 

[dmp]

So on page 2, CJ posted a design for an output transformer for this circuit.
My question is how to buy the materials?
The lams are here:
http://www.magmet.com/lamination/625ei.php

Is there someplace that sells them in small quantities? Or can you buy from magmetal if you contact them directly?
Also need a place to buy the bobbin, channel frame, paper .005", and wire for 3600 turns on the primary and 900 on the secondary for 4:1 (wire gauge?).
Any help would be much appreciated!
- Dan

 

[bubbi]

So on page 2, CJ posted a design for an output transformer for this circuit.
My question is how to buy the materials?
The lams are here:
http://www.magmet.com/lamination/625ei.php

Is there someplace that sells them in small quantities? Or can you buy from magmetal if you contact them directly?
Also need a place to buy the bobbin, channel frame, paper .005", and wire for 3600 turns on the primary and 900 on the secondary for 4:1 (wire gauge?).
Any help would be much appreciated!
- Dan

For the core, probably the best option right now would be edcor, they sell core material in small quantities: http://www.edcorusa.com/p/1045/ei63
Magmet don't have the M6 steel you want for this and they usually don't do very small orders.

For wire I use tempco on ebay, they are really nice and have everything.

It will probably be hard for you to find bobbins in small quantities but maybe you can get samples from cosmocorp?
Otherwise you could just make them from kraft paper and superglue.

-b

 

[dmp]

Magmet don't have the M6 steel you want for this and they usually don't do very small orders.

Why do we want M6 grain oriented steel instead of the High Nickel alloys?

 

[dirty1_1garry]

Well done for taking the time to trace out the schematic.

What instrument did you use to make these measurements?

Are you sure the pot is wired as shown on the schematic?

Cheers

Ian

I send signal from my DA card with unball jack cable. But... that could be not correct
Yes, pot is wired correctly.

 

[dirty1_1garry]

Very cool!
If you measured the voltage on the 220 cathode resistor, you could work out the transformer DC current.

just measured. Voltage on the 220R = 1.84V DC.

 

[dirty1_1garry]

Are you sure the pot is wired as shown on the schematic?

 

[dirty1_1garry]

Pot wire - orange and black. They go to 300R resistors that connect with TR secondary.

 

[dirty1_1garry]

I've done some more measurements using reamp box. It should be more correct. Coming soon!

 

[dmp]

just measured. Voltage on the 220R = 1.84V DC.

Thanks!
So i=8.4mA per stage, for 16.8mA through the Transformer.
CJ must have had some insight since he spec'd a transformer for 20 mA DC.

 

[dirty1_1garry]

Here some more photos:
http://www.flickr.com/photos/95158972@N07/

I done a new measurements with using reamp box, so I've got correct guitar level/ impedance signal.
I send 1kHz from DA to reamp, get 0.775V from reamp and send it to DI input. Than measured some parameters of schematic with gain pot on minimum and on maximum. See results at link on top.