Octo REDD47

[Pinchedez]

Hello Guys !
It’s time now to present my 8 channel preamps. One more version of the legendary REDD47.
This version is in-between the original cassette and the 500-51X idea.
My goal was to develop an evolutionary rack in which I could add or exchange vacuum tube modules with a proper 320V and 6,3V rails.
Of course I didn’t forget the 500-51X family. An extension adaptor and additional thread holes permit the insertion of classical DIY modules.
The whole 8 channel rack has been tested and exploited in different situations: live shows, post-prod studios and recording studios with great satisfaction.
The last experience was the recording of the last IRON MAIDEN album “The Book of Souls” at Guillaume Tell studio in Paris. Read Sonomag 418 # mars 2016. Every guitar and bass was recorded through microphones and Redd47. All channels where used !

Let me describe some characteristics of the module.
As the genuine REDD47, it has a maximum gain of 45dB gain. Actually more than 47db.
I adapted one more step attenuation: 0, -6dB, -12dB, -18dB.
It has a 48V power supply, an impedance selector, a -20dB pad, and a phase reverse selector.
A ¼ inch jack gives a “Direct Input” to the tube for instrument or asymmetrical line in, with an impedance > 1Mohm. Then the maximum gain is 27dB.
The Vu meter is calibrated +4dB for 0dB Vu.
The original trim of +/- few dB has been replaced by the output volume situated right before the XLR output. That means right after the output transformer in order to drive the module without saturating the recording input.

These kits are available in several versions:
• The housing rack itself Euro-500
• The Power supply all in one (+320V, +12V, -10V, +16V, -16V, +24V, -24V, +48V)
• The Power supply HT (+320V, +12V, -10V) if you have the standard 51X PSU.
• Cassette Kit with all components.
• Cassette Kit with only mechanical parts ( the ones you can’t buy ) + BOM for general pieces
I’m working on those points.
Call any time for more details !!

All the best

Jensen inside

 

[ruffrecords]

Pics don't work for me. The seem to point to the C: drive on your PC.

Cheers

Ian

 

[DjaiTeam]

No pics here too..

Best Regards,
Iwan

 

[My3gger]

Sounds very interesting, i would like to see the pics too.
A few thoughts, i'm sure you know and noticed all or most of them;
not sure if you are mentioning input pads, if so values under 18dB of attenuation don't work well. I have pretty good experiences with Bourns 600 ohms T pads, simple 1k pot like API used on outputs never gave problems either. Most users like either option along -20dB at the input, it allows them to easily set output levels and drive preamps harder.
Original max gain is 46dB, many of us get up to 48dB with original schematic when fine gain control is out.
I like it on guitars and bass too, also on many vocals with certain gain settings.
Did you notice 46dB position doesn't sound as good as the other two? With ussual 3 pos 4 poles switches it is possible to add one more position without NFB for those who like this kind of "rough" distortion. I think first two work much better than the last.

 

[Pinchedez]

Thanks for your comments.
Thank you for helping me with pics...
Ruffrecords: do you think this link will work ?

If not, whitch kind of format?

 

[Pinchedez]

I ment: "Users/Vaio2/Desktop/Images%20pour%20DIY/Vue%20g%C3%A9n%C3%A9rale.jpg" between
Thanks again

 

[Pinchedez]

Hello My3gger

The -20 dB pad is a resistive pad before the input transformer.
The output pot is 10K log situated (my mistaque in my first post)before output transformer. Even though the impedance viewed by the plates of 6922 varies, it doen't affect sound in any way.
I use a simple pot after the output transformer in an other module I will launch later on.

Original max gain is 46dB: Correct.
Many of us get up to 48dB with original schematic when fine gain control is out: Correct I have one @ 48.7dB
Did you notice 46dB position doesn't sound as good as the other two? very very light !

Bye

 

[ruffrecords]

I ment: "Users/Vaio2/Desktop/Images%20pour%20DIY/Vue%20g%C3%A9n%C3%A9rale.jpg" between
Thanks again

I do not think the board supports links to local files (on your PC) but you can upload a pic - there is an option for doing this below the text entry area when you write a post - it says Attachments and other options. Click it and scroll down a bit and you should see Attach: and a choose file box.

Cheers

ian

 

[[silent:arts]]

You can link to an external picture like this:

[IMG]https://static.wixstatic.com/media/8b61c1_1a0876d2a86547db9ff77e22418bc9d3.png/v1/fill/w_433,h_531,al_c,usm_0.66_1.00_0.01/8b61c1_1a0876d2a86547db9ff77e22418bc9d3.png[/IMG]

or attach one picture to your post:

 

[ForthMonkey]

WOW! It's special design!

I just wonder that hwew did you find knobs?I'm looking for knobs like this...

 

[Pinchedez]

Thanks to Ruffrecords and Silent:arts
That should help.
I try now to insrt some more pictures

 

[Pinchedez]

It works I have to resize them but.....

 

[Pinchedez]

Hello ForthMonkey,

The knobs used here are NOS MULTICOMP.
They are out of production right now.
I have them in black and re-anodize in sevral colors.
My usual stock or under treatement is:
Dia 12.7 skirt 19mm 1/4"> RED
Dia 12.7 skirt 16 1/4"> BLEU
Dia 9.7 skirt 12.7mm 1/8 > BLEU
Dia 9.7 skirt 12.7mm 1/8 > GOLD
Bye

 

[igrecji]

Hello,
We collaborated on numerous projects with Denis Pinchedez, and I had several times the opportunity to use the QUARANTE SEPT.
First of all, it sounds so great, very smooth at the top end, big lo-mid and bass, and with this subtle distortion by even harmonics which lovely improves the recorded source.
But in bonus, being at the origin of numerous innovations within the biggest P.A. COMPANY in France, the care and the quality brought to the design and the manufacturing of theses modules make a part of a rare beauty in DIY. Switchs is of an irreproachable quality, and the assembly too. Denis has designed an amazing TUBE DI BOX  (Three tubes) which I use personally in my studio and a lot of friends too.
We collaborated on a crazy project in 2011 when I had made in DIY 50 % of the outboards for the tour ZAZIE in Europe.
That is the reason why i ask him to adapt his rack so that he can receive modules in the  500 format as well as modules in the size 51x format.
Denis had helped me at the time of the tour to personalize the buttons which we had chosen for my modules.

http://www.mixaleaudemer.com/#!IMG_3105.JPG/zoom/ytakq/dataItem-il6m0bgg1

http://www.mixaleaudemer.com/#!NEVE%201073%20-%20NV%2073%20DON%20CLASSIC%20-%2016%20x%20Modules%20terminés%20pour%20la%20tournée%20ZAZIE%202011/zoom/rjwps/dataItem-il5grqgz

 

[ruffrecords]

Very nice build. Congratulations.

Cheers

Ian

 

[biosynth]

flag.
could be compatible with an api500 power supply? Apprently not, so how to do? thnx

 

[igrecji]

Hi Biosynth,
The rack as Denis Pinchedez say on his first post, can run with two power supply: one standard 500 or 51x for the API 500 format modules, and one for the retrobox gear like the QUARANTE SEPT mic pre. But you can have also the  The Power supply all in one (+320V, +12V, -10V, +16V, -16V, +24V, -24V, +48V) if you want it. It can drive all kind of modules, RETROBOX, API, 51x

Cheers

Yves

 

[Pinchedez]

Hello Biosynth,

As Igrecji said, my new rack can house all kind of modules.
Two connectors at the back; XLR 7ways for the standard 51X PSU and Amphenol C16 4 ways for tubes gear.
I mus add that the all in one PSU can drive 2 racks !
You can have a look on my first shot site: www.retrobox-audio.com

All the best

Bye

 

[biosynth]

ok I didn't understand you made a dedicated API500 rack. thanks