Sound Skulptor: Pre's, Compressors, Tape Simulator, Professionnal Audio Kits

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Didn't Retro do a mic preamp with 2 tubes for the 500 series?
You’re likely referring to the Retro 500PRE, which has 3 12AT7 tubes. I actually came here to ask about its compatibility with the Sound Skulptor 501 single slot host.

@JPK, I have one of your 501’s and was wondering if it would comfortably host a Retro 500PRE or your MP566 (they are pictured together on your site, but I’m double checking for clarity). Also, which iteration of the 501 switcher (2 or 3) would work best if applicable here?

The 500PRE power consumption is as follows:

+/-16 Volts 155 ma. 48 Volts 3 ma.

I assume even the Switcher2 is sufficient with its +19/-19, so my question is more on the ma draw. (same question would apply to your own MP566 tube preamp being that it draws “less than 160ma.”

Also, since the 501 is well-vented, I have to assume heat would also not be a problem with either preamp?

Another question for you and anyone else with experience: which of your preamps would you suggest as a great versatile all-rounder colorful mic pre/DI that could also be used as a color box of sorts for passing individual tracks and mixes through? I have super transparent pres at my disposal already..would like something closer to the opposite end but suitable enough for passing full mixes through. I’m looking at MP566, AB528, and MP573 (with the latter two having the added appeal of relaying the DI through the input transformer).

Thanks in advance!
 
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DI503J and MU524 ordered and received last week, now assembled calibrated and tested !
Very nice and pro kit
This is my first jump on the 500 series, I'm basically not that fan of this format, but I need a small setup to hook my 50' tube synth to the DAW, and the SK DI fit all my need.
Beside that I can't stop myself to buy the varimu too...
Both loaded in a bento 6 that is easy to move around the studio

top notch recording rig
syth->tude DI->varimu->FUN

many thanks @JPK !

Cheers

ps:this is personal taste but the MU look better with black knobs !

503_524.JPG
 
I will defi itely grab two MUs when the funds are here and mine shall acquire black knobs as well.

Another topic: not that these need any tampering with at all, but what are the in and out transformer specs/ratios? Probably won't bother but if I have summet old with the right ratios lying around I might try it in there for shits and giggles ....
 
Hello

Question regarding DI503J setup/calibration @JPK

In tube mode, trim is set for equal loudness perception with saturation engaged.
How is the THD behaviour regarding this voltage divider before the CLC circuit ?
I have a quick check at REW but I'm not sure higher setting offer more THD ?
I ask because some may prefer gentle distortion or a more pronounced one, wile overall level could be set later in the chain.

Cheers
Zam
 
Hi,
This setting is post tube so it doesn't affect the level of distortion.
The distortion level is only affected by the input signal level.
Regards,
 
We are having an issue with one of our LA502 comps. Recently patched it in for a vocal take and, when engaged, all the low end disappears and there is a harsh noise that is signal dependent ( rises and falls with the input signal ) . There is no noise when the module remains patched but is in bypass mode. Any suggestions as to where to troubleshoot? Thank you.
 
The disappearing low end often shows that one side of a balanced signal is disconnected from the transformer.
Check if you can measure the input transformer primary DC resistance from the input XLR (between pins 2 &3) : 2.2k
Same thing for the output transformer secondary DC resistance from the output XLR (between pins 2 &3) : 22 ohms.
 
The disappearing low end often shows that one side of a balanced signal is disconnected from the transformer.
Check if you can measure the input transformer primary DC resistance from the input XLR (between pins 2 &3) : 2.2k
Same thing for the output transformer secondary DC resistance from the output XLR (between pins 2 &3) : 22 ohms.
Thank you for the suggestion. I will try it as soon as possible.
 
I finally had a chance to check this. We have two LA502 comps. The one in the offending 500 slot measures 2.057K between input pins 2 & 3, and measures 24.2ohms between output pins 2 & 3.
The second unit measures 2.69K and 23.8ohms, respectively. Are these within spec, or too far off? Should I re-calibrate / setup?
I checked patchbay cabling connections, and all seem OK.
 
Outputs seem correct.
The correct value for input is between 2k1 and 2k2.
Try to do the measurements directly on the modules, on the finger connector between pins 8 & 10.
Also check you don't have a phase of the signal shorted to ground for some reason.
 
Outputs seem correct.
The correct value for input is between 2k1 and 2k2.
Try to do the measurements directly on the modules, on the finger connector between pins 8 & 10.
Also check you don't have a phase of the signal shorted to ground for some reason.
Measurements between fingers 8 & 10 were the same as the XLR pin measurements for both modules. I'll have to keep checking cables/connections. So, it seems perhaps a balanced signal may have gotten un-balanced somewhere?
 
@Spiritworks
You can try to listen to the signal by connecting a wire from a monitoring input
- to SW1 (Ratio) top pins which is the point just after the input transformer,
- to test pin TP1 just before the output transformer.
This should tell you where does the bass loss happen.
 

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