GSSL and DBX 202 Black Cans, anything i should know?

[gerardmanvuca]

i'm about to lay these into my gssl and was wondering if there are any changes i need to make? i've been lookin around the forum but cant see much info on he black cans....i have a feeling im guna have to switch sum resistors but not sure. any help or helpful pointing in the right direction wud be well apreciated....cheers

 

[signalflow]

The GSSL was designed with the 202 originally, so I don't think there is going to be anything to change over.  Take a look at the schematic and you will see that it shows the black can in the signal path with a note by it stating "202 or THAT2150 emulation circuit".

Also this should probably be in the GSSL META.

-Casey 

 

[strangeandbouncy]

not sure if you're correct there,


  i htink that it was done for 202c(gold can), and I think they are different(?) Sorry. too busy to search right now, and I am sure that the relevant info is here, or elsewhere on the web

 

[signalflow]

I'm just going off of what is stated in the schematic.  It is labeled as a 202 in the schematic and a 202/XL in the box with the emulation circuit.  I personally have a pair of 202C's I received from Keith about 2yrs ago but have not fired them up in the circuit yet.

Upon futher investigation Gyraf's SSL page describes them as 202/XL.

From the website:

"This substitute circuit is based on reverse-engineering a 202XT VCA - it turned out to consist of ten paralleled 2150’s with a common low-impedance buffer for the control inputs. So this is the substitute, but done with only one THAT2180 (or 2181)."

Maybe some folks who have used different variations on the 202's can chime in and give their findings as far as parts replacement.

But again this should be moved over to the GSSL Help thread.

-Casey

 

[strangeandbouncy]

202xl is not the same as black can 202, iirc. I think that 202xl is swappable with 202c iirc. 202c is discrete, and 202xl has ic's.


    someone . . . ?


    KIndest ergards,



  ANdyP

 

[strangeandbouncy]

Actually,


I am wrong! 202c AND 202xl do not have same gain control constant. I have attachpdf of all the details. 202 is different again, with -6mv/V.


   ANdyP

 

[DrFrankencopter]

The gold ones (c version) were a better grade and like the later integrated versions were achieved by higher selection. When SSL started using them and sales increased dbx could not meet the demand so they made a pin compatible 202x out of *reject* 215x parts.

Black and gold should be the same as far as surrounding component values go. I've got 4 black 202VCA's kicking around. If there's interest, I'll dig them up and put em on the black market.

The dbx202X and 202c need different supporting components. Input and output resistors must be skewed by 1.25k (output resistor needs to be larger than the input) to maintain 0dB with 0V at the control port. Control port impedance is different too...but won't matter if the port is driven directly by an op-amp.

Cheers

Kris

PS: I've got some old fax's with this information in better detail. I'll try to host them later this week.

 

[strangeandbouncy]

Hi, good DrFrankencopter,


  did you not just see the PDF file I attached? All the datsheets for 202, 202c, 202x, 202xl, 2001, 202xt are there, and easy to read . . . .



    Kindest regards,



      ANdyP



     

 

[Biasrocks]

Black and gold should be the same as far as surrounding component values go.

I'm finishing up my 202C Gold Can vca, 2150 sc vca  GSSL, I used the original recommended values for the input resistor (15K vs 27K) and the ratio resistor (100K vs 127K).

All is fine with those values here.

Mark

 

[DrFrankencopter]

Hi, good DrFrankencopter,


  did you not just see the PDF file I attached? All the datsheets for 202, 202c, 202x, 202xl, 2001, 202xt are there, and easy to read . . . .



    Kindest regards,



       ANdyP



     

Oops, I had missed it. I see it now. Good stuff (same as what I have).

Cheers

Kris

 

[signalflow]

Then from the descriptions above I myself do not have 202C's.  Mine are just black no markings, image below.  Does anybody know which these are?

EDIT: On further thought these could be the same as what is in the first post just without the stickers......

-Casey

 

[DrFrankencopter]

Those are regular 202's...

Cheers

Kris

 

[signalflow]

ahh thank you, so I guess both gerardmanvuca and I now have very similar questions....one could say identical.

-Casey

 

[RedNoise]

I also got a pair of non marked 202s , certified dbx black cans from a famous member here...

 

[Tekay]

All you need to know! http://www.thatcorp.com/datashts/dn127.pdf

 

[signalflow]

So from what I gather from the dn127 data sheet the input and output resistors need to be swapped out and everything is kosher.  The data sheet rates them both at 100k and gyrafs schem calls for 27K on input and 15K on output.  That seems like quite a large jump in values to me.  Is there a formula that I need to be using to find the proper input and output resistors, or do I simply just swap those resistors out?

Thanks,

-Casey

 

[gerardmanvuca]

So from what I gather from the dn127 data sheet the input and output resistors need to be swapped out and everything is kosher.  The data sheet rates them both at 100k and gyrafs schem calls for 27K on input and 15K on output.  That seems like quite a large jump in values to me.  Is there a formula that I need to be using to find the proper input and output resistors, or do I simply just swap those resistors out?

i'm wondering the same thing...it does seem that its a straight swap for 100k which would kinda make sense as my make-up gain knob seems much more sensitive now.it does seem like a big jump to 100k but in the dbx202c schem it sais to use 50k which is also a fairly big jump in comparison to the 202.........Also i'm a little confused about the in/out caps...it sais to use a 2u2 whilst gssl is a 22u? plus the out put cap sais 10p instead of 100p in the gssl.....so 10x times smaller on both counts... do i need to change these aswell? i'm guessing yes but i'm not proficiant enuff in electronics to have a clue about this......Anyway im going to follow this schem and put in 100k on in and out and just leave the 22u and 100p cap in there........i'll report back when i've done it. hopfully its not going to fry anything...a bigger resistance shudnt do right!!??

As for the control voltage i've no idea what mine or the gssl in general is rated at (im guessing it depends on the sidechan VCA?). theres quite a difference between the gold can and black can, the gold being a recomended -50mv/dB, whilst the black only -6mv/dB.

Also i've linked to this thread in the gssl help thread. might be a good idea to keep the info concentrated here involving the DBX black cans as the main thread gets questions interupted a lot with other issues and somtimes questions get lost in the jungle...if u knw wat i mean......I have searched through the help thread but havent found much helpful info on the black cans specificaly, in there......maybe this can be added to the gssl meta at sum point if we get sum good info going.

 

[Biasrocks]

The notes are general guidelines for implementing the VCA.

I would stick to what SSL used in their design.

There are minor differences from what's implemented in the GSSL, such as the 22uF coupling cap instead of 2.2uF, but this is actually an improvement and can be left as is. There's more decoupling of the power rails in the SSL version and the 15K input resistor (27K in your schematic) is specified in the original version of the GSSL using the 202 vca.

My suggestion is to build it as you were using a 202C and tweak it, if necessary once you get it up and running.

Mark

 

[bruno2000]

I have several Black 202s.  PM me if you want to try them.
Best,
Bruno2000

 

[gerardmanvuca]

Cheers for the insight mark.thats helped clear it up in my head a bit..i guess it makes sense to wire it like the ssl. I actually wired both; 15k on ins/outs and 100k on in/out and didnt notice much diffrence in sound or level (there might have been some, but nothing noticable after a re-stuffing break).  The VCAs seem to be working fine. Passing audio, compressing, and the sound quality is really sweet compared to the THAT 2180LC's i had before. There are some attack/sidechain issues still to iron out but i had these before the black cans were installed anyway.