[BUILd] PM660 / PM670 SCAmp Booster build and tips help thread

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lolo-m

Well-known member
Joined
Dec 14, 2005
Messages
759
Location
Avignon, France
TO SAVE SOME TIME IN TROUBLESHOOTING, PLEASE READ ALL POSTS BEFORE IMPLEMENTING THE SCAB IN YOUR PM660/670. THANKS

Hi,
Here is a build help thread for poeple who choosed to implement my SCAmp Booster on their PM660 or PM670. Just to save some time, let's call it SCAB (SCAmp Booster  ;D)

Schematics :
http://nbns-studio.pagesperso-orange.fr/PM670/boost-analags-sc-amp.gif

Just a few soundsamples realised with the same settings using the two different modes . I'm sure the FAIRCHILD setting used in SCAB mode isn't what I would use to master this song but it is revelant of the different compression ways you can have using the SCAB:
Soundsamples :
Uncompressed file :
http://pagesperso-orange.fr/NBNS-Studio/PM670/UNPROCESSED.wav

Analag's way :
http://pagesperso-orange.fr/NBNS-Studio/PM670/pm670-analag-network.wav

SCAB Mode using Fairchild Position 2 setting :
http://pagesperso-orange.fr/NBNS-Studio/PM670/pm670-scab-fairchild-pos2.wav

SCAB Mode using custom Fairchild type TC network :
http://pagesperso-orange.fr/NBNS-Studio/PM670/pm670-scab-fairchild-custom.wav

Drum sounsamples :
Uncompressed :
http://pagesperso-orange.fr/NBNS-Studio/PM670/DRUMSNOCOMP.wav

Analags network :
http://pagesperso-orange.fr/NBNS-Studio/PM670/DRUMSANALAG.wav

Fairchild position 2 :
http://pagesperso-orange.fr/NBNS-Studio/PM670/DRUMSFAIR2.wav

Custom TC network 1 :
http://pagesperso-orange.fr/NBNS-Studio/PM670/DRUMSCUSTOM1.wav

Custom TC network2 :
http://pagesperso-orange.fr/NBNS-Studio/PM670/DRUMSCUSTOM2.wav



Thanks to SaMpLeGoD for the BOM with Banzai codes :
http://pagesperso-orange.fr/NBNS-Studio/PM670/BOM_for_Side_Chain_Amp_Boost_for_PM670.doc


Thanks to Moby for the wiring guide ! It can be found here :
http://pagesperso-orange.fr/NBNS-Studio/PM670/PoorMan+SCAB-WiringGuide-R1.pdf


Or you can read that  ::):

Fill the board  ;D !!!

On the PSU board set RV1 and RV2 to have +17V and -17V.
Connect those +-17 to my board.

If you start filling the PM board, don't solder D1, D2, D3, D4, C4, R16 and R18. Put 2 wire links between C4 pads and R18 pads.
If they're already soldered, solder a wire link between the C4 pins and between R18 pins. I can't honestly say that's it is a good idea to dissolder C4 (even if I did) as it can endomage the PCB if not correctly done. Cut D1, D2, D3, D4 on the middle of the glass tube. Then keeping hot the pin solder, remove the half diodes. This is my tip to remove these diodes easily, without staying hot a too long time on the board.

TR4 output (secondary) goes directly on the SCAB board.

The SCAB "to attack" connector will be connected to the "attack" connector of the PM board.
The SCAB "attack" connector is the 10K pot of Analags network design.
The SCAB "MODEA-L or R" + MODEB-L or R" is where you connect the DPDT switch to change the MODE from "Analag's network" to "Your a la Fairchild network". There's unfortunately a 1 dB overall gain raise when not in "Analag's mode". There are 3 pads added to solve this but we will talk about this later.

Put the SCAB in "analag's mode", set RVx01 so the SCAB "to attack" connector pin to pin reads 0V DC on multimeter.

If you solder a 2uF in Cx03 place, you've got the Fairchild POS 2 setting when switched in "a la Fairchild mode".

Here you are, ready to experiment !

Play, have fun and feel free to post here...

EDIT : Read my "pimping my own pimp" post on second page to have a really well working mod !
 
Lolo, it will be nice if you can do the wring diagram as Volker did for PM. Or you can add SCAB PCB into existing one . I figure how it has to be connected but I'm sure that there will be a lot of questions about  ;)
 
I'd like to konw it it's possible to use the +17V on the PSU PCB for the SCAmp Booster and drop the same voltage via a simple resistor for let's say 12V relais? Is there enough juice for the opamps and four relays?

thanks!
christoph
 
crisotop said:
I'd like to konw it it's possible to use the +17V on the PSU PCB for the SCAmp Booster and drop the same voltage via a simple resistor for let's say 12V relais? Is there enough juice for the opamps and four relays?

thanks!
christoph
On the board there's a 7812 to provide the 12V for the relays, lighting... with same KK connector than on the PSU board. All you'll have to do is to plug relays on the SCAB board... Just one warning, try to stay under 500mA of total consumption for lighting and relays. I would suggest to use maximum led lighting (where it is possible SIFAM meters, ON light...)  instead of bulb lighting because leds doesn't eat a lot of current.

Moby said:
Lolo, it will be nice if you can do the wring diagram as Volker did for PM. Or you can add SCAB PCB into existing one . I figure how it has to be connected but I'm sure that there will be a lot of questions about  ;)
Moby you're perfectly right !!! I was thinking to do this... As I won't be connected to the web during the week-end, I will try to do this... More simple and quick !

DON'T BE AFRAID THIS MOD IS TOTALLY REVERSIBLE IF YOU DON'T LIKE IT  ::). This was a part of the hard job !!!
 
Moby you're perfectly right !!! I was thinking to do this... As I won't be connected to the web during the week-end, I will try to do this... More simple and quick !
If you need some help I'm here  :)
 
On the board there's a 7812 to provide the 12V for the relays, lighting... with same KK connector than on the PSU board. All you'll have to do is to plug relays on the SCAB board... Just one warning, try to stay under 500mA of total consumption for lighting and relays. I would suggest to use maximum led lighting (where it is possible SIFAM meters, ON light...)  instead of bulb lighting because leds doesn't eat a lot of current.

Genius, should have had a closer look before posting - as always ;)

thanks for clearing this up!
Christoph
 
Do we need proper 'big' heatsinks (similar to the ones used for Q1 on the pm boards) for the 7812 and the TIP transistors, or will something smaller do?

cheers
christoph
 
I would suggest to fix the board on the case INSULATED. This is a simple way to cool everything for the lowest cost possible. If not possible to do that, 7812 can get hot (depend of current consumption of lighting and relays). A heatsink with the same °C/W than the one used for the 317 in the PSU board will do.
But I think that the best is to fix the TO220 to the case...
 
SCAB WiringGuide is ready  ;D http://www.mediafire.com/file/yfwfyfqv0ww/PoorMan+SCAB-WiringGuide.pdf
 
Moby said:
SCAB WiringGuide is ready  ;D http://www.mediafire.com/file/yfwfyfqv0ww/PoorMan+SCAB-WiringGuide.pdf

It doesn't download on that site.  Is there something I"m missing?  (I'm on OSX, maybe that's why?)
 
Moby said:
Don't know... works for me..  :-\
edit:works under os x too (me)

Yes, but you're probably logged in as the owner of that document/account.  Do I have to start an account to download it?
 
don't have an idea... but I don't know where to upload :-\ BTW, I didn't type any pass under OS x....
 
allright, here's another one: As far as I've studied the schematic and circuit board, it should be possible to use a 6pos 2pole switch for having analags original 10k pot on the first deck as 6pos á 2k switch and my deisred Fairchild-inspired RC combo on the second deck with wathever cap/resistor values I want, since both circuits are fully independent - did I get this right?

Thanks in advance,
Christoph
 
crisotop said:
allright, here's another one: As far as I've studied the schematic and circuit board, it should be possible to use a 6pos 2pole switch for having analags original 10k pot on the first deck as 6pos á 2k switch and my deisred Fairchild-inspired RC combo on the second deck with wathever cap/resistor values I want, since both circuits are fully independent - did I get this right?

Thanks in advance,
Christoph
Yes, you're perfectly right !
 
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