SB4000 Support Thread

[jandoste]

and I will try the semi LM7912

Yes it was ST ! and the Psu works now !

Don't use ST LM7912 !
Don't use ST LM7912 !
Don't use ST LM7912 !
Don't use ST LM7912 !

Cheers,

 

[jandoste]

Hi Mike,
I gor two questions,
Firts I used the same switches and I would like to be sure the wires connection ? how ?

and the second question is for the the VCA's JMPs?

Thanks,

 

[jandoste]

Hi Mike,
I gor two questions,
Firts I used the same switches and I would like to be sure the wires connection ? how ?

and the second question is for the the VCA's JMPs?

Thanks,

yep ! any advice ?
Thanks,

 

[ruckus328]

Umit, it's just a SPDT switch like any other.  2 of the pins are for the LED.  They should all be marked on the switch, otherwise look on the datasheet for which pins are what, I don't know off the top of my head.  The board connectors are all labeled, schematic and wiring chart in the build manual show very clearly what goes where.

VCA Jumpers - In giant bold text on the board is says refer to the schematic.  There's a table on the schematic that tells you which ones to install, it depends on the VCA's you're using.

 

[ruckus328]

Does a 67x34mm toroidal transformer will fit ? I'm not sure about it so I prefer to check...
This is this one :
http://www.electronique-diffusion.fr/product_info.php?products_id=1077

Depends on the height of your enclosure.  Electrically it is fine.

 

[jandoste]

Umit, it's just a SPDT switch like any other.  2 of the pins are for the LED.  They should all be marked on the switch, otherwise look on the datasheet for which pins are what, I don't know off the top of my head.  The board connectors are all labeled, schematic and wiring chart in the build manual show very clearly what goes where.

VCA Jumpers - In giant bold text on the board is says refer to the schematic.  There's a table on the schematic that tells you which ones to install, it depends on the VCA's you're using.

Thanks Mike,

 

[ruckus328]

No problem, just to add - the picture of one of the illuminated switches is top left side of the schematic, the VCA table is below that.

 

[Songguy]

Hi all,
Anyone have the back panel cut out measurements on hand. I need to send them to John at par metal so can get my project going.

Many thanks,
Chris

 

[jandoste]

Hi All,
I have a problem with the analog VU Meter. it does not move. Do you have an idea? I checked all wires connection and all is right !
Thanks,

 

[sheadstedford]

Got a quik impedance question!
I got the tube stage at input unbalncing it at 10kohm going into the sb4000, thats 600ohm i understand.
Do i definitly need a 10k to 600ohm tranny or can i still use it stright wired from tube out to sb4000 input connector?
Will this damage the sb4000 in any way?

 

[ruckus328]

Hi all,
Anyone have the back panel cut out measurements on hand. I need to send them to John at par metal so can get my project going.

Many thanks,
Chris

Chris, there's no set rear panel dimensions, it's wherever you want to put your connectors.  I just eyed it up with whatever looked good, think I put my xlr spacing at 2" or something like that.

 

[ruckus328]

Hi All,
I have a problem with the analog VU Meter. it does not move. Do you have an idea? I checked all wires connection and all is right !
Thanks,

Do you have makeup gain?

Is the unit compressing/threshold knob working?

If answer is yes to both questions than narrows it down to only a couple parts where problem could be.

+ On your meter should go to J7 Pin 1
- On your meter should go to J7 Pin 2

Did you install R111 (330R)?  If you're using a 1mA meter (you probably are) it should not be installed.

Have you tried adjusting VR17 (5K Pot)?

 

[ruckus328]

Got a quik impedance question!
I got the tube stage at input unbalncing it at 10kohm going into the sb4000, thats 600ohm i understand.
Do i definitly need a 10k to 600ohm tranny or can i still use it stright wired from tube out to sb4000 input connector?
Will this damage the sb4000 in any way?

Input impedance of SB4000 is 22K.

 

[sheadstedford]

Thanks!!

Ive hooked everything up and it sounds awsome!

 

[jandoste]

Do you have makeup gain?

No, I have no sound ! ???

Is the unit compressing/threshold knob working?

No, they are not...

Did you install R111 (330R)?  If you're using a 1mA meter (you probably are) it should not be installed.

Yes, I'm... I used 1mA from Hairball...

Have you tried adjusting VR17 (5K Pot)?

I tried but nothing change with it.

Thanks,

 

[sheadstedford]

So for the the 1ma hairball meter i should NOT install the 330r resistor?
Even though there is a little box for it markedon pcb?

 

[ruckus328]

No, I have no sound ! ???

One thing at a time.  If you have no sound then why would you expect anything else to be working ??? 

So you're saying the unit isn't passing audio?

 

[ruckus328]

So for the the 1ma hairball meter i should NOT install the 330r resistor?
Even though there is a little box for it markedon pcb?

Correct, The little box says for 100uA meter only.

 

[jandoste]

No, I have no sound ! ???

One thing at a time.  If you have no sound then why would you expect anything else to be working ???  

So you're saying the unit isn't passing audio?

Yes, but I see the signal with Led METER !

 

[ruckus328]

Umit:

1) Your ribbon cable is backwards.  You have pin 1 on the main board going to pin 20 control board.  It needs to be corrected before we can continue.  Please verify the rest of you wiring polarities are correct.  Pin 1 is labeled on all connectors.

2) When in bypass does the unit pass audio?

3) I see all of the bargraph LED's are illuminated.  If you turn down the volume of your input signal, do the lights start to turn off?