SB4000 Support Thread

[sr1200]

Just wanted to drop a line... I used one of mine last night to smack the taste out of some drum room mics... damn this thing is sweet!!!  Usually reserve the other for mix bus duties, but haven't gotten to that point yet... still tracking!

 

[band_master]

hey guys,
just an update...i tried the unit out on some program material tonight. ran a pair of L/R drum overheads through it. It seems to be acting like a compressor, make-up gain and threshold are working. meters are lighting up in the generally correct way. still not sure how to proceed with calibration as I am only able to adjust to 1.4v at TP11 and TP12 vs. 2.9v at TP8 and TP10. Could the quad VCAs be a factor here as voltages are off by around a 1:2 ratio? or could it be b/c my multimeter does not have true rms?

BD

EDIT: The voltages above were taken with a 1Khz sine wave at -10db set to RMS mode in pro tools.

P.S. the unit sounds really good so far with an excellent signal to noise ratio. looking forward to getting it all dialed-in and racked!

 

[mica]

Im nearly finished with mine based 100% on the BOM, bought from Mouser..

A couple of newbie questions:

1. The Jumpers 1-6 in the R+L VCA area.. should I "jump" those or some of them? Cant seem to find it in the guide.

2. R111, when should I use that? I have the VU from Hairball Audio: (http://hairballaudio.com/shop/product_info.php?cPath=25&products_id=61)

3. The jumper on the control board next to the bargraph - JMP7.. Should I "jump" that?

4. On the back of the main PCB, it says for CnB: CUT ME! Im not shure about CnB.. When should they be cut?

5. J19 3pin (close to center of mail pcb)? What is that for?

/Michael

 

[wave]

Im nearly finished with mine based 100% on the BOM, bought from Mouser..

A couple of newbie questions:

1. The Jumpers 1-6 in the R+L VCA area.. should I "jump" those or some of them? Cant seem to find it in the guide.

2. R111, when should I use that? I have the VU from Hairball Audio: (http://hairballaudio.com/shop/product_info.php?cPath=25&products_id=61)

3. The jumper on the control board next to the bargraph - JMP7.. Should I "jump" that?

4. On the back of the main PCB, it says for CnB: CUT ME! Im not shure about CnB.. When should they be cut?

5. J19 3pin (close to center of mail pcb)? What is that for?

/Michael

1. There's a chart on the schematic that tells you which jumpers to populate depending on what VCA you use
2. IIRC you don't put that resistor in for that type of meter
3. Yes put that in
4. Leave that alone. That's for an optional Crush&Blend circuit
5. Not sure what you're referring to post a pic maybe?

Dave

 

[mica]

Thank you!

A pic of J19:

Im using THAT2181A for L+R VCAs, so i guess i can just go with the values on the PCB all the way? (Populate JMP1+JMP4)

(The PCB is rev. 4)

/Michael

 

[wave]

If I recall, I didn't put anything there as I couldn't find it on the partslist.
JMP1 and 4 is correct for 2181A.

You're in the home stretch!

Dave

 

[mica]

Great!

I ran into another issue..

My trafo has 4 colored wires, and 2 yellow: 2x18V (gn-rt / bn-bl) - unlike the ones i have seen in the documentation, and in this forum.

My powerswitch is mouted: I on top, and O in bottom.
How shuld i connect the power to the powerswitch and to the trafo? (We have 230V here in Denmark)

 

[tom f]

Hello,
while building the SB 4000 I have one question.
Which VU- meter do you have installed and where did you get it
(Im in Germany) ?

Thanks a lot
Tom

 

[wave]

Hello,
while building the SB 4000 I have one question.
Which VU- meter do you have installed and where did you get it
(Im in Germany) ?

Thanks a lot
Tom

Tom,
I bought this one from ptownkid

http://diypartssupply.com/index.php?main_page=product_info&cPath=3&products_id=29&zenid=k88h78li6cl88ame1iv5s2n0s3

Dave

 

[wave]

Great!

I ran into another issue..

My trafo has 4 colored wires, and 2 yellow: 2x18V (gn-rt / bn-bl) - unlike the ones i have seen in the documentation, and in this forum.

My powerswitch is mouted: I on top, and O in bottom.
How shuld i connect the power to the powerswitch and to the trafo? (We have 230V here in Denmark)

Can you send me a link to the datasheet for the trafo?

Dave

 

[miketeachesclass]

I'm populating my SB4000, and noticed that there are a few parts missing from the BOM.

For example, C12 and C13 are not on the BOM.  the Silkscreen says 150nf, and the schematic says "TBD" for those values. 

Is the silkscreen correct?  Has anyone else noticed this?  Are there any other parts that are missing from the BOM?

Thanks,
Mike

 

[tom f]

Hi Dave,
thanks for the information.
Tom

 

[mica]

Great!

I ran into another issue..

My trafo has 4 colored wires, and 2 yellow: 2x18V (gn-rt / bn-bl) - unlike the ones i have seen in the documentation, and in this forum.

My powerswitch is mouted: I on top, and O in bottom.
How shuld i connect the power to the powerswitch and to the trafo? (We have 230V here in Denmark)

Can you send me a link to the datasheet for the trafo?

Dave

It says:Talema TRT30218 so i guess this one: http://www.banzaimusic.com/Talema-TRT30218.html

/Michael

 

[wave]

Michael,
I guess you would hook one of the yellow wires to the Neutral terminal of the power inlet. Run another wire from the Live terminal of the power inlet to the bottom pin of the power switch. Hook up the other yellow wire to the center pin of the power switch. Put shrink tube over the top pin of the power switch (there's no connection to the top pin)

Dave

 

[band_master]

so i discovered that the excel version of the bom has the wrong mouser part number 3266W-1-102LF for VR5,VR7,VR8, and VR10.

it is a 1K trimmer instead of a 10K...i think the actual mouser part number should be 652-3266W-1-103LF? we'll see if that works.

 

[mica]

Hi Dave.. thx a million for your responses.

Is this what you mean:

 

[wave]

That's correct Michael!

Dave

 

[miketeachesclass]

so i discovered that the excel version of the bom has the wrong mouser part number 3266W-1-102LF for VR5,VR7,VR8, and VR10.

it is a 1K trimmer instead of a 10K...i think the actual mouser part number should be 652-3266W-1-103LF? we'll see if that works.

You may be working from an old version of the BOM?  I just checked the excel BOM, and the part number listed is:


652-3306F-1-103 

Which is the 10k trimpot.

Mike

 

[miketeachesclass]

I spent some time today going through the serpent BOM and the excel bom put together by  azone.

The serpent bom doesn't include:
C12, C13, C129, C139:  150nf mouser PN:  505-mks20.15/63/5
C117, C131, C138:  220nf mouser PN:  505-mks2.22/63/5t

The excel BOM doesn't include:
Ribbon cable connector:  mouser PN:  653-XG4M-2030-T

It's worth mentioning that the excel bom includes part numbers for various upgrades and options not included on the serpent bom, such as capacitors in the "boxy" package type, the optional trimpots/etc. In my opinion, it would be good to go through both before ordering your parts.

Mike

 

[miketeachesclass]

Regarding the quad vca:

The quad vca calls for the 2181B. Do we still need to make the resistor changes on the schematic for the 2181B (these changes weren't originally intended for the quad vca) , or do the changes listed on the quad vca bom take care of ALL necessary changes?

Thanks,
Mike