SSL 4000 EQ

[Ptownkid]

Do it! I dare ya! 

 

[signalflow]

Prototypes came in.  It'll probably be mid January to beginning of February before I have one up and running due to the holidays and the never ending spirit of Christmas that is my wallet.

http://www.groupdiy.com/gallery/0/11898-081211095718.jpeg

-Casey

 

[atticmike]

why do you do this to us?

I'm already freakin pumped to start this build

 

[pedroplanet]

It's a hit!

 

[atticmike]

Prototypes came in.  It'll probably be mid January to beginning of February before I have one up and running due to the holidays and the never ending spirit of Christmas that is my wallet.

http://www.groupdiy.com/gallery/0/11898-081211095718.jpeg

-Casey

hey mate,

Any progress yet?

 

[signalflow]

Still have to order pots from colin @audio maintenance.  Rest of the parts should be at my place tomorrow.

I'll keep everyone updated when there are updates.

-Casey

 

[signalflow]

Well now I have an update.  Parts arrived today. kinda exciting. Only thing left is to check voltages, install chips and mount the pots from Colin once I order them(one thing at a time).

Should have this passing audio mid February.

-Casey

 

[spase]

we are waiting for the final product.its looks Great!

 

[atticmike]

Well now I have an update.  Parts arrived today. kinda exciting. Only thing left is to check voltages, install chips and mount the pots from Colin once I order them(one thing at a time).

Should have this passing audio mid February.

-Casey

Great man!

Got a question about the eq's features. If it was based on the black knob, weren't there supposed to be 10 knobs?

 

[signalflow]

If you read further back in the thread you will see that the gain and freq select arebeing done on concentric pots due to space issues.  The pots mounted right now are the Q sweep contols. Take a closer look at the footprints left un-populated and you will see 4 3 deck pots, these are the concentic pots.

-Casey

 

[Ethan]

Sorry guys, I had to delete posts after #50.
There must have been a strange server hiccup that caused the message data to become corrupt and would cause this topic to hang.
It should be OK now, carry on...

 

[signalflow]

Thanks Ethan,

OK, so I've had this thing up and "running" now for about a month and have had some folks at different studio's here say that it sounds awesome.

When I say "running", I'm having 2 minor issues both to do with the bypass.

1)  Relay's are popping when switching in the bypass.  Could be the switch I'm not sure, but in case it's not what could be causing this?  I have caps and diodes on the rails going to both relay's but still have the pop.  Any thoughts?  I used the same relay setup that's in the SB4000 and i haven't heard anyone having problems with it.

2) When switching into bypass I lose about 5-6db of signal. even when the eq is flat this is happening.  Kinda puzzling to me.

Now there were some errors to the layout one being that when in bypass the phase is flipped(wasn't paying close enough attention when drawing the schematic and didn't catch it till it was too late) I wouldn't think this would cause my volume drop but at this point I'm eager to be educated.

Here are some Pic's

http://sphotos.xx.fbcdn.net/hphotos-ash3/553680_147633892030042_2027937207_n.jpg
http://a4.sphotos.ak.fbcdn.net/hphotos-ak-ash3/544511_147634002030031_100003502971171_176809_2121204754_n.jpg
http://sphotos.xx.fbcdn.net/hphotos-ash4/292153_176288519164579_100003502971171_256181_1635711567_n.jpg

Here is the original schematic
http://www.ka-electronics.com/images/SSL/ssl_82E02.pdf

Here is my updated schematic
http://www.groupdiy.com/gallery/0/11898-200512174752.png

If there are any glaring errors let me know.  Like I said It sounds pretty sweet just needs to figure out the two problems above.

Also, I just left the Q adjustment pots at half way.  Is there some method to setting these or is it just a taste thing?

Thanks,

-Casey

 

[braeden]

Very nice, can't wait to build a few of these once everything has been ironed out!

Good luck!

 

[wolfgang]

1)  Relay's are popping when switching in the bypass.  Could be the switch I'm not sure, but in case it's not what could be causing this?  I have caps and diodes on the rails going to both relay's but still have the pop.  Any thoughts?  I used the same relay setup that's in the SB4000 and i haven't heard anyone having problems with it.

2) When switching into bypass I lose about 5-6db of signal. even when the eq is flat this is happening.  Kinda puzzling to me.

Maybe its some DC on the Audio. Looking at your Schematic you have no DC-Blocking Caps on the Input. Thats good for the THAT-Input but maybe there is some DC on the gear before your EQ. You could try out two caps with resistors to Ground in front of your EQ and hear if t helps!

And for the Level Drop: I havent looked if you need 6dB Gain after your EQ- Circuit????? Input is THAT 1240 which is unity-Gain and output is THAT1646 which has 6dB Gain. May this is the answer??

regards,
Wolfgang

 

[signalflow]

And for the Level Drop: I havent looked if you need 6dB Gain after your EQ- Circuit????? Input is THAT 1240 which is unity-Gain and output is THAT1646 which has 6dB Gain. May this is the answer??

regards,
Wolfgang

sorry Schematic says 1240 but it's a 1246 in the socket, which should give a 6db drop and the 1646 gives a 6db boost on the out.  It seems that there is more gain coming from the circuit itself, just don't know where to start looking. 

Thanks for the cap suggestion. Am I correct in thinking your talking about a c-r-c board like the ones that are used for the gssl that rochey makes?

**EDIT** Just remembered that it pops even without anything plugged into the input.

-Casey

 

[wolfgang]

No - i wasnt thinking of CRCRC - Board.

I thought off putting a Cap in Series ( with resistor to ground) in each of the 2 input signals right before the output-switching relay to remove possible DC-Offset from the Input-Signal! Also i would remove the Input Switching relay - there could be another issue! The input -pins from the 1246 are floating if it is in bypass-mode. Just switch the Signal on the output between wet and dry.(with the caps i suggested)

regards
Wolfgang

 

[signalflow]

Ahhhh gotchya.  I'll try your suggestions out and see what happens.  I'm just puzzled why other projects that use this same set-up don't seem to have the same problem with the popping.

Thanks Wolfgang!

If anyone has any Ideas as to why the signal drops when the eq is bypassed I'm all ears! Or I guess I should say why the EQ is boosting the level when it's in use.

-Casey

 

[abechap024]

I think, this would be a fun project to build!

 

[signalflow]

I think, this would be a fun project to build!

Even with the problems I'm having it was very fun & rewarding to have it fire up the first time and pass some sweet sounding audio.

Just gotta get rid of these 2 problems(BUMP)and I'll be glad to turn it over to everyone else.

-Casey

 

[wolfgang]

Any news on your 2 problems?

regards,
Wolfgang