GSSL HELP THREAD!!!

[React]

Thanks for the answers Harpo

im from Sweden and i think i have to break both in my country. We have 230V 50Hz in our outlets here.

Then about the bypass when i was saying "true bypass" i meant bypassing both as in making sure the "makup gain" is also bypassed. I really would like to have some kind of light to display the status of the bypass but i have nere buildt anything with relais before in my life. I have no idea how they work, what kind of powersupply, how to connect. Read a lot about them n the internet, but im still a bit scared of them.

Relais has to be fed with some sort of current, and is it when current is "on" it switches and stays in place? they need DC-current to work right? and if i use a relais i probably need to build an own powersupply for it.

So what it sounds like is that i need to build another powersupply to support the bulb in the meter and a relais that is activated by my bypassswitch with 3 switching poles, where 2 are the bypasses and the 3 is maybe an led that ALSO needs power from somewhere to a reistor to 0V

 

[ptron]

is it going to make a difference in sound or performance that my whole lot of .1uF be 100V instead of 63V?

(i know i asked the same (ish) in the SSC help thread but i want to know regarding the audio path if its going to be as harmless)


EDIT: and for electrolytics is it better low leakage or low impedance?

thanks a lot!  ;D

 

[mac]

.1uF be 100V instead of 63V?

absolutely no difference, as long as they fit, and are of the same quality.....

Mac

 

[ptron]

safe! thanks

 

[ej_whyte]

Hi,

Got a problem with my SSL.

I've just finished building (almost, I don't have the NE5532s yet, should arrive tomorrow, but I don't think this is to do with the problem, as the problem is a difference between the two channels, which are both without NE5532) and was testing it out a bit.

There seems to be a problem between the two channels, one of them seems to be working fine, whilst the other has a very low output, it hardly registers on the meters when put through full gain on a pre. Its definitely not the VCAs, as I've swapped them over and there was no change, likewise with the NE5534s.

Does anyone have any ideas as to what this is?

Where should i be poking my multimeter?

Thanks

 

[frazzman]

Hi guys,
I'm trying to work out an LED meter PCB to use for a GSSL, now that the PICO PCB can't be obtained i'm trying to find an alternate that does the same job, anyone think this will fit the bill?:

http://cgi.ebay.com/10-LED-Bargraph-display-Meter-PCB-LM3914-5-6-multi-use-/330377869958?pt=LH_DefaultDomain_2&hash=item4cec0e3a86

It uses the same IC but it doesn't have a TL071 chip, I think the GSSL needs the voltage inverted when tapping it frm the mainboard..?

Any ideas?

 

[Harpo]

I've just finished building (almost, I don't have the NE5532s yet, should arrive tomorrow, but I don't think this is to do with the problem, as the problem is a difference between the two channels, which are both without NE5532) and was testing it out a bit.

I've just finished building a racing car (almost, I don't have the breaks in yet, should arrive tomorrow, but I think I'll give it a try at full speed just now ... ;D

There seems to be a problem between the two channels, one of them seems to be working fine, whilst the other has a very low output,...

Without the 5532s both channels will not be working fine. The one with the higher output has the higher off ideal value 10k resistors or is connecting to an input with messed up CMRR.

 

[Harpo]

Hi guys,
I'm trying to work out an LED meter PCB to use for a GSSL, now that the PICO PCB can't be obtained i'm trying to find an alternate that does the same job, anyone think this will fit the bill?:

http://cgi.ebay.com/10-LED-Bargraph-display-Meter-PCB-LM3914-5-6-multi-use-/330377869958?pt=LH_DefaultDomain_2&hash=item4cec0e3a86

It uses the same IC but it doesn't have a TL071 chip, I think the GSSL needs the voltage inverted when tapping it frm the mainboard..?

Any ideas?

Should do it. Leave out D2 and C1.
Just put an inverting opamp on a piece of perfboard or with flying leads in front of it, could be a TL071.
The tricky part with this LM3914 meter is the 120mA supply and connection to 0V for current return not affecting audio.

 

[ej_whyte]

I've just finished building (almost, I don't have the NE5532s yet, should arrive tomorrow, but I don't think this is to do with the problem, as the problem is a difference between the two channels, which are both without NE5532) and was testing it out a bit.

I've just finished building a racing car (almost, I don't have the breaks in yet, should arrive tomorrow, but I think I'll give it a try at full speed just now ... ;D

There seems to be a problem between the two channels, one of them seems to be working fine, whilst the other has a very low output,...

Without the 5532s both channels will not be working fine. The one with the higher output has the higher off ideal value 10k resistors or is connecting to an input with messed up CMRR.

OK thanks, yeh i know it wasn't ideal, just couldn't wait to give it a go, they're here now anyway  

I still have the same problem though, one channel has a very high output (clips the converters even when going in with no gain), however i think possibly my makeup gain isn't working properly and may be stuck at max (I'm not sure about this, I'm gona make a pad quickly to try and check, because maybe the output is so high that even with no makeup gain it still clips the A/D). SO yep either stuck at max or extremely high output.

The other channel however, totally different story! The output is hardly above the noise floor, have to turn up the pre all the way just to get the first led on the meter blinking.

*Sigh*  :-\

 

[Harpo]

I still have the same problem though, one channel has a very high output (clips the converters even when going in with no gain), however i think possibly my makeup gain isn't working properly and may be stuck at max (I'm not sure about this, I'm gona make a pad quickly to try and check, because maybe the output is so high that even with no makeup gain it still clips the A/D). SO yep either stuck at max or extremely high output.

More unlikeley makeup gain related.
Keep your A/D converter disconnected until the gssl is working properly or you intentionally want to blow up your converters input stages.
Double check resistor values.
All needed resistors in place, or are the maybe missing ones supposed to arrive tomorrow as well... (sorry, couldn't resist);D
This reply some pages back http://www.groupdiy.com/index.php?topic=47.msg483540#msg483540 might help you a little.

The other channel however, totally different story! The output is hardly above the noise floor, have to turn up the pre all the way just to get the first led on the meter blinking.

Might be a short or a broken or missing part/connection.
Good luck

 

[ptron]

just couple of topic related questions   (i think)

1- can i use 2181B for sidechain VCA and 2181A for audio and is the same as if i was using 3 x 2181A ? (or 4 with turbo).. (i mean in performance of the compressor will be the same?)

2- in "calibration using THAT 2181", pin 5 and 3 of sidechain vca has a 10k removed from between their leggs ;D . i should also remove it from the turbo board??  (beneath 470R)

and

3- to switch turbo/gssl mode,  i need dpdt latching toggle sw?

cheers!

 

[ej_whyte]

I still have the same problem though, one channel has a very high output (clips the converters even when going in with no gain), however i think possibly my makeup gain isn't working properly and may be stuck at max (I'm not sure about this, I'm gona make a pad quickly to try and check, because maybe the output is so high that even with no makeup gain it still clips the A/D). SO yep either stuck at max or extremely high output.

More unlikeley makeup gain related.
Keep your A/D converter disconnected until the gssl is working properly or you intentionally want to blow up your converters input stages.
Double check resistor values.
All needed resistors in place, or are the maybe missing ones supposed to arrive tomorrow as well... (sorry, couldn't resist);D
This reply some pages back http://www.groupdiy.com/index.php?topic=47.msg483540#msg483540 might help you a little.

The other channel however, totally different story! The output is hardly above the noise floor, have to turn up the pre all the way just to get the first led on the meter blinking.

Might be a short or a broken or missing part/connection.
Good luck

Merry Xmas everyone!

Anyway, had a bit of a break, but now I'm back on to trying to fix this ssl. So I have just rechecked all the voltages, and I found that the left channel NE5532 has 13.6v on output 1, and -13.6v on output 2, whilst the right NE5532 has 0v on both, however they both have the same voltages on all the other pins, except pin 6 on the left channel (2in-), which is showing ~0.7v. Heres a little pic I made to make it a bit easier to understand.

Do i have a duff IC or is it to do with other components?

Thanks

[EDIT] I just found that when i take the IC out and check them, both pin 2 (1in-) and pin 6 (2in-) show 0.7v, as well as the outputs. [EDIT]

 

[Harpo]

13.6v on output 1, and -13.6v on output 2, whilst the right NE5532 has 0v on both, however they both have the same voltages on all the other pins, except pin 6 on the left channel (2in-), which is showing ~0.7v. Heres a little pic I made to make it a bit easier to understand.

Do i have a duff IC or is it to do with other components?
[EDIT] I just found that when i take the IC out and check them, both pin 2 (1in-) and pin 6 (2in-) show 0.7v, as well as the outputs. [EDIT]

Double check for shorts (using a magnifying glass).
Whatever voltage is on output1 is a followup from output2. Pull out the left ch audio VCA and bypass this VCA with a wire bridge pin1/8. Check NE5532 pin7 for about 0V with no signal present or half signal voltage with signal present again. If its still this -13.6V, most likeley the opamp is broken, else the VCA might be blown.

 

[braeden]

Hey everyone,
I don't suppose anyone knows where to get the IC holders for the THAT 2180 VCA's. If I'm not mistaken they're called SIP IC holders?
A part number would be appreciated, I can't seem to find them anywhere.

I suppose the advantage of the IC holder is that I can mix and match VCA's whenever I want to, but other than that I can just solder the terminals straight to the PCB right?

If worst comes to worst I'll just solder them, I just hope heat is an issue and I don't cook my VCA's (which cost around $30 in Australia, what a load of...)

I've also been taking some nice high-res photos of the build so if it all pans out and works okay I'll be sure to post them

Thanks guys

 

[tzman]

Hey everyone,
I don't suppose anyone knows where to get the IC holders for the THAT 2180 VCA's. If I'm not mistaken they're called SIP IC holders?
A part number would be appreciated, I can't seem to find them anywhere.

I suppose the advantage of the IC holder is that I can mix and match VCA's whenever I want to, but other than that I can just solder the terminals straight to the PCB right?

If worst comes to worst I'll just solder them, I just hope heat is an issue and I don't cook my VCA's (which cost around $30 in Australia, what a load of...)

I've also been taking some nice high-res photos of the build so if it all pans out and works okay I'll be sure to post them

Thanks guys

Just buy something like this http://www.banzaimusic.com/SIL-64-pins.html.
You can easily cut them to length with a razorblade or Xacto knife.

 

[Harpo]

.. or cut a 16pin DIL socket in half ..

 

[braeden]

.. or cut a 16pin DIL socket in half ..

Yeah I was thinking about doing this but wasn't sure if it was the proper thing to do... I'm pretty picky with things like that and I like things to be professional rather than a hackjob.

Thanks for the advice, appreciate it

 

[ej_whyte]

13.6v on output 1, and -13.6v on output 2, whilst the right NE5532 has 0v on both, however they both have the same voltages on all the other pins, except pin 6 on the left channel (2in-), which is showing ~0.7v. Heres a little pic I made to make it a bit easier to understand.

Do i have a duff IC or is it to do with other components?
[EDIT] I just found that when i take the IC out and check them, both pin 2 (1in-) and pin 6 (2in-) show 0.7v, as well as the outputs. [EDIT]

Double check for shorts (using a magnifying glass).
Whatever voltage is on output1 is a followup from output2. Pull out the left ch audio VCA and bypass this VCA with a wire bridge pin1/8. Check NE5532 pin7 for about 0V with no signal present or half signal voltage with signal present again. If its still this -13.6V, most likeley the opamp is broken, else the VCA might be blown.

Thanks for all your help Harpo, this is my first build and I was beginning to think maybe I wasn't cut out to be a DIYer. Anyway, I have fixed my problem  ;D  I've just got to add my turbo board and then its all finished.

It was actually just three little things wrong with it, but they just added up to utter frustration!
1. I found a tiny short between the left + and - on the left input connector.
2. The left VCA was fried, distorting all over the place. I've taken the 2181A out of the sidechain and put it in the left VCA instead, and used the 2180B that came with my turbo board in the sidechain for now (thanks PtownKid for that). So just need 1 new 2180B for the turbo now.
3. I had the makeup gain wired to the wrong pole on the bypass switch, so makeup was on when the compressor was bypassed, and off when it was on  :

So just got to wire the connectors on the turbo and its all done, its not gone toooo bad for my first DIY  I'll be posting some pics soon, I know everyone is probably bored of seeing GSSLs, but mine has a pretty unique look, which I haven't seen anywhere else, so why not eh?!

Cheers,
-Elliott

 

[California Road]

Hey Guys,

I am wondering about a substitution for the 25 .1uf 63v film caps on the BOM.  They are out of stock at Mouser and won't be in until like May!

Will these work in there place?

http://search.digikey.com/scripts/DkSearch/dksus.dll?lang=en&site=US&WT.z_homepage_link=hp_go_button&KeyWords=ef1104-nd

If not, anyone has any suggestions.

Thanks,

Josh

 

[ptron]

would these work?

Mouser #: 667-ECQ-V1H104JL
Mfr. #: ECQ-V1H104JL
Desc.: Polyester Film Capacitors .1uF 50V 5%