Dr-Mbogo
Member
even with a 1kHz sine signal the needle of the meter has a dependency on the release pot. the slower the release time - the more gain reduction is shown.
All things G1176 - the new "repost" thread.
- Thread starter orson whitfield
- Start date
Help Support GroupDIY Audio Forum:
pablobolche
Well-known member
I am going to build a Dual 1176 Mnats Rev J. I sourced a double meter from a Studer b77. Would these work, what should take extra care with?? any help or link to relevant info is appreciated.
Thank You
Thank You
Dr-Mbogo said:
Could be leakage in the FD333-diodes, or poor isolation somewhere (pot to chassis?). The timing/threstold/bias part of the circuit is very high-impedance and "floating" on top of the Qbias voltage.
The Studer meters most probably won't be real ac-reading VU-meters. Refer to earlier in this thread for how to ensure the right meter.
Jakob E.
hi there,
this is about my dual-1176 rev.j by jakob. after all, i'm very happy to be into diy again- apart from soldering cables every now and then
been reading a lot on this board and have a question... to contribute at least something, i link some pictures (blurry handy fotos, but...) of my dual1176 living in the ugly body of an behringer t-19xx. the piece is generally working and i use it often for my mixes. the enclosure is not so bad: basic drillings and the input/output-jack section that i just used as it was, same with the powerswitch. had to use different knobs- but i think they fit well. another extra are the lundahls, 1539 instead of 1540. therefore the ugly perfboards to get the different wirings connected to the main pcb.
the thing with the behringer meters: i just used the built in ones- at least they showed some activity after checking with different resistors. i made the first pair to show gainreduction, the second pair shows output always. (hey can your 1176 do that? 8) ) lacking a good idea for the frontplate lettering i'll probably transplant the whole thing to another case sometime..
i did the hum-mod (ground-rail-cut around the transformers) with good success.
now my question: the signal to noise ratio is best with the ouput pots set to 10'clock. this is somehow the most quiet setting. lowering or increasing the output both increases the noise drastically. i'd describe it as 20% hum and 80% hiss.
both ways behave in the same way independently from another, so i think it must be some general issue. if anyone had an idea..
thx in advance
http://img121.imageshack.us/slideshow/webplayer.php?id=image00173q.jpg
this is about my dual-1176 rev.j by jakob. after all, i'm very happy to be into diy again- apart from soldering cables every now and then
been reading a lot on this board and have a question... to contribute at least something, i link some pictures (blurry handy fotos, but...) of my dual1176 living in the ugly body of an behringer t-19xx. the piece is generally working and i use it often for my mixes. the enclosure is not so bad: basic drillings and the input/output-jack section that i just used as it was, same with the powerswitch. had to use different knobs- but i think they fit well. another extra are the lundahls, 1539 instead of 1540. therefore the ugly perfboards to get the different wirings connected to the main pcb.
the thing with the behringer meters: i just used the built in ones- at least they showed some activity after checking with different resistors. i made the first pair to show gainreduction, the second pair shows output always. (hey can your 1176 do that? 8) ) lacking a good idea for the frontplate lettering i'll probably transplant the whole thing to another case sometime..
i did the hum-mod (ground-rail-cut around the transformers) with good success.
now my question: the signal to noise ratio is best with the ouput pots set to 10'clock. this is somehow the most quiet setting. lowering or increasing the output both increases the noise drastically. i'd describe it as 20% hum and 80% hiss.
both ways behave in the same way independently from another, so i think it must be some general issue. if anyone had an idea..
thx in advance
http://img121.imageshack.us/slideshow/webplayer.php?id=image00173q.jpg
@ sir round
try to move the Power Transformer out of the box and see if it makes any difference.check the ground path and make sure there's no ground loops. also the output transformer from the right channel seems to be quite close to the power transformer, not sure if this is an issue ? is the hum equal in both channels ?
try to move the Power Transformer out of the box and see if it makes any difference.check the ground path and make sure there's no ground loops. also the output transformer from the right channel seems to be quite close to the power transformer, not sure if this is an issue ? is the hum equal in both channels ?
thanks for your reply, isophase
yes, the noise is equal on both channels. i couldn't tell by my ears which is the one closer to the power transformer. and it's not so much about humming than for the hiss. if there were any ground loops, a wrong ground path or so- i wouldn't have a relatively quiet unit at this one particular output pot position?!
yes, the noise is equal on both channels. i couldn't tell by my ears which is the one closer to the power transformer. and it's not so much about humming than for the hiss. if there were any ground loops, a wrong ground path or so- i wouldn't have a relatively quiet unit at this one particular output pot position?!
gswan
Well-known member
Check for hiss and hum in the unit with the inputs shorted, so there's nothing leaking in from external cables or sources (or input ground loops).
Dr-Mbogo
Member
Thanks for your reply Jakob,
I changed the FDH333 diodes with no success. I even tried with unmounted pots to the front panel. No change.
I do not undestand the second part of your message. "high-impedance" and "floating". What can I do here?
Different wiring of main and ratio board?
hi all,
i just finished my unit !!!
all the voltages are good, it passes sound ok, i've done the Q bias CAL no problem but the meter does not deflect in GR mode (stays still around 0dBVU) it doesn't compress neither
i've replaced the TL071 from the GR circuit but it did not change anything, also changed Q1 and Q10 (i havn't matched them yet) Q10 does affect the metering thougt.
could someone tell me where to look at next, i've been stuck for 2 days now...
also if someone could give me the right voltages for the TL071 ?
thanks a lot, will report back very soon !
i just finished my unit !!!
all the voltages are good, it passes sound ok, i've done the Q bias CAL no problem but the meter does not deflect in GR mode (stays still around 0dBVU) it doesn't compress neither
i've replaced the TL071 from the GR circuit but it did not change anything, also changed Q1 and Q10 (i havn't matched them yet) Q10 does affect the metering thougt.
could someone tell me where to look at next, i've been stuck for 2 days now...
also if someone could give me the right voltages for the TL071 ?
thanks a lot, will report back very soon !
Gege
Active member
hello,
I have a problem with one of my G1176:
It's a Mako RevJ
I have no low frequencies at all. There must be a low-cut at 200/250Hz.
Someone once had the problem?
I checked my voltages, they are good, all components are
in the right direction ...
My years 'electronic' are too far and the research it is very empirical to me, if someone has a trick I'm interested ...
Merci
I have a problem with one of my G1176:
It's a Mako RevJ
I have no low frequencies at all. There must be a low-cut at 200/250Hz.
Someone once had the problem?
I checked my voltages, they are good, all components are
in the right direction ...
My years 'electronic' are too far and the research it is very empirical to me, if someone has a trick I'm interested ...
Merci
Dr-Mbogo
Member
isophase said:
check the connection of wire no 4. It connects the meter and the ratio board. I had the same problem once.
I hope that helps.
Chris
thank you Chris,
i found the problem !!! the Meter rotary switch is faulty (on the side where the wire no4 connects
thanks for your perfect suggestion.
i'm running to the electronics shop right now tho by a new switch, will report back this evening !
i found the problem !!! the Meter rotary switch is faulty (on the side where the wire no4 connects
thanks for your perfect suggestion.
i'm running to the electronics shop right now tho by a new switch, will report back this evening !
Gege
Active member
Good for you isophase
Autoquote : No one has an idea ? It makes me crazy
Gege said:
Autoquote : No one has an idea ? It makes me crazy
drumminkiger
Active member
I found these knobs that look a lot like the ones on a stock 2-1176, thought i would pass it along since i spent a fair amount of time looking for something with this vibe, but wasnt the old school RCA ones. I didnt see a referance to them here anywhere so check em out, Cool looking knob!
http://www.satopartsusa.com/prod_detail/default.cfm?/2A3C2D30303164646B646D617F223C3730316464686468617F362A3164647F052B3A3D203A211D3029342B2134303721101164617F052B3A3D203A211A342D303E3A2B2C101164666A7329273631303164626B65A4/view.htm
http://www.satopartsusa.com/prod_detail/default.cfm?/2A3C2D30303164646B646D617F223C3730316464686468617F362A3164647F052B3A3D203A211D3029342B2134303721101164617F052B3A3D203A211A342D303E3A2B2C101164666A7329273631303164626B65A4/view.htm
gswan
Well-known member
drumminkiger said:
Page says not suitable for a 1/4" shaft, which is a shame.
Something similar also available from China here:
http://www.alibaba.com/product-gs/330957536/1_4_Vintage_Control_Knob_for.html
drumminkiger
Active member
Man, i dunno how i missed that! that really is to bad. It looks like its a 6.1mm hole though, and thats almost a 1/4" so i bet i can mod them to fit by gently drilling or fileing them since there plastic, hopefully it'll be a close fit. Since there is a set screw, there will still be enough grip on them to turn the pot's. Those other ones are pretty cool to, though i dunno if i need 100 of them
Similar threads
