PCBs available for 1176-flavoured FET compressor w/ opamps - (almost) no wiring

Help Support GroupDIY:

fripholm

Well-known member
Joined
May 26, 2013
Messages
302
Location
DE
pstcho said:
yeah when slamm is pressed, i have it at 0

...which is backwards as to how it should be. That would also mean that in your case the switch's LED is lit when the button is NOT pressed, correct? If that's the case, something IS wrong with your SLAM switch.

The way it is designed, the LED is off (shorted, as well as R69) when SLAM is off.
 

pstcho

Well-known member
Joined
Dec 20, 2008
Messages
161
Location
Greece
ill check on that

my sciwtch is a classic  DPDT i didnt pay attention to the led if it switches accordingly

ill make more carefull tests and see

i need to follow the Qbias from the QB Spot also
 

fripholm

Well-known member
Joined
May 26, 2013
Messages
302
Location
DE
pstcho said:
my sciwtch is a classic  DPDT i didnt pay attention to the led if it switches accordingly

The BOM calls for a 4-way switch - 4PDT not dual.

You can make it work with a DPDT but only for basic Slam functionality. No LED indication nor R69 which increases the shortest release time when in Slam mode (1.8M is way to high for that, TBH).
 

pstcho

Well-known member
Joined
Dec 20, 2008
Messages
161
Location
Greece
my switch is like dpdt x2 on this picture ( down right )

it 1 switch with  4 ways NO/NC, i couldnt find the same switch ( in my country ) than the one of the BOM but seems to be the same switching method than on the datasheet ( i think )

 

Attachments

  • Capture.PNG
    Capture.PNG
    33 KB · Views: 15

pstcho

Well-known member
Joined
Dec 20, 2008
Messages
161
Location
Greece
Hey, yeah ok im super stupid all works perfectly, i forgot to remove the  jumper in the sidechain link .....

Now compresses perfectly, very very very discrete compression even at heavy reduction :) i like it, will be usefull on vocals and bass :)

thanks a  lot for your patience and sorry for my stupidity

i found it work better with 2N5457 than J112 or BA254
 

fripholm

Well-known member
Joined
May 26, 2013
Messages
302
Location
DE
pstcho said:
i forgot to remove the  jumper in the sidechain link .....

Great! Glad, you've found the error.

May I ask , what made you think to install a jumper there in the first place? Was it something misleading in the build guide?
 

pstcho

Well-known member
Joined
Dec 20, 2008
Messages
161
Location
Greece
i simply bought a kind of molex connector that had ajumper on it, when i soldered it i simply forgot to remove it

one week after before trying, i was ready the guide i saw  link so i didnt pay attention and fired it up , then you know the story :p
 

fripholm

Well-known member
Joined
May 26, 2013
Messages
302
Location
DE
Yes, the boards are available. Please see the first post in this thread on how to order by email (no PM, please).

Thanks!
 

uptownsquash

Member
Joined
May 27, 2020
Messages
20
Location
USA, Tennessee
Would it be possible to add the Poor mans tube gain stage to this project:
https://groupdiy.com/index.php?topic=43973.0

I think itll make for a fund and good sounding device. Ill be putting this into a 1U chassis so i should have the space for it.
 

fripholm

Well-known member
Joined
May 26, 2013
Messages
302
Location
DE
It should be possible if you replace everything after the output pot with the tube stage and an output transformer.
 

uptownsquash

Member
Joined
May 27, 2020
Messages
20
Location
USA, Tennessee
fripholm said:
It should be possible if you replace everything after the output pot with the tube stage and an output transformer.

sweet thank you, another question would this work for the right angle connector:

https://www.mouser.com/ProductDetail/TE-Connectivity/6-146309-3?qs=hegm%2Fm%252B%2Fz5nP%2FI%2Fg%2FM5trQ%3D%3D
 

fripholm

Well-known member
Joined
May 26, 2013
Messages
302
Location
DE
uptownsquash said:
sweet thank you, another question would this work for the right angle connector:

https://www.mouser.com/ProductDetail/TE-Connectivity/6-146309-3?qs=hegm%2Fm%252B%2Fz5nP%2FI%2Fg%2FM5trQ%3D%3D

No, at 8 mm the pin's mating side is too long.

Use these or these. And this is one possible female counterpart.
 

fripholm

Well-known member
Joined
May 26, 2013
Messages
302
Location
DE
uptownsquash said:
where would be the best place for me to pull audio front run to the tube gain stage?

If I understand correctly, you are trying to replace the output stage with your tube circuit, aren't you? In this case, you would pull the audio signal from the wiper of the output pot.
 

pstcho

Well-known member
Joined
Dec 20, 2008
Messages
161
Location
Greece
Hello, i really love this compressor, after using it quite a lot on vocals, id like to know if anybody tried to reduce the noise of the beast?
 

fripholm

Well-known member
Joined
May 26, 2013
Messages
302
Location
DE
pstcho said:
Hello, i really love this compressor, after using it quite a lot on vocals, id like to know if anybody tried to reduce the noise of the beast?

One of the goals when designing this was to reduce the noise to lower levels than my mnats 1176 clone has and the three channels I built are much quieter than that.

How much compression are we talking about and what other compressor units are you using for reference?
 

pstcho

Well-known member
Joined
Dec 20, 2008
Messages
161
Location
Greece
Thanks for your reply

it must be the most quiet i have and i really love the compression, its totally insane, just my preamp is even more quiet and id like to see if there was not a way to make it a bit more silent

i have a true bypass for the compressor and when i activate it, even then all the volumes are at 0 ( no signal ) i can hear the classic " white noise " , i didn't really mesure it yet but as the second quarantine is coming, i guess ill have plenty of time to do that

for that i see, only the ne5534 or the THAT 1646 could the "noise genrators "
 

Latest posts

Top