Svart
Well-known member
excellent work butta!
Forssell Opto Compressor
- Thread starter sismofyt
- Start date
Help Support GroupDIY Audio Forum:
[quote author="buttachunk"]board complete. i used Miko's layout-- very nice !![/quote]
butta, how many people are working on boards? I like the idea of something unique to The Lab which is why I volunteered early on to do a single sided layout but it seems like there are more people working on pcb layouts than breadboarding the design itself!
butta, how many people are working on boards? I like the idea of something unique to The Lab which is why I volunteered early on to do a single sided layout but it seems like there are more people working on pcb layouts than breadboarding the design itself!
Ok, I've become "Miko" - I understand now. I thought MikoKensington had gotten in on the action too. Cool, I'm glad the layout was useful. It would be interesting to see your additions.
Let me know how it flies. I want to make up a single sided version of Fred's make-up section with his JFET990 + sidechain and nested pads for IC opamps if that doesn't end up duplicating someone else's work.
Let me know how it flies. I want to make up a single sided version of Fred's make-up section with his JFET990 + sidechain and nested pads for IC opamps if that doesn't end up duplicating someone else's work.
hitchhiker
Well-known member
hey Buttachunk, any luck with your proto?
Lance
Lance
hitchhiker
Well-known member
hi buttachunk,
I came up with same as you for R8 & R9. (both 5K)
For R4 I found some mention of 1K.
Mnats did a schematic that showed R4=1K R8=5K R9=1K R7=1K
(he has directly after R9 a cap and the 5K to the makeup amp.)
I found mention by Fred that R7 would fall between 100 & 200 ohms.
I have 150 ohms in I think.
I think you could find the link to Mnat's PDF in his later posts.
cheers,
Lance
I came up with same as you for R8 & R9. (both 5K)
For R4 I found some mention of 1K.
Mnats did a schematic that showed R4=1K R8=5K R9=1K R7=1K
(he has directly after R9 a cap and the 5K to the makeup amp.)
I found mention by Fred that R7 would fall between 100 & 200 ohms.
I have 150 ohms in I think.
I think you could find the link to Mnat's PDF in his later posts.
cheers,
Lance
Yikes - don't rely on my schematic for part values! I made the schematic mainly to generate a netlist for an accurate PCB layout. Punch whatever values are correct into the corresponding holes in the PCB. I think Fred said earlier some of my values were incorrect...use my schemo for placement only!!!
hitchhiker
Well-known member
hey buttachunk,
Good to hear you've got some proto's up and running.
I agree this design is a gem and if we could get one tracking well
in stereo there are some tracks we'd like it across the bus.
cheers,
Lance
Good to hear you've got some proto's up and running.
I agree this design is a gem and if we could get one tracking well
in stereo there are some tracks we'd like it across the bus.
cheers,
Lance
sorry to interupt but can you compare it to ssltype of compression, or commercially available units? :roll:
I should stop readin all this... makes me wanting start building to much and there's still a lot to finish first
Good work Buttachunk, i admire you, aiii :green:
I should stop readin all this... makes me wanting start building to much and there's still a lot to finish first
Good work Buttachunk, i admire you, aiii :green:
i know an opto isn't exactly an ssl alike, have a few opto's around in the studio but unfortunately i don't like them that much as they eat too much quality instead of giving. (focusrite platinumseries btw, disappointed me really but not expensive so it's more or less ok i guess)
hitchhiker
Well-known member
I agree the 5534 is a good sound .I tried one (no buffer),not minding that the compressor side chain would be affected some when the the comp was set to off or low (as Fred pointed out).
I then put in the tl072 and really was pleasantly surprised by how close the sound was to the 5534.
I wonder if all the trouble of a buffer is worth it for the chip make up in this
place? Can you test a tl072 and say what you think?
cheers,
Lance
I then put in the tl072 and really was pleasantly surprised by how close the sound was to the 5534.
I wonder if all the trouble of a buffer is worth it for the chip make up in this
place? Can you test a tl072 and say what you think?
cheers,
Lance
hitchhiker
Well-known member
Buttachunk,
yes, half the gain might be more than enough.
yes, half the gain might be more than enough.
hitchhiker
Well-known member
Buttachunk,
Super job! Having heard my proto I can imagine what you are hearing.
I have one other question. When you have it set to max compression ,
do you feel it could squeeze some sources a bit more without being a loss to it's good sound? In other words would you like the option of a bit more compression ?
Lance
Super job! Having heard my proto I can imagine what you are hearing.
I have one other question. When you have it set to max compression ,
do you feel it could squeeze some sources a bit more without being a loss to it's good sound? In other words would you like the option of a bit more compression ?
Lance
hitchhiker
Well-known member
Buttachunk,
understood. The reason I'm asking is that when I had my accidental version working with the 5C9 and the amp stradling the feed to the sidechain as your first schematic for the make up amp depicted,I had the option of alot of compression. When I later tested the circuit more like where you are now I found that I was missing a bit of compression that I had dialed in for some of my test material.
keep the good work.
cheers, :guinness: :sam: :sam:
Lance
understood. The reason I'm asking is that when I had my accidental version working with the 5C9 and the amp stradling the feed to the sidechain as your first schematic for the make up amp depicted,I had the option of alot of compression. When I later tested the circuit more like where you are now I found that I was missing a bit of compression that I had dialed in for some of my test material.
keep the good work.
cheers, :guinness: :sam: :sam:
Lance
rafafredd
Well-known member
Butta,
can you draw the FET buffer you are using? It´s just what I´m looking for in another project...
Thanks!
can you draw the FET buffer you are using? It´s just what I´m looking for in another project...
Thanks!
rafafredd
Well-known member
EDIT: Don´t make sense anymore.
hitchhiker
Well-known member
Buttachunk,
I found a non-connection on my breadboard from when I added the correct opto. Getting much more comp ratio now.Proto performs great now. How are your tests and measurements going?
Lance
I found a non-connection on my breadboard from when I added the correct opto. Getting much more comp ratio now.Proto performs great now. How are your tests and measurements going?
Lance
rafafredd
Well-known member
OK, Now I see...
I´ll be waiting for the entire circuit.
I´ll be waiting for the entire circuit.
hitchhiker
Well-known member
hey Buttachunk,
Looks great! I'm gonna give your new make-up amp a go,maybe tonight!
I hope you made out OK on the accident court case.
cheers,
Lance
Looks great! I'm gonna give your new make-up amp a go,maybe tonight!
I hope you made out OK on the accident court case.
cheers,
Lance
hitchhiker
Well-known member
hi Buttachunk,
I got your new make-up amp going but have a problem.
The signal was very faint so I tried swapping out the FET a few times, but
still the same . I got it to work as it should by removing C2. I tried
lowering the value to 100u and 33u but whenever C2 is in place it seems
to stop the FET.
The amp sounds very good,but there is a motoring buzz in the noise floor.
I have to crank the board channels to hear the noise well.
What's do you think is going on with C2?
Lance
I got your new make-up amp going but have a problem.
The signal was very faint so I tried swapping out the FET a few times, but
still the same . I got it to work as it should by removing C2. I tried
lowering the value to 100u and 33u but whenever C2 is in place it seems
to stop the FET.
The amp sounds very good,but there is a motoring buzz in the noise floor.
I have to crank the board channels to hear the noise well.
What's do you think is going on with C2?
Lance
