jensenmann
Well-known member
I built a 33609 clone quite some time ago with 1N4148 in the diode bridge and found it to be very noisy. A friend who´s EE in HF engineering suggested to use 1N4153 and the result proved that he was right.
Simple DiodeBridge Compressor
- Thread starter richiyobs
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TwentyTrees
Well-known member
For what it's worth I used 1N4153s in my 2254 clone, and it's more than quiet enough for professional work.
Are you still in contact with this friend? I'd really be curious to know how he came to this conclusion.
I recently read an interview about DBC20 by buzz audio....
they re using Schottky barrier signal diodes, and they choose this type for punchier sound....
looking at inner pics , only input tfx, the rest is opamp ,even if cheap one they can have a good distortion if pushed...
but i think you all know this device
DIODE BRIDGE COMPRESSORS - TIM FROM BUZZ AUDIO
they re using Schottky barrier signal diodes, and they choose this type for punchier sound....
looking at inner pics , only input tfx, the rest is opamp ,even if cheap one they can have a good distortion if pushed...
but i think you all know this device
DIODE BRIDGE COMPRESSORS - TIM FROM BUZZ AUDIO
Reading again the dbc20... The point four touched me!
4 - How does the adaptive ratio design of the DBC benefit how it compresses vs other compressors - what other ones is it similar to in this regard?
Tim Buzz Audio - There are many famous compressors that operate like this, the most notable would be the Fairchild 670. Basically the thing has a wide "soft knee" characteristic. The DBC will move from a low 2:1 ratio right up to 20:1 depending on how hard you drive it....
Measuring with CMT vst, noticed that ratio is also time depending... I was worried cause I couldn't get a fixed value... So since the Sidechain design I m running it s from a vari mu... can be it be considered adaptive?
Thanks for attention
4 - How does the adaptive ratio design of the DBC benefit how it compresses vs other compressors - what other ones is it similar to in this regard?
Tim Buzz Audio - There are many famous compressors that operate like this, the most notable would be the Fairchild 670. Basically the thing has a wide "soft knee" characteristic. The DBC will move from a low 2:1 ratio right up to 20:1 depending on how hard you drive it....
Measuring with CMT vst, noticed that ratio is also time depending... I was worried cause I couldn't get a fixed value... So since the Sidechain design I m running it s from a vari mu... can be it be considered adaptive?
Thanks for attention
5 - Why did you choose the particular diodes you have in the DBC, and how different would alternate diodes make the unit sound?
Tim Buzz Audio - We use Schottky barrier signal diodes and I chose these because they have the sound I wanted which was a bit more punchy than standard silicon diodes. Plus they also have very tight manufacturing tolerances so we do not need to match them, which saves labour and helps keeps the cost of the unit down.
Good to know
Tim Buzz Audio - We use Schottky barrier signal diodes and I chose these because they have the sound I wanted which was a bit more punchy than standard silicon diodes. Plus they also have very tight manufacturing tolerances so we do not need to match them, which saves labour and helps keeps the cost of the unit down.
Good to know
Even at faster setting and totally squashed...the design I m running results always smooth and no audible distortion, tested in mono of course with different program materials... But don t own the proper measurement tools to really judge
I'm not convinced at all.
In a diode bridge compressor, the diodes are not used to switch, nor operating at high frequency.
richiyobs, seems like the threshold is fairly high when I simulate it. seems like you could use one additional stage before the threshold to amplify the signal going into the sidechain, giving you more room to work (like you could compress lower level signals).
That is a quite common feature of feedback compressors. Only feedforward compressors (which tend to be mostly VCA-based) do not behave like that.
It's not really the structure of the side-chain that matters, it's how it is connected to the signal chain that makes a difference.
Since the side-chain samples the signal after the diode bridge, it's a feedback topology, so, yes, it has this variable-ratio characteristics.
What is not convicting you?
I m curious
Wow now I see!
Thank you so much
I could save your time... i got the LTspice asc
i could attach, it contains all the suggestions i received and also the out amp to check
Please do!
