Search found 57 matches
- Fri Mar 01, 2024 4:29 pm
- Forum: Diode Bridge Compressor
- Topic: First build
- Replies: 27
- Views: 2040
Re: First build
For GR indication, I ran a cable on underside of board from sidechain CV1 out to onboard J13 (CV1 VU meter driver input). Stuffed R93 and R94 with resistors equivalent to VU meter resistance. Looking good for now. Value of R93 and R94 will depend on what meters are used but probably resistor equali...
- Thu Feb 29, 2024 3:58 pm
- Forum: Diode Bridge Compressor
- Topic: First build
- Replies: 27
- Views: 2040
Re: First build
In the schematic they are just blank resistors so I was looking for confirmation that I have these shown correctly. Those values look good to me. If your timing cap is 1uF your attack is approximately variable between 1 ms and 50 ms and release between 50ms and 550ms + attack time. What vu meter sp...
- Wed Feb 07, 2024 1:03 pm
- Forum: Info
- Topic: New Users!
- Replies: 3
- Views: 1733
Re: New Users!
During registration you will be asked a question to prevent spambots from registering. Send me an email and I will give you the answer.
- Sun Feb 04, 2024 9:01 am
- Forum: Open Source PCB Design
- Topic: Transformerless Feedforward Vari-Mu
- Replies: 3
- Views: 734
Re: Transformerless Feedforward Vari-Mu
Recom R12-150B
Regulators for the DC-DC converters are 12V and regulator for the heaters is 5V.
R1 = 1 ohms
R2 = 2.2 ohms
R3 = 4.7 ohms
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Regulators for the DC-DC converters are 12V and regulator for the heaters is 5V.
R1 = 1 ohms
R2 = 2.2 ohms
R3 = 4.7 ohms
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- Sat Jan 27, 2024 2:13 pm
- Forum: Diode Bridge Compressor
- Topic: First build
- Replies: 27
- Views: 2040
Re: First build
More accurate resistor values for the gain switches.
140
170
190
240
280
350
440
560
730
1k
1.4k
The values on the schematic have a tolerance of approximately +/- 0.1dB. Values listed here should be closer to +/- 0.02 dB
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140
170
190
240
280
350
440
560
730
1k
1.4k
The values on the schematic have a tolerance of approximately +/- 0.1dB. Values listed here should be closer to +/- 0.02 dB
-
- Sat Jan 20, 2024 3:59 pm
- Forum: Diode Bridge Compressor
- Topic: First build
- Replies: 27
- Views: 2040
Re: First build
Here is the libre office spreadsheet I used to create the curves
http://ghr.fi/proaudio/diodecomp/diodi.ods
http://ghr.fi/proaudio/diodecomp/diodi.ods
- Fri Jan 19, 2024 12:24 pm
- Forum: Diode Bridge Compressor
- Topic: First build
- Replies: 27
- Views: 2040
Re: First build
I'll need to check if I still have the ideal values somewhere. The E standard values should be pretty close to 1 dB per step.
- Fri Jan 19, 2024 10:36 am
- Forum: Diode Bridge Compressor
- Topic: First build
- Replies: 27
- Views: 2040
Re: First build
You don't necessarily have to measure anything when adjusting RV1. Just set it where the LEDs are starting to light up. The more accurate way to set it is to feed the channel input 1kHz signal and adjust threshold to make sure there is NOT any gain reduction happening. Monitor the output and adjust ...
- Thu Jan 18, 2024 7:21 pm
- Forum: Diode Bridge Compressor
- Topic: First build
- Replies: 27
- Views: 2040
Re: First build
Just as long D73 and D74 are the same type of silicon diode the exact type shouldn't matter too much. If RV3 and RV4 are 1k instead of 500 ohm it will change the threshold range. Exact type of diode shouldn't matter in the diode string and any silicon diode should work. Again just as long as they ar...
- Mon Jan 15, 2024 6:50 pm
- Forum: Open Source PCB Design
- Topic: Transformerless Feedforward Vari-Mu
- Replies: 3
- Views: 734
Re: Transformerless Feedforward Vari-Mu
Specifications Input impedance ≈ 12k ohms, balanced line-to-line * S/N > 86 dB re +4 dBu, 22 kHz BW, unity gain Frequency response = 20 - 20 kHz, ±0.5 dB Gain = 0 dB at limit mode, 6 dB at compress mode Output impedance = 50 ohms, balanced line-to-line - * INA2137 Internal resistors are ratio matche...