Search found 5449 matches
- Thu Mar 28, 2024 9:52 am
- Forum: Build
- Topic: Phono Transfer System Construction Information
- Replies: 251
- Views: 6534688
Re: Phono Transfer System Construction Information
4.7µF, the max available in PP, should be large enough since it moves the cutoff frequency down to about 2.4 Hz. It varies a little bit as the gain jumper is moved from 10K to 14K3 to 20K for -3, 0, and +3 dB gain. The RIAA path through the first input has two coupling caps - one at the input the se...
- Thu Mar 28, 2024 9:34 am
- Forum: Pro Audio Design
- Topic: A Quadrature Power-Summed Compressor Sidechain For "The Uno Compressor"
- Replies: 41
- Views: 17163
Re: A Quadrature Power-Summed Compressor Sidechain For "The Uno Compressor"
I wanted to post a couple of other Ratio curves I simulated with the spreadsheet. The first is a linear taper rotation versus Ratio. Electrically 50% rotation is 2:1; 75% is 4:1. (The X-axis should start at 0.) https://proaudiodesignforum.com/images/png/Uno_Compressor_Taper_Linear_Pot.png The linear...
- Wed Mar 27, 2024 3:55 pm
- Forum: Pro Audio Design
- Topic: A Quadrature Power-Summed Compressor Sidechain For "The Uno Compressor"
- Replies: 41
- Views: 17163
Re: A Quadrature Power-Summed Compressor Sidechain For "The Uno Compressor"
bruno2000 aka Joe Neil published his Threshold, Ratio and Makeup mods here but I think I was asked to delete them.
- Wed Mar 27, 2024 9:10 am
- Forum: Pro Audio Design
- Topic: A Quadrature Power-Summed Compressor Sidechain For "The Uno Compressor"
- Replies: 41
- Views: 17163
Re: A Quadrature Power-Summed Compressor Sidechain For "The Uno Compressor"
The original Pico Stereo compressor used a threshold and ratio circuit where the pot element becomes part of a voltage divider. https://proaudiodesignforum.com/images/jpg/PicoSE_Threshold_Ratio.JPG At higher compression ratios small changes in control attenuation make for big changes in slope. Witho...
- Wed Mar 27, 2024 6:19 am
- Forum: Build
- Topic: Phono Transfer System Construction Information
- Replies: 251
- Views: 6534688
Re: Phono Transfer System Construction Information
These are working into a 14K3Ω load.
Wima now have some nice 5 mm lead spaced films in the MKS2 series that go up to 6.8µF so keeping them film is do-able.
Wima now have some nice 5 mm lead spaced films in the MKS2 series that go up to 6.8µF so keeping them film is do-able.
- Tue Mar 26, 2024 7:27 am
- Forum: Pro Audio Design
- Topic: A Quadrature Power-Summed Compressor Sidechain For "The Uno Compressor"
- Replies: 41
- Views: 17163
Re: A Quadrature Power-Summed Compressor Sidechain For "The Uno Compressor"
After clearing off the workbench to build some boards and spring yard cleanup I'm finally back to working on the Uno Compressor. During my break I thought a lot about the ratio control and wrote a spreadsheet to calculate trial values for a stepped switch and a means to linearize adjustment with a p...
- Tue Mar 26, 2024 7:06 am
- Forum: Build
- Topic: Phono Transfer System Construction Information
- Replies: 251
- Views: 6534688
Re: Phono Transfer System Construction Information
On the latest run of RIAA boards I added more capacitor footprints for C33-C36. We found that when used as a cutting amp, with feedback, a 47uF should be used to reduce phase shift at C33-C36 so I added an electrolytic footprint. https://proaudiodesignforum.com/images/jpg/RIAAEQMONSW_Universal_Capac...
- Tue Mar 12, 2024 5:21 am
- Forum: Build
- Topic: Phono Transfer System Construction Information
- Replies: 251
- Views: 6534688
Re: Phono Transfer System Construction Information
The rolloff at 20 Hz is intentionally introduced - to reduce warp - by the value of the film caps C33-C36.
You can make them much larger in value using electrolytics and it will follow the curve to 20 Hz.
You can make them much larger in value using electrolytics and it will follow the curve to 20 Hz.
- Wed Feb 28, 2024 7:22 am
- Forum: Pro Audio Design
- Topic: A Quadrature Power-Summed Compressor Sidechain For "The Uno Compressor"
- Replies: 41
- Views: 17163
Re: A Quadrature Power-Summed Compressor Sidechain For "The Uno Compressor"
I needed to assemble some boards for a client and had to move this off the bench for a few days. I should be getting back to it soon. One of the issues I found in the original Pico, and some of the earlier 4301 app notes, is that the "Over Easy" pre-bias diode was pulled up by a large valu...
- Fri Feb 23, 2024 6:45 pm
- Forum: Pro Audio Design
- Topic: A Quadrature Power-Summed Compressor Sidechain For "The Uno Compressor"
- Replies: 41
- Views: 17163
Re: A Quadrature Power-Summed Compressor Sidechain For "The Uno Compressor"
Updated Schematic. Gary Hebert of THAT suggested that I use a detector that is not "one Vbe up" at the timing capacitor node to reduce temperature drift between channels arising from the two channels being on different transistor arrays. The original dBx 303 detector and 2252 are one Vbe ...