Pro Audio Design Forum

I built the circuit with some minor modifications. https://www.ka-electronics.com/images/jpg/Op_Amp_Booster_Stage_72_Volt.JPG With +/-31.5V supplies I can get just under +29 dBu, ~22 Vrms. I used an LME49710 and a BD139/BD140 pair. I increased Rb to 120R to eliminate HF crossover distortion. If I ge...

The databook is dated 1990.

Here's another booster stage that I had forgotten about using readily-available components. No need to use the OP37. I'd like to try it with modern parts. This one swings within about 1V of either rail. https://www.ka-electronics.com/images/jpg/Op_Amp_Booster_Stage_72_Volt.JPG Op Amp Booster Stage +...

"The Morgan Compressor Limiter," Michael Morgan, Precision Monolithics Audio Handbook Vol 1, Application Note AN-135, 1990. The following application note was written by Michael Morgan, a consultant to PMI with extensive experience in the design of professional audio equipment, including ...

I just checked a hunch that one of the reasons LEDs are used as voltage bias sources is that they have a sharper knee characteristic. This seems to be the case. The horizontal axis is 0.5V/div the vertical 100 uA/div. The left trace is a red LED I-V curve. The right trace is the I-V curve of three s...

NXP Matched Small Signal Transistor Pairs

Now Nexperia: https://www.nexperia.com/products/bipol ... stors.html

A Phantom Boost Converter using the TI TPS61170 with a voltage doubler output. https://www.ka-electronics.com/images/jpg/Phantom_Supply_Boost_Converter_TPS61170.JPG 48V Phantom Power From A 4.5 to 15V Input Supply Using the TPS61170 Boost Converter TPS61170 Data Sheet: www.ti.com/lit/ds/symlink/tps6...

The Electronic Design insert from Linear Technology this month features applications for the LTC6090 high voltage op amp. Linear Technology Design Note 513: http://cds.linear.com/docs/en/design-note/dn513f.pdf The 9V to +/-65V boost converter in Figure 2 in caught my attention. Unfortunately it uses...

JR - Is your house pier and beam with the outlets fed from below? If so you may be able to ground them. We drilled with a flex extension through the outlet box, through the bottom 2x4 plate and sub-floor and then fished in ground lines with the bit as it was being retracted. We were able to do all b...

Very ambitious project.

I have to wonder what kind of shape the electrolytics and F-series switches are going to be in.
For the sake of the pots I hope the desk was covered when it was stored.

BTW your garage is much cleaner than mine.