Search found 17 matches
- Wed Jun 10, 2015 10:38 pm
- Forum: Document
- Topic: DC Servos and Digitally-Controlled Microphone Preamplifiers
- Replies: 12
- Views: 21417
Re: DC Servos and Digitally-Controlled Microphone Preamplifi
Servo is more complex than AC coupling for sure, but I would say maybe equally or less complex than a hybrid design that is DC stable without the need for a servo. Putting a monolithic matched pair front end on an op-amp (curse the thought of degrading the monolithic pair by marrying it with an op-a...
- Wed Jun 10, 2015 6:43 am
- Forum: Document
- Topic: DC Servos and Digitally-Controlled Microphone Preamplifiers
- Replies: 12
- Views: 21417
Re: DC Servos and Digitally-Controlled Microphone Preamplifi
In my experience servos are an evil best avoided at all costs. They add a whole lot of disadvantages of their own. What's wrong with a dual current sink on input differential LTP and gain setting resistor set between the LTP emitters or emitter degeneration resistors? With good match and trimming co...
- Sat Jun 06, 2015 3:39 am
- Forum: Document
- Topic: reducing distortion in transfer gates
- Replies: 2
- Views: 7490
Re: reducing distortion in transfer gates
What a terrible thing to do to an audio signal.
- Sun May 10, 2015 1:18 am
- Forum: Pro Audio Design
- Topic: PCB layout - ground plane for PSU/star point
- Replies: 7
- Views: 20934
Re: PCB layout - ground plane for PSU/star point
I've always preferred ground plane on the opposite side of the component layer to have much greater coverage with less irregularities caused by components eating up the ground plane real estate. Running signal and power on the component side with traces, no power planes. Does a star return on a PCB ...
- Wed Jan 21, 2015 8:18 am
- Forum: Build
- Topic: Simple pcb design program
- Replies: 28
- Views: 110472
Re: Simple pcb design program
Is this too simple for what you need? http://www.expresspcb.com/ EDIT: Maybe you are tied into using their PCB services. EDIT2: Just read the other thread about PCB design programs. Forget what I said. I used to use a DOS version of Protel and really loved using keystrokes. It's amazing how many you...
- Fri Jan 16, 2015 9:23 am
- Forum: Pro Audio Design
- Topic: Distortion and source impedance in JFET-input op amps
- Replies: 13
- Views: 31292
Re: Distortion and source impedance in JFET-input op amps
That OP seems to be a little mmm well actually kind of sucks IMO. Class B with some deadband (crossover region) help from R50. I can see why it would want to oscillate with capacitance on its output. R50 is between the class B stage and the feedback loop. That junction feeds the OP. So it seems to m...
- Thu Jan 15, 2015 8:12 am
- Forum: Pro Audio Design
- Topic: Distortion and source impedance in JFET-input op amps
- Replies: 13
- Views: 31292
Re: Distortion and source impedance in JFET-input op amps
I'll have a stab at this from an analysis point of view. Mind you I don't believe I have any practical experience with issues that may necessitate the use of R8. I read the previous analysis regarding breakthrough and I am not arguing that side when the pot wiper is at ground. What I see is a DC com...
- Mon Jan 12, 2015 10:44 pm
- Forum: Document
- Topic: Nichicon Audio Capacitor Page at Mouser
- Replies: 8
- Views: 14142
Re: Nichicon Audio Capacitor Page at Mouser
Thanks for sharing your experience JR. When I first started doing this stuff I took many dead ends. Had to find my way back out many times. It doesn't happen that much now. I suffer from very little expectation bias anymore, it was a long time ago that emotional trait was dispensed with. I have no e...
- Mon Jan 12, 2015 10:43 am
- Forum: Document
- Topic: Nichicon Audio Capacitor Page at Mouser
- Replies: 8
- Views: 14142
Re: Nichicon Audio Capacitor Page at Mouser
It was a long time ago Ricardo. It was coupling an audio signal between a custom developed DAC and power amplifier. In that exercise the coupling caps were compared to each other and replaced with copper wire as the final test. All tests were done by ear. No test equipment was used. It was pretty ea...
- Sat Jan 10, 2015 10:06 pm
- Forum: Document
- Topic: NXP (Nexperia) Matched Small Signal Transistor Pairs
- Replies: 1
- Views: 7482
Re: NXP Matched Small Signal Transistor Pairs
I understand these, and many others like them, are two singles sharing a common package rather than a single monolithic die with two transistors.
I am currently using the BCV62 for a current mirror in a design for a high performance motorsport application.
I am currently using the BCV62 for a current mirror in a design for a high performance motorsport application.