Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.
Thanks for the input guys.
I have reviewed the web for headphone amp designs and found a motley collection of circuits out there. Some are unable to supply sufficient current for low Z phones. Others cannot supply sufficient voltage for hi Z phones. Some have no CMRR or PSRR. Some violate the...
I have been reviewing web posted discrete designs for output buffers for headphone amplifiers.
For discrete circuits it seems there is an overwhelming favorite. It is the Diamond buffer. I cannot see why it is favored over the common Complementary Symmetry PP topology. Perhaps someone can...
pinout,
I think I have a reasonable solution.
I talked with a designer of OPAs and he said that they routinely design them with Tj of 100 to 110C and have no problems with longevity.
If that is so, then in compliance with the data sheet, the 2N3904/06 transistors will be able to handle .35W...
I am putting together a complementary symmetry buffer using the 2N3904/06 combo. I plan to drive headphones with it.
For thermal tracking and some heatsinking, each pair will be epoxied face to face on a separate one in sq .062 alum heatsink.
Measurements have shown me that the internal...
Yes!
Man am I happy you brought that up. R3 will not help you in that event. That is why in the original circuit Elliott used a zener voltage snubber at the output. I forgot that! And I forgot the diode to prevent kickback through the CCS. That is probably not much of a problem with batteries...
Thanks, I goofed. I fixed it in the battery version below. I guess it will work OK with two 9V batteries. If not, simply add another for 27V.
The only question left is whether the LT1086 or LM317 can regulate current as low as 4 mA. Thoughts?
Sorry, I still do not understand.
If there is DC...
Based on your assessment of the westhost circuit, I pushed forward with it. Because of what I have on hand, it may be the simplest solution yet. If I haven't screwed up!
I hope your will critique what I came up with. The schema is below. First some clarification.
I used connector symbols for...
Thanks for the reply.
You are clearly correct. When I started this search I first went to OPAs. Very easy to use and excellent performance. But I want to put the circuit inside the mic wand body and had difficulty with an OPA. Also, a two wire circuit means a single ended supply and that means...
Re: Unbalanced "phantom" power
I am happy to see that you pointed to Brüel & Kjær. They one of the leading, if not the leading, measurement mic manufacturer on the planet. All of their CCLD systems are NOT balanced and they are NOT 600 Ohm. They use BNC (2 wire)...
Sorry you could not grasp that R8 with its value was not a working part. It was a placeholder for the sim and to help explain what I am asking about.
Given that one of the capsules I will be using will output only 6.3 mV at 1 Pa (94 dB SPL) and this is a buffer with a gain of less than one, I...
Sort of. This is what I had in mind.
V2 is an ECM mic. Green is input. Yellow is taken off of RL.
CC is the cable capacitance and that is where the connection is made between PS and buffer. I am using 30p per ft for 100 ft even though I will probably only use about 40 ft of cable. Note no...
chuckey,
Yes, balanced systems have been around since the advent of the telephone and are virtually exclusively used by the pro audio community. But there is often more than one way to skin a cat.
I am working on a measurement mic for at home measurement of loudspeakers. I want the simplest...
Good point. I figured the LED may as well do some work other than consuming energy all by itself.
The main reason I considered this is that when the load is plugged into the PS it turns on the LED showing that the load is powered and all is nominally fine. It also saves a switch.
Thanks
I would like to use an unbalanced two conductor interface to power an unbalanced buffer or amplifier and be able to pull off the AC signal to feed an ADC all using two conductors. PS could be anything from 9V to 15V and current draw anywhere from 3 mA to 30 mA (not at the same time this is for...
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.
