| Full balanced current (transconductance) chip-amp - Click HERE for Original Thread |
| swak |
I have got a new soudcard with a set of full balanced outputs. As I have wanted to try a transconductance amp for some time I was wondering if I go for it in balanced mode.
As I am thinking will be building a 4 ch amp, input transformers would be too expensive. Can anyone advice me on a good wyz to do it ors point me to some schematics?
Thanks in advance. |
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| BWRX |
| I've got some LM3875 boards being made that can accept a balanced input. You can find the schematic here . I'll have about 20 extra boards, so if you're interested just let me know. |
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| swak |
BWRX, tahnks for the link and for the offer, I want to do this project P2P.
How about this design http://www.jensen-transformers.com/an/ingenaes.pdf ?
The idea also comes from an instrumentation amp.. if someone is willing to help me set the resistor values and the A1, A2, A4 Opamps (AD811?) I would give it a try and report how it goes. |
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| m8o |
swak, wondering if you use a Spice program, like LTSpice? I have some schematics.
I'm presently working on the designs and aquiring parts to tri-amp my front 3 Klipsch/JBL horn mish-mosh speakers using LM4780 chips as transconductance amps. I'm not sure if I'll turn my home computer on tonight, but if I do I'll take some screen caps of the schematics of the transconductance circuits I've been working on. If you use LTSpice, I can e-mail you the circuits.
edit: but the circuits are not balanced ins .... however, I guess I should do so as I purchased a BSS prosys ps-8810
( http://www.bss.co.uk/includes/produ...x?product_id=32 )
to perform the 3 channel 3-way crossover functions I need (with some minor eq'ing), which is balanced in and out.
To prototype, I bought 4 assembled boards from National Semiconductor. I plan to modify the circuits (cut the copper and add resistors as needed) to make it operate as a transconductance amp. |
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