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Old 11th January 2008, 02:52 PM   #1
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Default summing at the LTPI

Does anyone have some experience using a Long Tail Phase Inverter as a summing amp (passive summing at the 1st input)? What were the results? Any thing to watch for in such a design?

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Old 11th January 2008, 03:54 PM   #2
kevinkr is offline kevinkr  United States
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I used to build all of my bigger (>60W) PP amplifiers using global feedback fed to the inverting input of an LTP input stage.. Worked just fine.

Designed a 0 global feedback PP 300B amplifier that was published in VTV with an LTP as input stage with a balanced input option. Built a similar stereo 300B PP amplifier commercially, no global feedback with an LTP input normally configured for a single ended input, a balanced option was available, but no one requested it.

All worked just fine.

The VTV article is available on my site.
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Old 11th January 2008, 04:36 PM   #3
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Default thanks

That's about what I'm looking for. PP power amp in the 40-60W range (instrument app.). After posting here I thought about the old Fender stand alone reverb unit which basically does what I'm interested in. Thanks much.

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