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First One - mosFET amplifier module

Thank you Lazy Cat,

The -in in your schematic are floating. Correct ?
Supply voltage in balanced configuration must be limited to +-45 Volt ?

In my schematic -IN is unconnected, it is marked NC, right, but -IN is actually internally (on PCB) connected to GND pin which is, like in schematic, connected to GND, so nothing is missing. If I would connect -IN pin we would get ground loop with interference currents like hum etc. but we don't want that.

Yes, supply voltage in balanced version is max.+/-45 V, which gives 140 Vpp of output sine signal and that is max current on 4 Ohm for the module to withstand. ;)
 
If you have to isolate them for whatever reason might be, it depends on the case. Microphone or vinyl pick-up have transformer very near because of low level signal to avoid noise, if preamp Zout is high put transformer near preamp, if preamp Zout is low than put transformer at the powr amp input. ;)
 
Happy new year LC, very very beautiful amp :up:.

"VSSA" did go bridged/balanced last in thread "First One" go bridged/balanced first in thread, seems world need power :D.
Hi BYRTT

Well the answer apeared and why not. For me only full balanced configuration, one amp module per each phase, is true balanced amp. It has meaning only to use with true balanced source providing both phases, so no OP amp phase splitter is nedeed.

Side effect is higher power, double slew rate and half damping. It was tested today it works with transformer as well as with balanced preamplifier. Sch from post #95 is correct and tested.

All the best in 2014 to you too. :cheers:
 
Today's system on repertoar
- NAS 2T Synology
- Network media renderer ABC
- DAC2 HGC Benchmark
- First One ESL
- Soul Supreme Zu audio

Dynamic and resolution of biblical proportions, music flows like an old malt whisky. :cool:

Nice setup.
Yesterday we also had a listening session: Foobar, DAC-END R ES9018, F5 (CLC PS), Refspeakers.
It sounded very good, mids and highs were superb, only the F5 was missing some power to control the double 10" woofers, it's time for The First One ;)
 
The F5 has 25W @8ohm and 40W @4ohm.
Yep, my speakers have two 10" Alcone woofers per channel, the speakers are 4ohm with a minimum dip of 2.8ohm at 100Hz.

Very good speakers you have Danny. :up:

I calculated you will get some +8 dB extra SPL with First One and around 112 dB SPL max, which is very satisfactory for home listening. ;)

Now I just have to provide them. :)