Leach Low-TIM amp with less power/lower voltage rails

[a.wayne]

For what it s worth, I have completed a design - with full documentation - on a fully compliementary amp that borrows heavily from Leach, but with a more modern slant and components. PCB's are laid out etc, but I have not had the time to order or build them yet - just too busy at work and its set to be that way for at least another 2 months. I am a bit reluctant to publish just yet, having not built the board and tested it.

I have another big 250W amp that's been runnung for 3 years, so I am pretty confident my latest effort is good to go.

Bonsai care to post details on your amplifier?

 

[Bonsai]

I have not built it yet, but I may put it up on my site. I may have to tweak some values once I've built it, and I prefer to have done all that before releasing any documentation. I'll have to think about it this week end.

 

[ostripper]

In resistively loaded LTP designs like the Leach, as long as the LTP current is held constant, the VAS standing current, pre-driver and driver standing currents are all fixed, and accurately.

Fully comp. and linn (blameless) , with all CCS's, will remain fixed (current wise) between 15v and 70V. Balanced topology will change slightly. A bootstrapped VAS is the worst... it will decrease in current with falling rails , increasing OPS dissipation with a standard EF2 BJT/Vbe combo.

OS