Calamity amplifier
features
features
- Power Supply 2x20VAC transformer ~ +/-27VDC
- Bootstrapped VAS stage
- Transitional Miller Compensation, TMC
- Output more than 30 Watt into 8 Ohm
- Precision = THD 0.00004% at 1 Watt
Loop gain/phase plot?
Without the above, we don’t know if this is a good Lineup amplifier design or a good Lineup power oscillator design
😉
Without the above, we don’t know if this is a good Lineup amplifier design or a good Lineup power oscillator design
😉
Not good enough. How does it look into a 100 nF capacitive load? 50nF? 1uF?
The basic gain configuration looks very good, much like many NJM series JRC op-amps as shown on the bottom of the first page.Calamity amplifier
features
- Power Supply 2x20VAC transformer ~ +/-27VDC
- Bootstrapped VAS stage
- Transitional Miller Compensation, TMC
- Output more than 30 Watt into 8 Ohm
- Precision = THD 0.00004% at 1 Watt
View attachment 1336382
https://www.mouser.com/datasheet/2/294/NJM2068_E-217911.pdf
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Calamity uses 2x20VAC transformer rated 200-300 VA for stereo.Nico
Can I ask what size and voltage your power supply transformer was?
It is class AB with 200 mA bias.
I post my circuit again for newcomers.
THD is 0.000004% in simulation.
The squarewave is 10 kHz.
Attachments
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Posts unrelated to lineup's thread and design have been deleted. If yours got caught up in that then sorry but that is just the way it is,
@Nico Ras you should start your own thread for discussion of your own design if that is what you want.
There is better buy the S-parts: ECX10N20-S and ECX10P20-S.
They are specially selected.
Here is to buy directly from the manufacturer:
https://gb.profusion.uk/uk/ecx10n20-s
https://gb.profusion.uk/uk/ecx10p20-s
They are very good Lateral MOSFET.
They are specially selected.
Here is to buy directly from the manufacturer:
https://gb.profusion.uk/uk/ecx10n20-s
https://gb.profusion.uk/uk/ecx10p20-s
They are very good Lateral MOSFET.
Another thing that is good is that these lateral MOSFET has built in protection diodes.
So there is no need to protect with external zener diodes.
So there is no need to protect with external zener diodes.
If one is building amps with one P fet and one N fet output per channel (as in many of Lineup's interesting recent concepts), there is little need for paying extra for the 'S' 'matched' ones from Profusion. The close-binned 'S' items (they are aligned by same part only, not across NPN/PNP) would be a good idea if there were multiple same-part output fets per channel. No harm in paying extra if one desires, however.
In LTSpice it runs fine up to about 20Wrms into 8 Ohms. I will leave more qualified comments to lineup and others though.Would this run at 24v? I have a spare PSU
It will run of of the box.Would this run at 24v? I have a spare PSU
But for perfection I would change these resistors:
R2 = 820 Ohm
R4 = 1k2
R10 = 1k5
The gain is set with R10. Setting 1k5 will reduce the gain to suit +/-24V
As a matter of fact the first version was done for +/-24V
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