Being a CFB amp, only the 1K Rf position changes the current injection to the input node so the voltage gain division ratio does not modify crucial parameters? Is that a right way to sum it up?
i will write up on this one tomorrow Cristophe.
R11 and C12 sets the bandwidth and R11 and R12 is an "emitter" resistor at lower frequencies.
By set emitter to 50R instead of 100R we raise the open loop gain by +6dB but at the same time we increases the closedloop gain by +6dB. => loopgain is untouched.
R11 and C12 sets the bandwidth and R11 and R12 is an "emitter" resistor at lower frequencies.
By set emitter to 50R instead of 100R we raise the open loop gain by +6dB but at the same time we increases the closedloop gain by +6dB. => loopgain is untouched.
Tomorrow never came
Sorry.. We have just been to busy.
We work 7 days a week. Have hired an engineer and an assembly lady. Will maybe need a Technician also.....
You could change R1 to 22 - 100K only there will be a offset step when you connect/unconnect you source.
excellent diagram
I never saw such 8one amplifier, very good contribution.
Thanks Lazy Cat
Best regards Sergio.
POSTSCRIPT: Have the pcb
This update enables TSSA BIGBT HP to be even more universal:
- serial diode MUR160 plus 22 ohm resistor in power supply rails helps to improve PSRR
- +/-OPT pins enables to connect separate power supply for the front-end (MUR160 and 22 ohm are omitted)
- power supply LED indicators for both front-end and output stage are present
- serial compensating resistor added to NTC (serves to calibrate NTC thermal response)
- serial resistors added to SK75 heatsink's GND connection (serial RC filter)
- 1 uF/63V decoupling capacitors added close to VAS transistors supply rails
- TLP627 input now accepts 12 V remote signal (serial resistor added)
- LT1034 replaced by TL431
- R2-R9 values stated for +/-50 V power supply rails
And that's about it.
I never saw such 8one amplifier, very good contribution.
Thanks Lazy Cat
Best regards Sergio.
POSTSCRIPT: Have the pcb
pcb
Have the pcb in pdf format to do it in the plate method is that it is an excellent PCB. and iIn addition to the suggestions corresciones and Lazy Cat'm great.
Yes it is nice and compact CFB amp, thanks for kind words Sergio.
Probably Marc will be the first to assemble TSSA as he already populated PCBs to certain level.
Yes it is nice and compact CFB amp, thanks for kind words Sergio.
Probably Marc will be the first to assemble TSSA as he already populated PCBs to certain level.
Yes i do beut weather is against me....i wanted to populated second board and achieve first test this morning........but when i oppened yese this morning i just can cry : this night ia rain under negative tempco, i took the whole morning to scrape iced an defrost car......
Marc
The lower limit/threshold of hearing seems to be somewhere between .1 and .01%. So, I would make it 5-10 times better than that for each component in the 'system'... so that if the entire playback system was measured, the THD would be under that threshold. The simplist design which can do this and all other audible artifacts is the best design.
Thx-RNMarsh
The lower threshold is indeed relatively high .. But if you have multiple components that adds 0.1% it starts to be dominant.
We can only agree, Richard. While i believe the actual methods to measure errors are far to represent the all landscape.
It is time for a young and courageous engineer to work an a method and to propose the measurements instruments able to evaluate all the errors at once in the real music landscape.
Comparing an calculating the differences that occurs dynamically with real music, digitally and computer based.
We will loose a lot of fun, fighting in forums