If you are going to use a single number to compare amplifiers SINAD is as good as any, however, a single measurement like SIDAD does not give much of an indication of how an amplifier will sound.
On another note look at the 10W FFT of the Starkrimson output. the harmonics are more than 130dB down. This means they are completely inaudible. 130dB down is equivalent to 15pW (0.000000000015) into 8 ohms.
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I'm not going to say anything against you, especially since I don't have your expertise. In any case I am convinced of the quality of your products and the many comments suggest their effectiveness) I do not have your level of knowledge. Thank you for this very interesting feedback. 🙂
@Hurtig. Impressive work 
Do you mount the components yourself? .... tried the DirectFET ... not so easy to do by hand 😉
2 layer?
Do you mount the components yourself? .... tried the DirectFET ... not so easy to do by hand 😉
2 layer?
DrMordor, so you have an extra Schottky from Vss+12V to Vcc, for symmetry??
Could you explain a bit more?
Thanks and BR Baldin
D
Deleted member 148505
It looks like a reverse DC protection diode for VCC (VCC is supplied externally).
The other schottky is for bootstrap diode for Vbs supply. Just used SS1H10 althroughout to save on mass production PCB assembly.
The other schottky is for bootstrap diode for Vbs supply. Just used SS1H10 althroughout to save on mass production PCB assembly.
On another note look at the 10W FFT of the Starkrimson output. the harmonics are more than 130dB down. This means they are completely inaudible. 130dB down is equivalent to 15pW (0.000000000015) into 8 ohms.
In my opinion prior to building my amp I did some research which class D has the best specs and with others who already built Class D with ICEpower,Hypex,TriPath and Purifi, one of the member here giving a slight edge to Starkrimson and Purifi second due to SNR,THD,Gain and SINAD results are very good specs and the implementation of GaN on Leo's design that sold me to go with Starkrimson module 🙂
D
Deleted member 148505
Noob question: If you set 0dBrA as 10W into 8 ohms, would the harmonics still get 130dB down?
10W is about 11dB down from 0dBRA. So the harmonics are down about 120dB from 10W level.
However the power in the harmonics is still the same 15pW.
However the power in the harmonics is still the same 15pW.
D
Deleted member 148505
@Hurtig. Impressive work
Do you mount the components yourself? .... tried the DirectFET ... not so easy to do by hand 😉
2 layer?
It's a 4 layer PCB, and most SMD are mounted by the PCB manufacturer. Life is to short for hand soldering hundreds of SMD parts 🙂
The DirectFET's are soldered by hand. Actually pretty straight forward after some 50-100 times. I wasted quite a handfull before I managed to do the trick
Besides the small 50x80mm class-D, we also did an Extreme Edition...
The size is 180mmx230mm.
The class-D circuit is pretty much the same as the small one, except the DirectFET are chaged to TO-220 package and the output inductor is a toroid version.
The board contains all the features and performance of the small version, and adds:
- Approx 100.000uF of LOW ESR capacitors. Both +/- 60VDC and +/-15VDC.
- Rectifier for +/- 60VDC and +/-15VDC.
All it needs is 2x40VAC and 2x15VAC transformers.
Hope you guys like our approach to class-D.
The size is 180mmx230mm.
The class-D circuit is pretty much the same as the small one, except the DirectFET are chaged to TO-220 package and the output inductor is a toroid version.
The board contains all the features and performance of the small version, and adds:
- Approx 100.000uF of LOW ESR capacitors. Both +/- 60VDC and +/-15VDC.
- Rectifier for +/- 60VDC and +/-15VDC.
All it needs is 2x40VAC and 2x15VAC transformers.
Hope you guys like our approach to class-D.
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Well done!!! lovely !!! I don't like the irs 2092 chip ... The latest irs chip is better the done?
your board is just magnific!!! 🙂
your board is just magnific!!! 🙂
Agree... We do not use 2092... We picked out the IRS20957, since it contains the short circuit protection.
"Søren" aka Kurt von Kubik started the marketing campaign of the "Tomahawk" amplifier in another thread
Price for the "Tomahawk" 435 USD excl vat and shipping.
It would be nice if they would post open loop gain plot, phase plot as well as clipping behaviour of the amp. 😉
Price for the "Tomahawk" 435 USD excl vat and shipping.
It would be nice if they would post open loop gain plot, phase plot as well as clipping behaviour of the amp. 😉
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Call it gain plot if you like, but yes even a self oscillating class D amp has an open loop gain and phase plot.
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These are only prototypes... So no prices 🙂
If people in here are interested, we will do a small production.
These plots will be posted. Just need to do some more testing.
Why are you so focused on clipping behavior? I would prefer no clipping 😀
The Tomahawk Kurt von Kubik has posted earlier, is without rectifiers and the 100.00uF