Try examining this amplifier with a 10kHz square wave. What's the slew rate at full power?
The SPICE models for the AD8065 and LT1363 are available on the manufacturer's websites:
http://www.analog.com/en/amplifiers...mod-spice-models/resources.html?display=popup
http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1154,C1009,C1022,P1108,D11759
The SPICE models for the AD8065 and LT1363 are available on the manufacturer's websites:
http://www.analog.com/en/amplifiers...mod-spice-models/resources.html?display=popup
http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1154,C1009,C1022,P1108,D11759
Yeah, its definetly possible.peranders said:Maybe you should test your ideas with LME49810/830 also
Thanks!juma said:Great work Nikolai !
I will hardly be able to do the justice to the amp in few sentences.
We have had extensive listening sessions where we compared the amp with Creek 4330MK2 and
Creek 5350SE hooked up to Revel M22 monitors and Audio Physic Spark loudspeakers.
The most noticable difference is in the bass, which is tighter and better controlled.
and in the soundstage, which is more solid and precise but, suprisingly, less expansive.
The high are grain free. Overall, the amp is very dynamic and musical.
I'd like to second this.juma said:Great work Nikolai !
And thanks for sharing the link to the Yewen composite amp article (which I haven't seen before), which really is essential understanding your amp (at first I couldn't quite disassemble all those multiple feeback paths, now it has become clear, a very clever design idea).
- Klaus
I've made this amp on my own 2-layes PCB a couple weeks ago. Here are THD and IMD measurements. The right channel on the graph is the amp input, the left is the amp output.
So, what about the sound? Very transparent and clean, with good bass performance. Transfer of a vocal is very natural. I’ve compared this amp with my previous favorite amp http://astral-for.narod.ru/index/stones/amgen.gif. ZD-50 is just better at any type of music. My other components are 3-way homemade speakers (magnesium Seas Excel drivers) and AD1862 based DAC.
Actually, I think if 50W is enough for you, it will be very hard to find a better amplifier.
Here are some pictures
http://fotoplenka.ru/users/antecom/422197/
So, what about the sound? Very transparent and clean, with good bass performance. Transfer of a vocal is very natural. I’ve compared this amp with my previous favorite amp http://astral-for.narod.ru/index/stones/amgen.gif. ZD-50 is just better at any type of music. My other components are 3-way homemade speakers (magnesium Seas Excel drivers) and AD1862 based DAC.
Actually, I think if 50W is enough for you, it will be very hard to find a better amplifier.
Here are some pictures
http://fotoplenka.ru/users/antecom/422197/
Mbe I'm missing something here -- here's a phase-gain plot of the input stage --
An externally hosted image should be here but it was not working when we last tested it.
jackinnj said:
That part is just an input LP filter and buffer. I guess that the simulated plots from the first post done without this LPF.
Cheers
Alex
jackinnj said:
You need a fast opamp in an LPF if you want it to work properly up to fairly high frequencies (i.e. CD-player output can contain some components in MHz range) . AD8065 used probably because it has very low THD.
Cheers
Alex
Personally I do not see anything wrong with this frequency response (-3dB at 75kHz). If you think you need a more flat response, just reduce the values of C2 and C3, or do not install the input filter (then the input is R7).jackinnj said:
I already posted the amp frequency and phase response vs C3 graph http://www.diyaudio.com/forums/showthread.php?postid=1577734#post1577734
Hi Alex and welcome to my thread 🙂 !x-pro said:
Yes, because the AD8065 has a very low THD, even at very high frequencies. So I see no difference in the perfomance with or without it, except the SNR. Also the AD8065 has a very low input offset voltage.
Actually the U2 can be AD8065, LM318. The U1 I think can be ADA4898-1, but I did not test it yet...
Mykola,
Thank you very much for this excellent design!!! I have built a simplified version – one of 6 blocks that I need for my 3-way system. I could not believe my measurement results! Even with LM318 THD were lower than I can reliably measure with Juli@ (20W, 8 Ohm, 10kHz), that is below 0.0003%.
I also tested operation of the amplifier in Current Source mode. It works great!
I am not sure how to implement a power supply for 6 channels properly. Any ideas?
Thank you very much for this excellent design!!! I have built a simplified version – one of 6 blocks that I need for my 3-way system. I could not believe my measurement results! Even with LM318 THD were lower than I can reliably measure with Juli@ (20W, 8 Ohm, 10kHz), that is below 0.0003%.
I also tested operation of the amplifier in Current Source mode. It works great!
I am not sure how to implement a power supply for 6 channels properly. Any ideas?
jackinnj said:
There is no connection, unless the amplifier is band limited on the output, and that is not the case here.
Cheers
Alex