Wow, somewhere there's a huge disconnect. I think your work is a cornerstone for the SITs. If I've come across differently, it's a product of the internet, but not my intent.
I thought your papers were excellent. I'm trying to take a poll of sorts for ideas, my current default (as I told you in email) is your self biasing IXYS idea. If I can't find a better bet, that's my path.
with the times you will learn that the best path forward don't exist , it's just compromises. michael prefer his inductor load version , generg his resistor version , someone else will be the CCS . build the Amp Sit 1 as reference it is very special! , from there you could juge if the others variations will be better or not for your needs
That's awfully nice of you to say, but honestly I wasn't fishing for a compliment. I thought I had offended you, and I'm glad to hear I haven't.
I have advised a lot of people both here and privately to try the simpler versions first, not because I doubt anyone's ability but rather because I sincerely think it enhances the fun.
I have advised a lot of people both here and privately to try the simpler versions first, not because I doubt anyone's ability but rather because I sincerely think it enhances the fun.
That's awfully nice of you to say, but honestly I wasn't fishing for a compliment. I thought I had offended you, and I'm glad to hear I haven't.
I have advised a lot of people both here and privately to try the simpler versions first, not because I doubt anyone's ability but rather because I sincerely think it enhances the fun.
Respect. You are very talented. Please keep doing what you're doing. I'm certain there are many who benefit from your work who are not as vocal as I.
I've decided I will build this little amp to power some OB FR speakers. The speakers will be quasi-line arrays (either 2 or 4 drivers per channel). I will double up the circuitry in the amp and feed each amplification device from a single shared supply. Signal input to the amp will be via transformer output from my DAC, allowing a single-channel's pair of output devices to operate differentially. Each device will be connected on the output to 50% of the drivers, cross-wired relative to the other 50% to give proper phase response and noise cancellation. Device loading will be inductive.
A better application would be to drive both legs of a dual voice-coil differentially within a given driver. But I'm unsure I can get an appropriate dual voice-coil driver.
A better application would be to drive both legs of a dual voice-coil differentially within a given driver. But I'm unsure I can get an appropriate dual voice-coil driver.
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I believe in the begining of the thread, or in the articles you will find that info. The best is to use operating point paramaters, ie; 15Vds 2.5A or something like that. You will be putting some negative volts like -5 or so + or - a volt or so on the gate to acheive that... Check out the articles again, I think it's there
That's pretty much what's on my bench right now, minus the tail CS. I guess I can move on to something else and leave this one to the group.
Any news on the balanced version?
I hate the idea of huge electrolytics on the output although Nelson seems to prefer them to transformers.
Has anyone compared the SIT amp to ZV9?
I have some lovoltech fets which would be ideal for a simple l'amp style build head amp rated at a couple watts output. I do not think cascoding ala zv9 will be absolutely necessary as long as pre or dac has low output impedance.
In MR's L'Amp designs, it has been suggested by some that a bleeder resistor one side going to the connection of the 10000uF cap where it attaches to the speaker the other side going to ground might be useful (as seen in many of the Zen amps).
Other have suggested a bypass cap in parallel to the 10000uF cap.
Thoughts?
Other have suggested a bypass cap in parallel to the 10000uF cap.
Thoughts?
If you intend to energize and fiddle with the amp without a speaker connected, a bleeder to discharge the output cap is a good safety measure.
The cutoff frequency (-3dB) for the filter formed by the 10,000 uF output cap and an 8 Ohm speaker is:
Fc = 1/(2*PI*R*C(Farads)) = Hz
Fc = 1/(2*PI*8*.01) = 2Hz
The cutoff frequency (-3dB) for the filter formed by the 10,000 uF output cap and an 8 Ohm speaker is:
Fc = 1/(2*PI*R*C(Farads)) = Hz
Fc = 1/(2*PI*8*.01) = 2Hz
