For transistors the Toshiba 2SK2145 dual is still available 50 Volt, 300 mW 15 mS and noise figure under .5 dB. Bipolars like the KSC945 and KSA773 are readily available, complimentary, 300 mHZ and low noise. Dual P Fets are history though. The 2SK2145 has the disadvantage of sources tied though.
Maybe a nice tube for voltage gain. I will defer this to Wavebourn.
Maybe a nice tube for voltage gain. I will defer this to Wavebourn.
We tried something similar 2 years ago. It was not Behringer, but similar brand, same output power, class D.
It was an open-air garden listening session, with JBL 250TI LE speakers.
http://www.uwe-neidhardt.de/assets/images/JBL_250Ti_Jubilee2.png
The class D was unable to compete with complementary-differential power amplifier, also 2x300W, 2SK170/2SJ74 input, cascoded, MOSFET VAS and 4 pairs MJL1302/3281 output. The class D sound was more harsh, less fluent, less full-bodied.
The paper was in the Hewlett-Packard Journal and is reproduced in The Selected Papers of Bernard Oliver, pp. 311-317. I have that book handy for a change
An excerpt: "However, the drop across this resistance produced by the operating current is only Io/2go = 1/2 kT/q to Io/go = kT/q or from 13 to 26 millivolts. Over the temperature ranges from 0 C to 100 C, the junction drop of a silicon transistor will change typically by 250 mV, Thus, unless the biasing diodes ... track this change within a few percent, Io will be very unstable ... At present the most practical solution to the temperature stability problem appears to be to make Rc [the emitter resistors] many times larger than 1/go, and to rely on negative feedback to reduce the resulting distortion."
Also in the collection is his great paper Thermal and Quantum Noise, from Proc. IEEE, May 1965.
What a wig he was.
If you close local loop before buffer, and add resistor from buffer's input to output, you will get a version of "current dumping" amp. Try and compare. However you can't get high gain from such an amp, but low distortions on a wide band for sure.
Speaking of transistors, why you don't consider Zetex devices? I would call them "Toshiba of modern days", in terms of innovations.
Speaking of transistors, why you don't consider Zetex devices? I would call them "Toshiba of modern days", in terms of innovations.
Bingo. See my output stage for headphone amp. The whole package doesnt drift at all. very temp stable circuit. Surprised no one commented before as to why circuit was so temp stable.
Yes, they mention 2% for some of the parameters. A great idea; formerly they just sliced and diced and dumped into a big hopper before packaging, I guess. Having things off the same wafer was better than nothing, but this is a lot better.
Datasheet Version 2007-11-01, tied source and not tied gates ?
Still useful for input LTP ?
http://www.semicon.toshiba.co.jp/eng/product_detail/transistor/jfet/1253485_13588.html
Patrick
Still useful for input LTP ?
http://www.semicon.toshiba.co.jp/eng/product_detail/transistor/jfet/1253485_13588.html
Patrick
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2SK3320. Same electrical spec.
Even smaller package.
2SK3320?Junction FETs (Single/Dual)?TOSHIBA Semiconductor & Storage Products Company
Patrick
Even smaller package.
2SK3320?Junction FETs (Single/Dual)?TOSHIBA Semiconductor & Storage Products Company
Patrick
Dumped into a big hopper??? Shirley you jest..
I'da thunk either an expanded wafer, or waffle pack..
jn
Dumped into a big hopper??? Shirley you jest..
I'da thunk either an expanded wafer, or waffle pack..
jn
Typically they're scribed on a sheet of heat activated sticky plastic and stretched. Now they would probably use a vacuum pencil pick and place after that.
The same die dual issue would be what is the substrate, I thought it might be the back gate so isolated duals would have to be two die. We always bought them that way.
EDIT Sorry EUVL the FET's were drawn funny, and some symbols show the arrow at the drain.
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