Why don't they just make a class A opamp IC with that current sink in place already? External heatsink may be required. No one likes a heatsink on a 8pin DIP.
You get really low distortion if you use the NE5534 inverted and 8mA CCS to the POSITIVE supply. To have then a high input impedance you need a Buffer. That can be a compensated NE5534. I use that in a headphone amp i designed and nobody is complaining.
The output of the headphone amp is a modified Diamond buffer.
The output of the headphone amp is a modified Diamond buffer.
I suggest SR PP12 preamp from thread: http://www.diyaudio.com/forums/solid-state/173462-studio-reference-amplifier-180.html
A big n' nasty 220uF coupling cap on the output?
Can the offset not be controlled with a trimmer(s) somewhere in the circuit or with a servo?
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The old superstitions are alive and kicking 😀
.... I'm finding increasingly that capacitors done right, in the signal path, are a non-issue. On the output between amp and speaker is a bit different but there are options.
.... I'm finding increasingly that capacitors done right, in the signal path, are a non-issue. On the output between amp and speaker is a bit different but there are options.
No superstitions...I avoid them when I can, especially a capacitor that size which would obviously have to be an electrolytic.
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I really like modern electrolytics, they're small in size, nice and shiny and sound just fine to me - especially those audio bipolar types... In fact these days I use electrolytics where I can and my amps sound super good judging by what others have to say about them. Strangely, I don't use film caps much, bulky, awkward and the pricing of them make me laugh ! For small caps you can't go wrong with a quality C0G.
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The OP asked for transistor preamp, lets give him what he wants.
I built this one also and the results are very good.
A Simple, HIGH QUALITY Transistor Preamp
I built this one also and the results are very good.
A Simple, HIGH QUALITY Transistor Preamp
Very high gain again, designed for the Mic / Phono stage.
The OP is asking for a line stage with 4-6 db gain.
A number of good options is already presented.
Not Been Build Yet
Discrete transistor, Class-A (12mA), Current feedback, gain of 6dB.
Fast & low THD (0.0043% @ 20kHz; 2Vpk; RL 10k; CL 500p)
🙂
Not been built yet, but should operate well.
Discrete transistor, Class-A (12mA), Current feedback, gain of 6dB.
Fast & low THD (0.0043% @ 20kHz; 2Vpk; RL 10k; CL 500p)
🙂
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Thank you.I saw the schematic and it has ceramic pickup and magnetic pickup. How can I modify it to work on ipod level input?
Ok, I guess our Friend jrp27 just earned a custom design 🙂
with lots of jugaad, of course 😀
I don´t want to even *imagine* what kind of chassis it might be housed in 🙂
with lots of jugaad, of course 😀
I don´t want to even *imagine* what kind of chassis it might be housed in 🙂
It's a good performing & well behaved transistor, first image below. I bought 200 of them (total cost: $13.50) from Mouser: sales link
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The site is in French but here you have 9 preamplifiers transistors with different gains. With an online translator you should get out.
schémas simples de préamplificateurs BF à transistors ~ Schemas Montages realisation Electronique
schémas simples de préamplificateurs BF à transistors ~ Schemas Montages realisation Electronique