Bass is from 4Hz, that should be enough for phono preamp.
R 07 is for gain, you can try to put 220 Ohm instead original 330 Ohm.
Ι wasn't reffering to the realistic schematic I was reffering to post #2 schematic
Ups, I was referring to the Realistic schematics, sorry 🙂
Don't know why bass is weak in schematic from post 2, but gain is easy adjustable with the same resistor in the NFB, R3 is 3k, lower value will have more gain, try with 2.2k.
Don't know why bass is weak in schematic from post 2, but gain is easy adjustable with the same resistor in the NFB, R3 is 3k, lower value will have more gain, try with 2.2k.
All the schematics posted have IC or transistors that I don't have.
Are there any other suggestions?
I have those transistors
2N5458 MPSA14 2N4401 78L05 bs170 2N3904 BC239/546B/549 2N3906 2Ν5087 7915
I have those IC's
LM324N TL072 TL082 RC4558 UA741 LF353
LM386 NE555 NE556 PT2399
And I have those diodes
1n4148 1n4733A 1N5231B 1N5404 1N4728A 1N4742A 1N5817 1N5819 1N4001 1N4002 1N4004 1N4007 bzx 15V
Are there any other suggestions?
I have those transistors
2N5458 MPSA14 2N4401 78L05 bs170 2N3904 BC239/546B/549 2N3906 2Ν5087 7915
I have those IC's
LM324N TL072 TL082 RC4558 UA741 LF353
LM386 NE555 NE556 PT2399
And I have those diodes
1n4148 1n4733A 1N5231B 1N5404 1N4728A 1N4742A 1N5817 1N5819 1N4001 1N4002 1N4004 1N4007 bzx 15V
Hi-Fi RIAA Phono Preamp
I builted the above preamp.
It's pretty decent except from a hum at lower frequencies that is barely listenable (is there any easy way to get rid of it?).
I supplied it with a laptop charger at 24V using the rail splitter that I have posted at post #3.
I hope that someone in the future can find it useful.
I builted the above preamp.
It's pretty decent except from a hum at lower frequencies that is barely listenable (is there any easy way to get rid of it?).
I supplied it with a laptop charger at 24V using the rail splitter that I have posted at post #3.
I hope that someone in the future can find it useful.
After that rail splitter from post 3 put some filtering capacitors, 1000uF will be good, from + and - voltage to ground.
You can even put resistors 100 Ohm in series before those 1000uF caps to make a high pass filter.
You can even put resistors 100 Ohm in series before those 1000uF caps to make a high pass filter.
After that rail splitter from post 3 put some filtering capacitors, 1000uF will be good, from + and - voltage to ground.
You can even put resistors 100 Ohm in series before those 1000uF caps to make a high pass filter.
Ι have 1000uF caps but they are rated for 10 Volts.
The next high value that I have is 470uF at 40 Volts. Will they do the trick?
So I have build it and put it inside an enclosure. If you want any images I would be glad to sent some.
I ma trying to build one for myself, dial got two turntables probably with a switch. Can you share you pics tks
I ma trying to build one for myself, dial got two turntables probably with a switch. Can you share you pics tks
Ι will have to find them first. I had them in my old facebook account.
Do you want the schematic or the enclosure photos? I don't have the preamp either I gave it to a friend of mine after I bought a mixer.
Sadly I can't find the photos but the schematics are here:
Hi-Fi RIAA Phono Preamp
For power I used a laptop charger at 24V using the rail splitter.
and added 2 filter caps as nironiro suggested in post #47. Before the enclosure there was a noise that was gone after I put the whole thing in a metal enclosure.
The schematic for the rail splitter is this:
https://i.stack.imgur.com/oMPkn.png
Hi-Fi RIAA Phono Preamp
For power I used a laptop charger at 24V using the rail splitter.
and added 2 filter caps as nironiro suggested in post #47. Before the enclosure there was a noise that was gone after I put the whole thing in a metal enclosure.
The schematic for the rail splitter is this:
https://i.stack.imgur.com/oMPkn.png
- Home
- Source & Line
- Analogue Source
- Simple phono preamp suggestions