The mosfets was merely chosen to be similar to what Ovidiu used in in his regulator, at least in the version I used as start for my variant. Of course feel free to use whatever mosfet you'll find suitable. Just keep an eye on its power dissipation, a not too small package helps here.
@SY - thanks for your kind words as well! It's still busy here, so let's see after the holidays what we can do about boards
@SY - thanks for your kind words as well! It's still busy here, so let's see after the holidays what we can do about boards
Hi Adrian,
yes, this pre is for MM and for rather high output MCs. Alternatively, one can pair it with a nice step-up transformer (Cinemag, Lundahl...) and has a cute little MC-phono pre.
I'm sorry to say I just discovered that my original source of 2SC2547 does not have them anymore. That's a pity as I like that part!
C0G/NP0 ceramics are at least as good as good film caps, but you can certainly use also pp caps if you prefer. However, the mentioned ceramics are easier to get in the needed values.
Hannes
yes, this pre is for MM and for rather high output MCs. Alternatively, one can pair it with a nice step-up transformer (Cinemag, Lundahl...) and has a cute little MC-phono pre.
I'm sorry to say I just discovered that my original source of 2SC2547 does not have them anymore. That's a pity as I like that part!
C0G/NP0 ceramics are at least as good as good film caps, but you can certainly use also pp caps if you prefer. However, the mentioned ceramics are easier to get in the needed values.
Hannes
I did not find the time to work again on my P-P. I hope to find some time " between the days " as we say here. I also have a little project for a pre-pre.
It is based on the 70th design John Curl made for Mark Levinson ( the man ) so it somehow fits into the historical row and it also shares the ultimate simplicity of the High Octane.
I do not claim authorship in any way. I just plan to build it with parts that are available now.
It is based on the 70th design John Curl made for Mark Levinson ( the man ) so it somehow fits into the historical row and it also shares the ultimate simplicity of the High Octane.
I do not claim authorship in any way. I just plan to build it with parts that are available now.
I currently have Pro-ject phono box as a RIAA and i am looking for some improvement. This RIAA is my first one and dont have any idea how "good" this is.
I have experience in electronics, and no problem building this one. Could this RIAA be better than my current RIAA? My TT is Dual 1256 with Nagaoka MP-110 cart.
What PSU you recommend with this one?
I have experience in electronics, and no problem building this one. Could this RIAA be better than my current RIAA? My TT is Dual 1256 with Nagaoka MP-110 cart.
What PSU you recommend with this one?
Hi and sorry for the long delay!
In principle, you can use any low noise bjt that has sufficient collector emitter voltage rating and current gain (hfe). It will certainly sound not bad with other transistors. The same basically applies to the shunt mosfet, your part should be fine.
Funny that you mention it, I actually build my prototype into the box of a project phono box (see also the photo at the beginning of this thread). The project board is now lying around somewhere (well it actually was lying around somewhere already earlier). The original project phono circuit was also discussed here in the forum and from what I remember there existed even versions with wrongly implemented RIAA constants. With some modifications it sounded ok in my opinion. In any case, you should try and see yourself what you prefer.
Current consumption is I think around 30mA or so for 2 channels.
In principle, you can use any low noise bjt that has sufficient collector emitter voltage rating and current gain (hfe). It will certainly sound not bad with other transistors. The same basically applies to the shunt mosfet, your part should be fine.
Funny that you mention it, I actually build my prototype into the box of a project phono box (see also the photo at the beginning of this thread). The project board is now lying around somewhere (well it actually was lying around somewhere already earlier). The original project phono circuit was also discussed here in the forum and from what I remember there existed even versions with wrongly implemented RIAA constants. With some modifications it sounded ok in my opinion. In any case, you should try and see yourself what you prefer.
Current consumption is I think around 30mA or so for 2 channels.
My first posting on a forum will be a question:
I built your preamplifier with a PCI made by myself. The result of THD and noise were excellent (like published values), and sounds very good, but for a reason I still do not know, this pre saturates the output voltage by approximately + VCC for no apparent reason (at random times), but I can not detect RF oscillations or performance problems in the circuit (when running)...
I used different transistors in the circuit. Someone commented to me these transistors could be suffering from high shot noise or flicker, or is it not the case?
I appreciate if anyone has any suggestion or suspicion.
I built your preamplifier with a PCI made by myself. The result of THD and noise were excellent (like published values), and sounds very good, but for a reason I still do not know, this pre saturates the output voltage by approximately + VCC for no apparent reason (at random times), but I can not detect RF oscillations or performance problems in the circuit (when running)...
I used different transistors in the circuit. Someone commented to me these transistors could be suffering from high shot noise or flicker, or is it not the case?
I appreciate if anyone has any suggestion or suspicion.