What phono preamp circuit?

[Shaun]

What phono preamp should I build? There are so many phono circuits available, it is hard to know which are worth giving attention to. I would like recommendations for a working design (preferably with PCB layout, maybe even a kit).

The design can be either IC-based or discrete (not valve) and must have excellent noise, accuracy and dynamic range performance (compared to, say, the average integrated stereo amp). It must have a moving coil amplifier and should also accept a moving magnet input.

I will consider all designs from a stand-alone phono preamp to a full preamp with line level input select and volume control (prefereably electronic & remote control). If possible, I want to avoid having to design this myself; I just don't have enough time for it.

Thanks in advance for you inputs.

 

[Mooly]

Douglas Selfs new book has all you are looking for,

The Audio Power Amplifier Design Handbook

There are no PCB layouts but the designs are "state of the art" and IMO should be required reading for anyone interested in this field.

 

[Shaun]

Thanks, Mooly. I may just get that book.

Still seeking recommendations, however. Preferably circuits you have heard.

 

[peranders]

I have two designs but they are maybe overkill for you?

 

[Shaun]

Hi Peranders

I'm checking your web site. But perhaps you can give a quick rundown?

The QSX MkII looks interesting. Looks like what I had in mind, as it goes beyond the mere functionality.

 

[prakit]

Borbely Audio

Erno Borbely offers a few fet-based, as well as tube phono kits. Pricey but they are among the best available.

Best

 

[peranders]

Shaun, feel free to ask anything. The QSXM2 is a monster but it works and has done so since 1986. You can also use almost any part you'll like and for serious MC cartridges you can use MAT02/03 or the cheaper (and equal) SSM2210/SSM2220.

 

[Shaun]

I don't really know what to ask. There's a fair amount of info on the project pages. Ah, here's one: how critical is the power supply? Would an LM317-regulated PSU do?
Also, are there any PCB's available for this preamp?

 

[forr]

What about Marcel van de Vegel's design using "electronic cooling" (Electronics World, October 2003, pp38-43) ?

Based on the same principle, Self proposed his own version in his book "Small Signal Audio Design".

Curiously, the link mentionned by Mooly has the wrong title but points to the right book. Just happened the same thing to me. Another link :

Amazon.com: Small Signal Audio Design (9780240521770): Douglas Self: Books

However this link tells : "temporarily out of stock".
So many buyers ?

 

[Shaun]

Would an LM317-regulated PSU do?

This is possible, with provisions, as so well-documented on the site.

 

[es44]

You can also have a look here: http://www.diyaudio.com/forums/analogue-source/129126-simplistic-njfet-riaa.html
It's reasonable simple, yet with very good results.

Best regards
Ebbe

 

[Shaun]

You can also have a look here: http://www.diyaudio.com/forums/analogue-source/129126-simplistic-njfet-riaa.html
It's reasonable simple, yet with very good results.

Thanks. I'll have a look, though I don't necessarily need a simple circuit.

 

[cromodora]

Shaun the sheep,

You sniff at the last suggestion?
You think you are too good for a simple circuit.

I too was looking for a good phono cct a few years back..
But never in my wildest dream would I have the nerve to post a question like yours expecting to be spoonfed.

Pull out your thumb and start poring over the posts in the 'Analog Source' section. You will learn a lot along the way and you will know to narrow down what to ask.

 

[Shaun]

You sniff at the last suggestion?

That was not a sniff. I said I'd have a look. I think you also missed the gist of my original post. I asked for recommendations, and I'll consider them all. I thought, in my last post, that I should point out that it does not have to simple. I have nothing against simple, but I don't want contributions to the thread to be limited in terms of complexity or simplicity.

Furthermore, I'm not researching how to build a phono stage; I stated that I simply don't have the time to do a design from scratch, which I believe I am capable of. It is not that I don't care to do so but, rather, I have other interests that compete for my time, such as family and part-time studies.

I have no problem with asking people for their opinions, suggestions or recommendations. I think that what I did is a relatively efficient way of getting ideas: simply ask. People who want to help will help. Others have the right to comment, too...

 

[cromodora]

.

 

[cromodora]

Being spoonfed is the most efficient way to eat.
Just ask.
People who want to feed will feed you.
After all, you have no time while others have lots.

 

[Mooly]

The original question was very specific I thought 🙂

Further to me mentioning D Selfs design, it seems there are now PCB's and kits available.
Specifications are also given,
The Signal Transfer Company

 

[toufu]

What about VSPS and PhonoClone from Richard?

 

[peranders]

Nothing wrong to be spoonfed if the food is good.

Shaun, you also check Nationals phono based on their ultra high performance opamps.
http://www.national.com/an/AN/AN-1651.pdf

 

[Joachim Gerhard]

I made a simplified version of the Self circuit only for phono. I recently posted it on my MPP thread.