Temporary Phono Preamp

[davidlzimmer]

Can I take an EQ with lots of gain and input the turntable in either the tape or line input and set the controls to simulate an RIAA curve until I build a phono pre?

The reason I ask, instead of just doing, is the EQ is 2 hours away.

Thanks,

 

[anatech]

Hi David,
It's better than nothing. Whether it's useable or not is another question. I would expect a great deal of noise and hum.

Radio Shack used to sell a really inexpensive preamp powered by a 9 V battery. That would work much better than the EQ idea. If you can build a circuit, you could make a temporary unit too. The RS unit is cheaper when you are done.

-Chris

 

[davidlzimmer]

I suspect you have a better idea. I have two urges. One to go back to analog (an antique dealer freind of mine told me I could sample his 500+ LP collection) and another to build a tube project.

I think what I will do is get my present projects completed, then build a little 12AX7 phono pre. If I buy a cheap one first, it might just stay that way.

Thanks for bringing me back down to earth Anatech!

 

[sreten]

Can I take an EQ with lots of gain and input the turntable in either the tape or line input and set the controls to simulate an RIAA curve until I build a phono pre?

The reason I ask, instead of just doing, is the EQ is 2 hours away.

Thanks,

Hi,

It would work in a fashion, but one of your problems would be incorrect
cartridge loading. Another would be most EQ's don't have enough range.

/sreten.

 

[anatech]

Hi David,
Good luck and keep building!

Since you like tubes, get a copy of the Radiotron Designers Handbook, Rev4 (electronic or real). Another great book is Morgan Jones "Valve Amplifiers", available at Amazon.com.

After reading some of RDH4 and Valve Amplifiers, you'll have a much better idea on how to go about designing a good preamp.

-Chris

 

[davidlzimmer]

Thanks folks.

I need some brushing up for sure but, tubes are my old freinds. Built my first project in 59. A 3 tube reciever. Beat the c.r.a.p out of my crystal set!

 

[anatech]

Hi David,
I was born in 1959. I missed all the instruction on tubes that was available to you. You may have old magasines and text books that have most of this info in it.

The Morgan Jones book is a modern look at how to use these devices, with modern semiconductors thrown in to allow some extra tricks. Worth a read or three!

-Chris

 

[davidlzimmer]

Kids!

 

[phn]

I'm not going to debate which is better, tubes or chips, any more than I'm going to debate who's stronger, Hulk or Superman. But it's a good idea to make a simple chip phono preamp to use as a reality check. The chip pre is cheap, easy to make and sounds surprisingly good. The tube pre is supposed to outperform it.

 

[davidlzimmer]

Tempting. Very tempting.