preamp kit?

[R-Carpenter]

Hi guys. I've been building speakers for a few years and now I am wandering if I can build a nice preamp. I would like to start with a kit that requires minimum tools. Possibly a tube kit (for esthetic's reasons). Any suggestions? I am capable of some metalwork and an expert in woodworking.
Thanks.

[AndrewT]

foreplay

[Original Burnedfingers]

Check thru the Aikido threads. Its an easy line stage to build and it offers superior performance over most kits.

http://glass-ware.stores.yahoo.net/newhardware.html

[AndrewT]

found it
http://www.bottlehead.com/et/adobesp..._stage_kit.htm

[Eli Duttman]

Not so fast, if you please! The power amp and source(s) that will be used impact GREATLY on the choice being made. If a power amp that requires less than 2 V. of drive to reach full power O/P is used in combination with a CDP, the very last thing needed is the gain both a Foreplay and an Aikido provide.

Mr. Carpenter, please tell us what sort of equipment you are going to use in combination with the line stage. Only then, can a good recommendation be made.

BTW, which section of Brooklyn is home? FWIW, I originate from East Flatbush.

[R-Carpenter]

I am in Brooklyn Navy Yard.
Mostly use solid state such as Bryston. Have AVA Fet Valve 550 at home (which is where preamp would go). I use Behringer 500 for all the speaker testing.
CDP: SONY ES, ROTEL, MRANTZ

[Eli Duttman]

Commercial CDPs, like those in your possession, can drive the IHF 10 KOhm "standard" load. That allows you to "breadboard" an inexpensive passive setup to test the drive voltage requirements. A pair of low cost 10 KOhm audio taper Carbon pots., from either Mouser or "Rat Shack", are what you need. The ends of the controls get connected to the source "hot" and ground. The wipers drive the power amp "hots". The grounds in each channel are common to CDP, control, and power amp. Keep the wiring between the controls and power amp short or you will get HF rolloff.

If you get satisfactory control over the listening level using the temporary passive setup, you don't need gain in the line stage you build. OTOH, if you find yourself fully advancing the pots. and still not satisfied, a design with gain, like those previously suggested, is in order.

Get the ducks lined up, before you spend hard earned cash.

[Original Burnedfingers]

Eli,

With all due respect I do differ in my opinion on gain. With the invention of the volume control was does have the option to adjust the level to suit ones needs. I always hear about too much gain out of a particular line stage but I don't agree because its never caused me a problem.

I have gone the volume control route from the CD player to the amplifier and found it to be ok. It works but I don't find it to be superior but then again its less costly. Depending on ones taste a set of decent pots usually sets me back about $50 and around $200 for stepped controls as I favor individual level controls.

You are correct as Mr. Carpenter could get buy with a Radio Shack dual pot and probably be happy. I felt that he was wanting something in the way of a project and that is what prompted me to suggest the Aikido.

Having built a number of Aikido's and other line stages of interest in the past 6 years or so I felt it was a superior piece demanding ample consideration. I will however acknowledge your considerable experience and knowledge in the field and bow out.

[chrish]

Don't want to get in the middle of a war here , but I thought Eli was just asking Mr Carpenter to perform a simple experiment to work out how much gain is required before recommending an option/opinion on pre amp. I don't think he was suggesting he use a rat shack pot as a replacement for a pre-amp.

[R-Carpenter]

My Sony ES CDP has variable out and a 2v outputs, so I've been driving the Amplifier with Variable out and gotten away with it pretty good. Now I want to see if by replacing “el cheapo “ output stage of the CDP with a tube preamp would improve things. Plus, I just want to make one for the hell of it. As Fingers said, “ I want the project” and he's quite rite.
I like the warm glow of tubes on a cold winter night.