Home
AudioAsylum Trader
Tube DIY Asylum

Do It Yourself (DIY) paradise for tube and SET project builders.

For Sale Ads

FAQ / News

 

Use this form to submit comments directly to the Asylum moderators for this forum. We're particularly interested in truly outstanding posts that might be added to our FAQs.

You may also use this form to provide feedback or to call attention to messages that may be in violation of our content rules.

You must login to use this feature.

Inmate Login


Login to access features only available to registered Asylum Inmates.
    By default, logging in will set a session cookie that disappears when you close your browser. Clicking on the 'Remember my Moniker & Password' below will cause a permanent 'Login Cookie' to be set.

Moniker/Username:

The Name that you picked or by default, your email.
Forgot Moniker?

 
 

Examples "Rapper", "Bob W", "joe@aol.com".

Password:    

Forgot Password?

 Remember my Moniker & Password ( What's this?)

If you don't have an Asylum Account, you can create one by clicking Here.

Our privacy policy can be reviewed by clicking Here.

Inmate Comments

From:  
Your Email:  
Subject:  

Message Comments

   

Original Message

Re: RIAA design dilemma, need your opinions.

Posted by Kurt Strain on February 19, 2002 at 13:20:45:

Despite my daft idea for using the large coupling cap before the RIAA network, I think it works fantastic. See the schematic below for my phono stage design, then replace things as follows:

* Change bipolar CCS with new MOSFET CCS in http://www.sonic.net/~ktstrain/MOSCCS.jpg

* Change V1 to 6ER5, also change its cathode resistor where you want the plate voltage and current to be (I chose 90V and 2.5mA for Vp and Ip) and remove the cathode bypass cap entirely.

* Change V2 to 6GK5, change the cathode resistor again for your desired operating point (I chose 110V and 2.5mA) and remove the cathode bypass again.

* Change the first coupling cap to two 0.22uF TRT teflon caps in parallel.

* Change the 0.01uF cap in the RIAA to a TRT teflon.

* Change the 0.22uF output cap to TRT teflon.

* Change all resistors in the RIAA to Caddock TF020 film. Change cathode resistors to Caddock MK132.

This is a MM input phono preamp. Use a high quality MC step-up transformer for MC input. I never heard tube or transistor do as good a job as my EAR MC-3 for this function - zero noise, great sound.


That's what I use. I think it's totally first rate. Better than anything else I have heard. But's it's an expensive setup with those parts.

Kurt