• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

12b4 vs. aikido linestage

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Hi,

A remark from burnedfingers in the thread about the etude preamp lead me to this question: how does a deluxe version 12b4 cathode follower ( with very good power supply, components and possibly active load) compare with the aikido-breed of linestages? Can anyone second the forementioned verdict that the aikido is in another league than a 12b4 cathode follower(although burnedfingers took the rather basic etude as comparison material) or give his thoughts on this subject?

I've breadboarded a 12b4 some time ago with good quality components throughout and oversized dual mono tube rectified ps; it sounded good although I never owned another preamp to compare with, didn't need a pre for my e80cc/el84 set and was a little careless with too long cables and chitty cathode caps; my only bad findings were harsh highs and weak bass (both probably caused by the mentioned flaws). To give an idea of the circuit: 290v B+, 34mA current draw each channel // 500 ohms cathode Rs // 4,7k anode load // oversized coupling caps for the power amp following. I first tried the Etude working point but too much soldering in between to do a fair comparison.

I'ld greatly appreciate any comments that could push me towards a definite version of a 12b4 (hope it'll get some praise here versus the aikido; I've got all the components lying here + I can find inspiration for good 12b4 signal circuitry in the many posts in this forum) or an aikido if those are soooo much better....

Muchas gracias,

Simon :D
 
12B4 linestage

...try this ;-)
 

Attachments

  • jeschkeit-khv.jpeg
    jeschkeit-khv.jpeg
    43.7 KB · Views: 619
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.