Express / Rocket
Moderators: pompeiisneaks, Colossal
-
- Posts: 20
- Joined: Fri Jul 07, 2017 3:54 am
Express / Rocket
Any thoughts on marrying a Express pre-amp section to a Rocket power section?
Re: Express / Rocket
Liverpool?Schmirleroo wrote: ↑Thu Nov 19, 2020 5:09 am Any thoughts on marrying a Express pre-amp section to a Rocket power section?
Best .. Ian
-
- Posts: 20
- Joined: Fri Jul 07, 2017 3:54 am
Re: Express / Rocket
Yes... except the power section I'm referring to is tube rectified and cathode biased..didit wrote: ↑Thu Nov 19, 2020 9:31 amLiverpool?Schmirleroo wrote: ↑Thu Nov 19, 2020 5:09 am Any thoughts on marrying a Express pre-amp section to a Rocket power section?
Best .. Ian
Re: Express / Rocket
But a Liverpool is cathode biased.Schmirleroo wrote: ↑Thu Nov 19, 2020 10:56 amYes... except the power section I'm referring to is tube rectified and cathode biased..didit wrote: ↑Thu Nov 19, 2020 9:31 amLiverpool?Schmirleroo wrote: ↑Thu Nov 19, 2020 5:09 am Any thoughts on marrying a Express pre-amp section to a Rocket power section?
Significant differences between Liverpool and Rocket power amp section are in the details of ---
- split cathode bias,
- values of various key resistors,
- and the choke before the screens,
- the nominal voltages derived upstream from the power supply,
Tube rectifiers are in broad strokes really no different than silicon rectifiers despite mythologies spread by certain evacuated mystics.
Best .. Ian
You do not have the required permissions to view the files attached to this post.
Last edited by didit on Sun Dec 13, 2020 5:28 pm, edited 1 time in total.
-
- Posts: 20
- Joined: Fri Jul 07, 2017 3:54 am
Re: Express / Rocket
Indeed it is sir...didit wrote: ↑Thu Nov 19, 2020 4:48 pmBut a Liverpool is cathode biased.Schmirleroo wrote: ↑Thu Nov 19, 2020 10:56 amYes... except the power section I'm referring to is tube rectified and cathode biased..
cathode bias.jpg
Significant differences between Liverpool and Rocket power amp section are in the details of ---To be strict, Rocket is missing a negative feedback loop too.
- split cathode bias,
- values of various key resistors,
- and the choke before the screens,
- the nominal voltages derived upstream from the power supply,
Tube rectifiers are in broad strokes really no different than silicon rectifiers despite mythologies spread by certain tube mystics.
Best .. Ian
R
Re: Express / Rocket
There is a bit more to it than that. The Liverpool also uses 1K screen resistors in lieu of 100 ohm. The 1K offers less bass response and does make sense with the Express style preamp.
The 1K choke resistor dials in the sag for the amp as opposed to using a choke.
The 1K choke resistor dials in the sag for the amp as opposed to using a choke.
Yours Sincerely
Mark Abbott
Mark Abbott
-
- Posts: 294
- Joined: Thu Jun 01, 2006 12:30 am
Re: Express / Rocket
why not build a liverpool with a SS rec / tube switch... bet you'll keep it on SS tho.