diyAudio (
-   Tubes / Valves (
-   -   regaring 833se (

wasibi 30th March 2005 10:22 AM

regaring 833se
Anybody there bro have any 300b drive the 833 se circuit diagram to share,thanks:bigeyes: :bigeyes:

georgehifi 30th March 2005 10:01 PM

2 Attachment(s)
Not exactly what you asked for but close. 805 is similar, a step down in power. But gets driven by 300b. (input tube (13d3) b+ is 200v not 388v. typo) and pre driver is now 12bh7. The way this is set up i get 10mv peak to peak of noise/hum at the spearker terminals, very good low noise for a SET.

Cheers George

garbage 31st March 2005 06:27 AM

nice to see someone attempting insane voltages. ;)

i thought of doing the same, but the highish idle wattage puts me off. especially in sunny singapore.

here's a thread on this forum that is a good read if you decide to build this amp.

happy diying.

ReinoutdV 1st April 2005 06:50 AM

300B - 833
2 Attachment(s)
Hello Wasibi,

as "Garbage" correctly noted: these triodes do get warm. Last winter when i listened....the central heating was not switched on. The amplifiers did that job as well..... And i live in chilly-and-wet Netherlands.

Nevertheless these 833's do give a wonderfull sound. Never overpowering or dominant, but just everything perfectly in order. And the bass is that authorative; never heared that even with the real transistor beasts from Krell or Mark Levinson.

Your question regarding the 300B-833 connection. I use a 4:1 stepdown interstage to get a lowish impendance (833 wants that) and enough feeding power (the 833 needs that).
It's the same reason why Wavac uses a triode connected penthode: to get low impendance !
It works great and there are variations to this theme like using a 6C33C (already a low impendance) for a hgher quality interstage (lower ratio).

And how you use the 300b (what voltage) and how you drive that tube is completely up to you !
The essence is that 300B to 833 is possible using a stepdown interstage.

Lots of building pleasure.


georgehifi 2nd April 2005 06:07 AM

Remember always work on theses big triodes with one hand tied firmly behind your back, so your not tempted to use both, this 833 WILL FULLY KILL YOU, where as the 805 WILL ONLY HALF KILL YOU.

Cheers George

All times are GMT. The time now is 07:56 AM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 18.75%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio