PULLING TWO POWER TUBES IN MY AD 30 HEAD?
Moderator: bclaire
-
- New Member
- Posts: 3
- Joined: Wed May 08, 2019 2:36 pm
PULLING TWO POWER TUBES IN MY AD 30 HEAD?
I did this in the past on mesa amps, marshalls, vht amps but I want to know with my ad30 head can I pull two tubes and what ones to pull as each amp manafture is different. I rememeber my old twin was 1 & 3 instead of say the two inner or two outer ones. Please let me know then of course my 16 orange cab would plus into the 8 ohm on amp. I want to make sure with orange as this amp is so good but I want to ask first, thanks
Re: PULLING TWO POWER TUBES IN MY AD 30 HEAD?
1+4, 2+3, 1+3, 2+4. As long as you have one in the left most pair, and one in the right most pair. But, you'll also need to change the bias resistors.
Last edited by Jondog on Wed May 08, 2019 4:40 pm, edited 1 time in total.
-
- New Member
- Posts: 3
- Joined: Wed May 08, 2019 2:36 pm
Re: PULLING TWO POWER TUBES IN MY AD 30 HEAD?
I emailed orange in USA and they said it wont operate doing this ? I think they are wrong. Also I cant get a hold of anyone in UK to ask. So two inner tubes is safe to pull the way you described it ?
Re: PULLING TWO POWER TUBES IN MY AD 30 HEAD?
Change the bias resistors. Orange likely won't tell you how to modify their amps in a way they were not designed.deanogeorgeproject wrote: ↑Wed May 08, 2019 4:05 pmI emailed orange in USA and they said it wont operate doing this ? I think they are wrong. Also I cant get a hold of anyone in UK to ask. So two inner tubes is safe to pull the way you described it ?
Re: PULLING TWO POWER TUBES IN MY AD 30 HEAD?
If you do some googling you will see this is not possible without modifying the amp's bias circuit as stated above
This is not like a jcm marshall or something where you can just pull two tubes and swap speaker outs. If you really want to do that, take it to an amp tech and have them modify it for you
This is not like a jcm marshall or something where you can just pull two tubes and swap speaker outs. If you really want to do that, take it to an amp tech and have them modify it for you
-
- Duke of Orange
- Posts: 9765
- Joined: Sat Jun 15, 2002 1:05 am
- Location: Amsterdam, Hollandland.nl
Re: PULLING TWO POWER TUBES IN MY AD 30 HEAD?
Big difference from most Mesa / Marshall / etc amps is that the AD30 is cathode biased, not fixed biased.
With fixed biased amps you can pull 2 (paired) output valves and just bumping the output (speaker) impedance one step keeps everything groovy.
With cathode biased amps, as mentioned, it isn't so simple...
Andy.
With fixed biased amps you can pull 2 (paired) output valves and just bumping the output (speaker) impedance one step keeps everything groovy.
With cathode biased amps, as mentioned, it isn't so simple...
Andy.
aNDyH.
Ever tried to outstare a mirror?
In the bathtub of history the truth is harder to hold than the soap, and much more difficult to find!
Ever tried to outstare a mirror?
In the bathtub of history the truth is harder to hold than the soap, and much more difficult to find!
-
- New Member
- Posts: 1
- Joined: Thu May 23, 2019 10:30 am
- Location: London
- Contact:
Re: PULLING TWO POWER TUBES IN MY AD 30 HEAD?
I am 100% interested to have this device
Who is online
Users browsing this forum: No registered users and 78 guests