Page 1 of 1

Loss of power (volume) in my AD-30 Combo

Posted: Sat Nov 20, 2010 12:45 pm
by barrington
Hey again people, i had a problem with my AD-30 Combo last night, when i turned my amp on the power light came on but no signal was goin through it, i soon noticed my 12ax7 valve (furthest away from the el84) had fallen out, so i plugged the valve back in and i got my signal back, however it seems like the amp has lost power, i needed to push it to 3/4 to get the volume i would normall get at just less than half, do you think it could just need a change of valves or you think it needs looking at by my tech who will want the amp for about 2 weeks when its needed for gigs!!!
if anyone could give me any advice that would be great.
x
b

Re: Loss of power (volume) in my AD-30 Combo

Posted: Sat Nov 20, 2010 3:41 pm
by Randy Bass
I would start by replacing the preamp valve that dropped out. It would have taken a bit of an impact when hitting the bottom of the cab, so it may be damaged.

Re: Loss of power (volume) in my AD-30 Combo

Posted: Mon Nov 22, 2010 12:54 pm
by barrington
just took the back off my amp to have a look at the valves and it seems the connection on the far pre amp valve is quite loose, like as i put the valve in the connection, the connection pushes into the amp! so its quite difficult to get the valve to in properly. cant really tell if the amp works better yet as i need to hear it at rehearsals to tell if the volume has come back.

Re: Loss of power (volume) in my AD-30 Combo

Posted: Tue Nov 23, 2010 10:29 am
by a.hun
barrington wrote:just took the back off my amp to have a look at the valves and it seems the connection on the far pre amp valve is quite loose, like as i put the valve in the connection, the connection pushes into the amp! so its quite difficult to get the valve to in properly. cant really tell if the amp works better yet as i need to hear it at rehearsals to tell if the volume has come back.
If the valve base is loose that needs fixed by a tech. Don't risk trying to run it as is because there are high voltage connections to the valve base which may work loose as it moves and cause real danger to you and the amp.

Tech time!!!


Andy.

Re: Loss of power (volume) in my AD-30 Combo

Posted: Tue Nov 23, 2010 6:26 pm
by TheOrangeJuicer
a.hun wrote:
barrington wrote:just took the back off my amp to have a look at the valves and it seems the connection on the far pre amp valve is quite loose, like as i put the valve in the connection, the connection pushes into the amp! so its quite difficult to get the valve to in properly. cant really tell if the amp works better yet as i need to hear it at rehearsals to tell if the volume has come back.
If the valve base is loose that needs fixed by a tech. Don't risk trying to run it as is because there are high voltage connections to the valve base which may work loose as it moves and cause real danger to you and the amp.

Tech time!!!


Andy.
That would be if it were PCB mounted. If it's PTP, then the tube socket pin grips will move around a bit. He needs to be sure the tube pins are straight before inserting the tube. Also that he inserts it carefully to avoid forcing it in crooked in any case.

Re: Loss of power (volume) in my AD-30 Combo

Posted: Tue Nov 23, 2010 9:50 pm
by a.hun
TheOrangeJuicer wrote:
a.hun wrote:
barrington wrote:just took the back off my amp to have a look at the valves and it seems the connection on the far pre amp valve is quite loose, like as i put the valve in the connection, the connection pushes into the amp! so its quite difficult to get the valve to in properly. cant really tell if the amp works better yet as i need to hear it at rehearsals to tell if the volume has come back.
If the valve base is loose that needs fixed by a tech. Don't risk trying to run it as is because there are high voltage connections to the valve base which may work loose as it moves and cause real danger to you and the amp.

Tech time!!!


Andy.
That would be if it were PCB mounted. If it's PTP, then the tube socket pin grips will move around a bit. He needs to be sure the tube pins are straight before inserting the tube. Also that he inserts it carefully to avoid forcing it in crooked in any case.
AFAIK the AD30 valve bases were always board mounted. (Or were there some hand wired Custom Shop AD30s?)


Andy.

Re: Loss of power (volume) in my AD-30 Combo

Posted: Thu Nov 25, 2010 6:53 pm
by barrington
hey again chaps, used the amp at rehearsals last night and still not sounding as it should. should i try replacing the power valves aswell as the little ones? or just bite the bullet and take it to my tech?

Re: Loss of power (volume) in my AD-30 Combo

Posted: Thu Nov 25, 2010 10:42 pm
by a.hun
Ahem...
a.hun wrote:If the valve base is loose that needs fixed by a tech. Don't risk trying to run it as is because there are high voltage connections to the valve base which may work loose as it moves and cause real danger to you and the amp.

Tech time!!!


Andy.
Remains my advice...