Vox Ac30 Top Boost Questions and other thoughts

[lefxatz]

Hello to everyone. (I love this Forum!)
Well my name is Lef and this my first thread.
I own this great amp and have some questions. I think many of you can help me.


1) The cut pot is not responding well. When i turn it all the way up it cuts all bass & treble but in the 0-9.9 positions is not changing any sound... What can i do?
2) Should i change the speakers to anything newer ? alnico blue for example.


3) Can i find the date of this amp ? The serial No. is 25606.
4) Some tubes are Fender and some EH. Should i change them to matched ?
5) What are these blue caps ? Shouldn't have some other ? I have seen many pictures of other AC30's and they had some other metallic. The amp didn't work when i bought it and i gave it to a very good technician. He made it speak very good.


6) What is this supposed to mean ? "Jenny" name of the amp maybe ?


7) How can i remove the Cloth and clean it ? I don't want to try without any help because i maybe ruin something...

8) Needs some good cleaning from the inside. What can i use ?




Sorry for the amount of questions but i know that many of you have this amp and if anyone helped me would be very nice.
This are the pictures of the amp. Any other suggestions of modding this amp would be great...
Sorry for my bad English.
Thanks a lot again guys and looking forward to your opinions...
Lef.

[drlowlow]

I am not going to answer all the questions but I can give you an answer for some of them.
#2, change them if you don't like the way that the current ones sound. Its a subjective thing. the old ones might be in a bit of disrepair and if it was my amp I would unscrew them to make sure they in good working order.

#3, look online for date codes for vox. another solution is to look for date codes on the pots and other components. can usually find a cross reference for certain component manufactures.

#4, the only tubes that most people would worry about if they are matched or not would be the EL84s. This again is a subjective thing as some people think that mismatched power tubes give more enjoyable distortion. If the power tubes are matched and all the tubes are still good I wouldn't mess with it as long as you enjoy the sound.

#7, I wouldn't remove the cloth, I would take the speakers and the chassis out of the cabinet and I would clean it with a bit of light soap and a brush (not stiff bristles)

[lefxatz]

Originally Posted by drlowlow

I am not going to answer all the questions but I can give you an answer for some of them.
#2, change them if you don't like the way that the current ones sound. Its a subjective thing. the old ones might be in a bit of disrepair and if it was my amp I would unscrew them to make sure they in good working order.

#3, look online for date codes for vox. another solution is to look for date codes on the pots and other components. can usually find a cross reference for certain component manufactures.

#4, the only tubes that most people would worry about if they are matched or not would be the EL84s. This again is a subjective thing as some people think that mismatched power tubes give more enjoyable distortion. If the power tubes are matched and all the tubes are still good I wouldn't mess with it as long as you enjoy the sound.

#7, I wouldn't remove the cloth, I would take the speakers and the chassis out of the cabinet and I would clean it with a bit of light soap and a brush (not stiff bristles)

thanks man for your help. I will try removing the speakers. and i hope i find the date of the amp.

[HTH]

those alnico silver Celestions are highly sought after and are at least 50% of an AC30's tone imo. if they are in good working order then don't replace them, certainly not with modern alnico blues which are fine speakers, but not as nice as the vintage set you have.

with the cut control, I've seen various pot and cap values used over the years - what value pot and cap is in your amp? could also try replacing the cap, could be leaky.

in terms of date, the grey panel, silver alnico Celestions and logo would place it in the '64 - '67 range imo.

see if you can get the date codes off the speaker frames, that will help you date the amp fairly accurately. on those older celestions the date code might be on the cork gasket between the speaker and baffle.

[lefxatz]

Thanks all for your priceless help! About the silver Celestions i will see the date codes tomorrow as the value of cut pot and cap. Thanks again!

[Wakculloch]

Questions 4&5.
If you believe a matched set will make an improvement then give it a try. It'll probably lower hum levels and sound different, but not necessarily better.
They look like standard coupling caps sold by RS as spares, so they've probly been changed, but are good quality, so as long as theyre not leaky best left alone.

[Robert M. Martinelli]

Hi,

for heaven' s sake, keep that lovely amp as original as possible! The silver alnico bulldogs in your amp are probably the most precious and best sounding guitar speakers of all times! ( together with the previous original "blue" ones, differing only in the color, as Vox was not willing to pay to Celestion the extra 5 pounds per speaker for the painting job ). The current blues alnico are only reissues, you have the originals, so keep 'em as long as you can!

I am a collector who owns several Vox amps, and willing to help you, but to better answer your questions, I would need some other shots showing the control panel and its color, the handles, the vent ports, the voltage selector and so on - all these features help dating the amp . You should also take a look to the back cover, and you should have a plate saying "VOX AMPLIFIER" with model and amp S/N on it - take a close shot of it...if it has two lines the amp is a pre-1967 one, if it has three lines is should be a 67-68 ( pre 70, anyway, as in 1970 STOLEC, who owned Vox at that time, started to use PCBs and replaced the GZ34 with silicon diodes to cut down costs ). Inside the chassis, close to the power cord, under the mains switch and the fuse, you should also find the chassis S/N, unfortunately, this is not helpful to date the amp as the Vox premises were destroyed by a fire in 1967 and all the production records were subsequently lost. Keep also in mind that silver alnicos were phased out in the late 60s due to cobalt price increasing....

Looking at the pics you posted, your amp should be a post-1964 model, but I can' t say for sure without the views I asked, the name inside could be the name of the wirewoman who put the amp together back then....

Hope this helps

Best regards

Bob

[Robert M. Martinelli]

Hi,
sorry, I didn' t look all the pics, I now see your amp has a grey panel, rotating voltage selector, double row vents, metal power switch ( though this could be a later replacement, but it matches with the other features, so.... ) so it is definitely a late 60s model, a '68/69 IMHO, but.....Vox history is very complex, there have been several changes of ownership, so I beg your pardon if my statement is not so precise, but the exact age is very difficult to pinpoint.
Best regards
Bob

[buckshot]

G'day, That amp is identical to mine. My serial no. is 22789 and was built in late '66. It is one owner and I have just bought it from my mate who bought it new . He ardered it in 66 and received it in 67. He lived on an island. Note the different vox name badge from the usual gold ones. Your 3 vents on top should be grey metal( originally painted black). Hope this helps.
regards
Buckshot

[Robert M. Martinelli]

Hi again,
Vox started to use that kind of badge ( mainly on models intended for the US market ) at about the time Thomas Organ made an agreement with Tom Jennings, it would be good to have a clear shot of the rear panel, to see the S/N and the badge lettering, anyway, if the S/N is close to the one Buckshot kindly provided and the model and S/N are shown on a two-lined badge the amp is a pre-1967 or a 1967 one, if the S/N is lower and all the other mentioned features match, it could be a 1965-66 One.

( I have a 1964-65 TB which serial is in the low 20000s, so, if your S/N is within this and Buckshot's you can be reasonably sure your amp is a 1966 one ).

Anyway, keep also in mind that the "outer" S/N is different from the "inner" one ( the one on the chassis ) because the chassis was built by a contractor at that time, and Vox put the external S/N on when assembling the amp.

if the badge is a three-lined one ( and the amp is not a Jennings ) the amp is "younger", as already stated it could be a 1968-69* one.

*Note - silver AlNiCos were phased out in favor of ceramic speakers earlier than that, but Vox had some "leftovers" and so a small batch of AC30 was built using these instead of the then standard ceramic speakers.

Hope this helps

Best regards

Bob

[buckshot]

Ill send some pics of mine if you want. Email me at yogi4@optusnet.com.au if you would like to see it.
regards
Buckshot

[buckshot]

lefxatz

I have just found the original tag that came with mine when purchased new. As I said before yours is identical to mine. Mine was taged and inspected on 8th Dec 1967 so yours will more than likely be a late 67 as well.
regards
Buckshot