How about that Vox AC30?

[adam32790]

What do you guys think about the ac30. I currently have a Hot Rod Deville, fender american deluxe strat and a ts808 tubescreamer and play blues. I really dig the drive on vox amps. How much better of a sound would I get with the vox in comparison to the hot rod setup i got right now?

[Robert M. Martinelli]

Well,
being a Vox enthusiast and collector maybe my opinion is a little "biased".

I have played ( or worked on ) many other makers' tube amps, but every time I switch on my 1964 AC30TB ( with silver alnicos ) I simply get blown away.
The normal channel is warm and smooth, it' s virtually impossible to overdrive it, the sound stays incredibly defined even at higher volumes, still round and full;the brilliant channel is astonishing, as the volume goes up the sound gently overdrives, but never obtrusively, and each note sings, the harmonic content is by far the richest I've ever heard. As to the output power, listening to a good AC30 makes it difficult to believe the thing has only 33 W, its presence and dynamic behavior putting it on par with 50W amps.

Another thing I like about my amp is the "respect" it shows for both the player and for each one of the different guitars I play through it.....It respects the player by letting your touch make a difference on every note, it respects the guitar because it lets every guitar show its true soul, be the guitar a Tele, a Strat, an SG - you name it, you can be sure it will sound great through it.

At least half of the AC30 legendary status comes from the AlNiCo Celestions
( blue or silver ), and listening to a couple of those in good working order is an unforgettable experience.

Bridging the input channels can be "seriously fun", as you can dial in the right amount of bigness from the "normal" channel and overdrive and high end from the "brilliant" one....

The only drawback is that AC30s from the 60s are getting rarer and more expensive by the hour, and later models are not THAT good, though some ( expensive ) reissues get closer to their older borthers.

Hope this helps

Best regards

Bob

[txstrat]

I used to own a 70s AC30 that was really worn out but played great. The sound was incredible and it sounded best when quite loud, like many other amps as well. Anyway, I sold it cause I was playing in a band doing covers of different styles and needed something with different sounds.
Today (the vox is 20 years ago) I prefer the sound of a cranked blackface fender amp for my own playing. I love the sounds of Rory Gallagher (Strat w/ Vox AC30), Buddy Guy (Strat w/ 59 Bassman), Jonny Lang (Tele w/ Fender Tonemaster ), and most of all Stevie Ray Vaughan (Strat w/ Fender Vibroverb, Super Reverb, Marshall or Dumble amps).
IMHO a Strat over the Hot Rod Deville is similar to that Buddy Guy sound and over the Vox it should sound similar to Rory Gallagher.
You should probably listen to some albums of these guitarists to compare the sounds and find out what you like more.

Matt

[adam32790]

Thanks guys you seem quite educated in this matter. I played one recently and just was amazed at the sound I got when I blended the two channels. I really love how class A amps work. The only problem I have is the reliability. I've talked to guys with ac30's (made in china) and some of them say they have worked great for them and some of them say they have tanked. It sounds like its the luck of the draw. I know I'm better off getting one made in england but can't quite afford that and like you said they are hard to come by. Any recommendations.
Thanks

[MattT]

Some of the reissues have a poorly designed standby switch that stresses the rectifier tube. Probably most of the reliability issues you've heard regarding rectifier tube failure are due to that. The solution is to leave the standby switch in the ON position and let the GZ34 rectifier bring the amp up slowly.

[adam32790]

Oh i see. Another reason i'm interested in the ac30 is because it has such a broad spectrum of sounds it can produce. I'm into the Stevie stuff but I am also interested in the Rory stuff too. Overall, just trying to find my own sound but was searching for an amp with more of a vintage distortion.

Tyler

[Daver]

Some of the reissues have a poorly designed standby switch that stresses the rectifier tube. Probably most of the reliability issues you've heard regarding rectifier tube failure are due to that. The solution is to leave the standby switch in the ON position and let the GZ34 rectifier bring the amp up slowly.

MattT
Could you elaborate on this? What specifically is bad about the switch or circuit? Thanks!
Dave

[Robert M. Martinelli]

Thanks guys you seem quite educated in this matter. I played one recently and just was amazed at the sound I got when I blended the two channels. I really love how class A amps work. The only problem I have is the reliability. I've talked to guys with ac30's (made in china) and some of them say they have worked great for them and some of them say they have tanked. It sounds like its the luck of the draw. I know I'm better off getting one made in england but can't quite afford that and like you said they are hard to come by. Any recommendations.
Thanks

Hi,
well, as I told you mixing channels is rewarding, you can get a lot of different nuances; as to the way AC30s work, well, I' m sorry for having to shatter once again this widespread belief, but AC30s are NOT class A but rather hot biased class AB1 amps. Not that it matters, just trust your ears, and simply search for the tone you like.....do you now like less the way AC30s sound just because now you know they work on a different principle? Who cares! Let your ear be the judge.


To me, AC30s production ended the day they moved production to China - Period.

My advice would be to find a late 60s specimen (67 to 69 ) with some cosmetic flaws but MANDATORILY with the speakers ( if original they' d be Silver AlNiCo ) in good shape; you can always repair the amp if something is wrong, and restore it cosmetically if you like ( or leave it the way it is if you like relics, think there is people paying for having someone "relicing" their guitars by chipping off paint and oxidize hardware.....). This way you' ll manage to get a good, hand-wired AC30 without killing your wallet, and working on it will only make you love for it grow greater and greater.
( BTW this is what I did when I fell in love with my 1964 TB ). It will be fun, and you' ll find all the help you need here at the forum.

Hope this helps

Best regards

Bob

[HTH]

If the rectifiers are failing using the standby switch, it sounds like the first lot of filter caps may be too large (or not rated high enough to cope with peak voltages???).

I installed a Mercury Magnetics RS output transformer for a friend on one of those Chinese-made AC30s. It sounded pretty average before the OT change, but spectacular after the OT change. Probably not so much 100% classic AC30 tone, but much more versatile. Oh, and I added a Weber copper cap to replace the GZ34, there'll be no rectos failing if I have my say (ha ha).

If I was looking for a gigging AC30, I'd get a AC30CC and mod it.

However, as the owner of a copper-panel non-TB AC30 with alnico blues, I will say that the old amps are something special, but limited in their versatility without resorting to pedals.

[MattT]

Could you elaborate on this? What specifically is bad about the switch or circuit? Thanks!
Dave

It's the way the circuit is. When you flip the SB switch there is too much current. The SB switch is in series with the HT center tap so when you flip the SB to ON all the filters start to charge simultaneously. If they allowed the first bank of filters to charge while in SB then it wouldn't be a problem. But the amp has a soft-start rectifier so just leave the SB switch ON and only use the power switch.

[Robert M. Martinelli]

I installed a Mercury Magnetics RS output transformer for a friend on one of those Chinese-made AC30s. It sounded pretty average before the OT change, but spectacular after the OT change. Probably not so much 100% classic AC30 tone, but much more versatile. Oh, and I added a Weber copper cap to replace the GZ34, there'll be no rectos failing if I have my say (ha ha).

If I was looking for a gigging AC30, I'd get a AC30CC and mod it.

However, as the owner of a copper-panel non-TB AC30 with alnico blues, I will say that the old amps are something special, but limited in their versatility without resorting to pedals.

Hi HTH,
Does the Weber copper cap raise the +HT voltage some? The GZ34 sets the +HT at 320VDC on "normal" AC30s, I expect the voltages to be a little higher with SS rectifiers...I built a small gizmo, an octal tube socket with a couple of silicon diodes at the right pins to substitute the GZ34 - When I want the amp to "sag" I leave the GZ34 on, when I want more dynamics I drop in the diodes/socket assembly in its place and set the voltage selector at 245V, to keep the +HT at 320VDC. The heaters run a little cooler (6,0 vs 6,4 VAC ) but that's all....

Congratulations for your copper-panel non-TB AC30 with AlNiCo blues!

As to versatility, I find that a good AC30 with inputs jumpering/blending can cover almost everything, except maybe heavy metal ( but I nonetheless do get some truly spectacular metal tones with my good' ol Digitech 2101 connected to it and blending channels, I also play Gambale, Satriani, Vai, Lane with this setup and, according to the listeners, the sound is pretty close to the originals - the 2101 is still a great piece of gear IMHO ).

Best regards

Bob

[soundmasterg]

The Weber Copper Cap is a solid state plug-in module that emulates the sag and voltage drop of the tube rectifier using diodes, resistors, and a varistor or something like that. They drop about 17v at idle, and sound VERY close to the tube rectifier. A very good value.

I've got a 1993 Korg (made in England) AC30TBX reissue that I've had since new. It sounds fantastic with the Celestion Blues, and I've compared it to a 1964 AC30 TB with original speakers. The '64 amp was a 10/10 and mine was a 8/10. For the price the owner and I would both have picked mine. The new CC amps can be quite good too, though they are harder to work on in some ways. The most important thing is the speakers.

Greg

[Robmosis]

New ac30cc owner

I know this is far from the last dated post but I figured maybe my opinion would help your decision if not made yet. I have been playing guitar for about 20 yrs now and have switched to tube amps about 4 yrs ago. I was one who fell for the drawbacks of tube amps that you hear and was on the endless search for the perfect ss amp. Needless to say it was a 16 yr useless effort. A tube amp is the greatest blessing to any tone concerned musician.
But back to the AC30cc. I am by no means a vintage expert, I have played 2 vintage ac30's and fell in love with them immediately. I have also played many vintage marshalls, Fenders, and so on.(My best advice is play everything you can even if your not looking, you will learn so much about what tone you like) I have never found a better sound than an AC30.(IMHO)
Since money is an issue for my purchases I could not fork out for a vintage or Englund made Vox so the chinese CC was really my best bet. I was pretty weary with all of the horror stories I heard about the chinese made AC30's, so I found this forum, bought books and began to learn as much as I could about what makes a tube amp sing. Now, I am no were near a amp tech but I believe I have a good idea about how stuff works now.
What I guess I should just say is go and buy the AC30CC. I did and though I have not owned it very long I am soooooo very happy with it. Taking the back off and looking at it you can see that they really tried to stay as close to the simple is better design that has made the AC30 legendary. The new features just add to this great amp without taking away anything. I won't say that it sounds like one from the 60's but no new amp will and lets face it, its pretty darn close. The biggest reason is the basic design has not changed. This amp is worth every penny in tone. I do think they chimped out on the small stuff like plastic jacks and switches. But run it hot, in vintage mode, (blending the channels is pretty sweet)and you will not be disappointed. It seems there may have been a bad batch out there but if you educate yourself about how it works your worries will be diminished.
Peace and Great Tone to all, Rob

[Steve A.]

... What I guess I should just say is go and buy the AC30CC. I did and though I have not owned it very long I am soooooo very happy with it. Taking the back off and looking at it you can see that they really tried to stay as close to the simple is better design that has made the AC30 legendary. The new features just add to this great amp without taking away anything. I won't say that it sounds like one from the 60's but no new amp will and lets face it, its pretty darn close. The biggest reason is the basic design has not changed. This amp is worth every penny in tone. I do think they chimped out on the small stuff like plastic jacks and switches. But run it hot, in vintage mode, (blending the channels is pretty sweet)and you will not be disappointed. It seems there may have been a bad batch out there but if you educate yourself about how it works your worries will be diminished.
Peace and Great Tone to all, Rob

Rob:

Another option is the handwired AC30HW that they put out in 2007. There is an EF86 channel along with a regular Top Boost channel that you would expect in a Vox. I believe it comes with Vox-branded Celestion Blues. As I recall the Chinese AC30 came with your choice of Celestion Blues or the cheaper Vox speakers.

I believe that the schematic is similar to the AC15HW (which is the one that has me drooling- the AC30 weighs something like 80 pounds!):

http://www.blueguitar.org/new/schem/..._handwired.pdf

I'm planning to build the EF86 half of the amp in an Epiphone Valve Junior head... woohoo!

Steve Ahola

EDIT There are evidently at least 2 different AC30HW's that were made- the one I looked at recently at a local music store had the EF86 and Top Boost channel- but no reverb or tremelo. This one is selling new for around $1800 or $1900. There is an older one with a single Top Boost channel and reverb and tremelo which sold for ~$2800.

I also see that a company called JMJ is making a JMJ-30 head amp (but they are not currently taking any new orders ) The JMJ has 3 channels- the "Brilliant" channel with the EF86, the Normal channel and the Top Boost channel- no reverb or tremelo. Plus a power scaling control from London Power... retails for $1725 if you could buy one.

[theunrulychef]

Steve, thanks for posting that schematic! I've been looking through every ac30 schematic I could find all week looking to do something like the handwired EF86 / Top Boost combo & the closest thing I could find was the Weber 6D30. I missed that AC15 handwired schematic. This really fills in the blanks.

Now to finish those taxes so I can get my refund & buy some more iron & glass.

Thanks,
Jay in Philly