building a vox amp .... where should i start?

[arielfx]

after building several stomp boxes i think i would like to try something new for a change.

i don't have great electrical know-how but i get along pretty well just the way it is because i can read schmatics...

i am very interested in building a vox ac30 TB clone with the cabinet and all... i am pretty handy with wood so i think i won't have too much trouble there but i don't really know where to start as in researching this amp.

i didn't find a good readable schematic or layout for this amp online and i don't know what parts are used and couldn't find some photos of the cabinet construction.
i think these espects are very important because i need to see how the original looks like / built so i can think of anything to change but i am not sure i can do everything better, i am pretty sure those guys from vox know a thing or two that i don't.

so if anyone could help me out on this i will appreciate it!

[idlefaction]

http://www.schematicheaven.com/  for the schem...
http://www.ax84.com for the people to help.  

http://www.hoffmanamps.com/boardkitmakers.htm for a place to get a whole ac30 kitset;
http://www.ultratoneamps.com/boardkits/voxac30_kit/ac30_lay.html for a concrete example of a layout.

hth!  

[gtrmac]

I've built two amps so far and although I would love to have a Vox I chose a Fender Tweed Deluxe and a Marshall 18 watt model 1958 as my first projects. The reason I haven't attempted a Vox yet is because it is one of the most complex designs out there and could be very challenging ( and Expensive!). If you decide to build one I would recommend getting a chassis from Weber VST and transformers from Mercury Magnetics. The transformers are important of course because they are very much a part of the sound of an amp. Mercury seems to have a very good reputation among DIY amp builders.

I also suggest that you have a look at //www.18watt.com You can get a very nice kit or a chassis and transformer set from GDS Amplification, one of the sponsors there. I got a chassis/trannie set and bought all the parts myself and I'm very happy with the amp.

Good luck![/code]

[idlefaction]

i'm lucky enough to live 45 minutes drive from Simcha Delft, so i get my transformers from him - i recommend those if you can afford them.  they're expensive though.

http://www.obsoleteelectronics.com/

if you can live without tremoplo, the project is a zillion times easier, also.  

[Jim Jones]

Hey Darren,

Well it looks like you're better off than all of us when it comes to sourcing great sounding iron!    Good job!  Hope Simcha is doing well these days.

Take care!

Jim

[R.G.]

I'm dabbling with making myself an AC30 replica. I posted some dimensions for an AC30 cabinet replica on GEO (for those of you who are not GEO-watchers), and will be completing it in the next little bit. A fellow who has just completed a **SLICK** AC30 replica cab is checking my dimensions and adding the finishing bits he did so the replicas can come out nice.

I got an AC30 replica chassis from Stephen Giles. Weber (speakers, not Gerald of Kendrick amps) has an AC30 chassis replica for about $100 - a good deal, considering it's a two piece chassis.

[arielfx]

i just checked it!

these look great, very helpful!
i usually do enter your site because you know that the stuff there is a must to read  :lol:  (even if I do not understand 100% of it).


thanks!

[Mike Nichting]

Mercury Magnetics is the place to go if you need an out of date transformer as they will custom wind one for you. They have the specs on many amp trannies.
Good people too. They have a solid reputation for great sounding trannies.

good luck,
Mike N.

[arielfx]

I think I got more questions now than answers!

There are alot of places that does custom transformers but how will I know from who to buy? Or maybe all of them are pretty good so it doesn't really matter?

I am also wondering about a cheap source for the "blue" speaker, I've noticed these are damn expensive and I am not sure that there ate no clones of it that do sound better and maybe are cheaper because it's obviosly overpriced because it was used in Vox amps.

One more thing.... anyone knows if these kits come with original spec. electronics? Will it sound close enough?

I know these questions seem to give the impresion I want everything to by served to me on a "gold plate"but I'm really the kind of guy that buys a million things and tests them and decides for myself but this time I am afraid the project is far too expensive to allow me to buy several speakers or transformers or anything else for that matter so I think I will trust the good people of this forum in what I buy - the makers who gets most of the raves will be good for me.

[Nasse]

If you are in doubt you can buy replacement transformers and choke from Vox, they should meet the spec. They say they are not like old 60s originals, but it is illegal to do transformers like they did...these electrical safety rules you know...or that is just urban legend or bullshit, anyway Vox has been made by trannies of several different make, so variation *IS* unpredictable.

A popular way to get started has been to do AC15 clone instead of AC30, but I doubt it is not much easier task. AC15 sound quality is just as good as AC30, and may be perfect if you need small studio combo. There is around some Matchless schematics  which is modernised copy of this. Does anybody know if you can use Fender Deluxe output transformer for AC15???

I was interested about building a vox and asked info from a guru and he answered that transformers, filter choke and pwr supply caps and alnico speakers are essential and important for *that* sound. I once played through Vox with my monster ceramic speakers, and they sounded ok for rhytm work but they say Celestion Blues are the best, period. If you play very very loud onstage, you may prefer Greenbacks or other ceramics and even solid state rectifier (a special transformer for that is available). In U.K there is a firm named EFTP who makes custom amps for Hank B Marvin, the man who has recorded more top hits with Vox AC15 and 30 than anybody, and EFTP KCP says in the ad that it is loaded with Jensens, which are somewhat cheaper than Celestion Blues, so who knows...We have this popular band Agents in Finland, and the guitarist is Vox fanatic, and I remeber have reading that they one time may have used Italian Fane "blue" speakers as replacement. Thanks to their roadies you can not find any old Voxes anywhere here, they have collected them all...

http://www.eftp.co.uk/page4.html
http://www.eftp.co.uk/page5.html

Good idea in KCP is a separate and big box for amp head, helps cooling

[arielfx]

Actually I know that company...

I have a client that is a Hank Marvin fanatic and we are trying to fix him with a modified quadreverb unit but it's not easy to find them in Israel.
He has tons and tons of Hank Marvin style gear and custom guitar made by Sechter (I think) with Kinman pickups and everything - He is crazy. I don't want to tell him about the amp because it's around 3200 Euros and I would hate to see him sell one of his guitars for it because he might just do that.

back to the Vox clone project...
I wanted to ask anoter thing that I forgot about!
The kit comes with all the electronic components but I wonder what did they use in the old Vox amps?
There are many kinds of resistors and capacitors available from www.angela.com and other sites, do you think I would have to change some parts to get it more "close to the original"?

I am sorry for having all these questions but I just can't seem to find any written information about this amp.