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Re: Vox - Wah V847A - the new one

Posted: 26 Jul 2008, 00:58
by Greg
soulsonic wrote: :shock:
Why they do that? How hard would it be to order one from an American seller and have it shipped? Do you guys have ridiculous import duties or something?
No, our import duties and laws are pretty fair. We don't pay any duty on personal goods under $1000.
I could buy these from the US.
Wah's are pretty haevy, so shipping is around $40 to $50 each, but still a lot cheaper than buying in Australia.

To be honest, I had no idea they were that cheap in the US.

Bajaman - has the drop in the US dollar helped the kiwi $ much ?
I'm sure the living style makes up for the economy right ?

Vox 847A mods?

Posted: 27 Sep 2008, 21:38
by BennyBoop
Hi, first post here, but I've been around for sometime just reading (and learning :wink:)

So, I read a little about potential mods on http://www.stinkfoot.se/andreas/diy/mods/voxnew.htm
and I'm planning on a true bypass mod.

Andreas states that some other mods may be doable but that it could be a little tricky due to the small sunface-mounted components on the back of the PCB.

My idea is to then remove the buffer-stage which he says could improve the sound a bit (reduce the harsh high end).

Do you think this is possible? Or do i have to track down an old Vox 847 with full size components and then make the mods?

Thanks /Ben

Re: Vox 847A mods?

Posted: 28 Sep 2008, 20:01
by Hanglow
I don't know about that particular one, but you could just make your own board out of perfboard, just use one of the many wah pcbs that are around as a guide. They are small and easy circuits to do. or get a pcb from someone here or from the likes of general guitar gadgets. :D

Re: Vox 847A mods?

Posted: 28 Sep 2008, 20:58
by BennyBoop
Would be an idea of course. Any special you would reccomend soundwise?

/Ben

Re: Vox 847A mods?

Posted: 28 Sep 2008, 22:50
by Hanglow
Best thing to do would just to tweak to get the sound you want, they all go from the same basic circuit, just with different values in some parts of the circuit. So if you were to get, for example, the general guitar gadgets board- you could build it to your own specs.

If you are a member arons diystompbox forum there is a good comparison chart you can look at here- for a lot of the different "classic" ones

I imagine this place also has some good threads here's one

Re: Vox - Wah V847A - the new one

Posted: 29 Sep 2008, 11:07
by modman
I merged this thread with an older one on the new Vox V847a.

The V847 was not true bypass but didn't have a buffer like the Dunlop Crybabies. Removing it from a Crybaby will slightly change your effects tone for the better, but making a Vox true bypass will only improve your bypass signal.
Like I said earlier, rip out the smd board and build in the original Vox circuit with correct values (check Fuzzcentral for layout files and schematicsheaven for the factory schematic), low gain metal cans and a decent inductor and you'll be in wah heaven. The only important thing left then, if to check whether your pot has a decent dead zone so you reach maximum treble (no resistance) BEFORE the end of the taper. If this isn't the case, your max treble point is where you click the switch.

Interested to know whether the pots on the V847a are any good... so do let me know if you get the change to measure them.

Re: Vox - Wah V847A - the new one

Posted: 01 Oct 2008, 22:26
by drmathprog
Well, it's been 35 years, but the one time I visited NZ I found it to be was the most beautiful country I had ever seen by a small bit, and it had the best lamb I ever tasted by a wide margin! :)

Re: Vox - Wah V847A - the new one

Posted: 05 Oct 2008, 19:29
by BennyBoop
modman wrote:I merged this thread with an older one on the new Vox V847a.

The V847 was not true bypass but didn't have a buffer like the Dunlop Crybabies. Removing it from a Crybaby will slightly change your effects tone for the better, but making a Vox true bypass will only improve your bypass signal.
Like I said earlier, rip out the smd board and build in the original Vox circuit with correct values (check Fuzzcentral for layout files and schematicsheaven for the factory schematic), low gain metal cans and a decent inductor and you'll be in wah heaven. The only important thing left then, if to check whether your pot has a decent dead zone so you reach maximum treble (no resistance) BEFORE the end of the taper. If this isn't the case, your max treble point is where you click the switch.

Interested to know whether the pots on the V847a are any good... so do let me know if you get the change to measure them.
Yes of course the TBP-mod will only change my bypass-signal. Okey, I'll see what comes out of this, have too many projects right now. Thanks! :)

Re: Vox - Wah V847A - the new one

Posted: 11 Oct 2008, 17:46
by Bside2234
I just got done taking out the guts on an 847A and replacing it with a 847 circuit. I etched my own board so I could use the 847A's dc jack. Came out really good. Here is a picture. I have a few more with it cleaned up a little more but they are still on my camera.

https://i69.photobucket.com/albums/i44/ ... G_0365.jpg

Re: Vox - Wah V847A - the new one

Posted: 12 Oct 2008, 18:52
by BennyBoop
Looks good. :thumbsup

Would be really nice with a schematic and layout....a project thread maybe? :wink:

Re: Vox - Wah V847A - the new one

Posted: 26 Jan 2009, 00:34
by Entrant_21
Sorry to be bumping an old thread, anyone got the schematic for this one? I'm modding one soon and a reference schematic would be handy!

Re: Vox - Wah V847A - the new one

Posted: 27 Jan 2009, 13:09
by DimebuGG
I had one of these and later replaced the board and components and changed everything..the stock is way too trebley at toe down and has a weak wah sound..it uses MPSA13 at the input buffer..