Bitmo Mod Kit for AC4

[Billyboygretsch]

Has anyone installed this mod kit ? Or even tried/ heard it. Wonder whether it's worth doing or not. Not sure about these mod kits which seem to arriving on the market as never used one

[dave robinson]

I've just picked up an AC4tv and ordered the mod kit, I'll let you know how it sounds when it arrives.

[dave robinson]

Well the mod kit arrived yesterday and I have just finished fitting and testing it.
The AC 4 is a great little amp and it gives the old Shads sound in spades. First impressions are, this kit gives it a bit of versatility in that two more sounds are available which are as the advert describes, but having tried them I think the stock sound is fine for our needs and for Shadows people it's a waste of money. Sorry I'm not enthusiastic about it, but at least I've saved you all some dosh.

[Olsson]

Hi
I have made one modification, I have replaced the 12AX7 with a 12AY7. In my opinion it sounds better.

/Bertil

[dave robinson]

Hi Bertil, yes I agree with you on that, part of the Bitmo Mod is the replacement of the 12Ax7 for a 12AY7 and it does allow more headroom.
I've just been playing some more and can actually feel the benefit of the two other 'voices', although similar changes can be achieved using the guitar tone and volume controls to an extent. They do work there's no doubt, but whether most would be happy with the stock sound I suppose is down to opinion. It may grow on me but at a total layout of £32 I think many would say it's an unnecessary waste of money.
If you just wanted more headroom the 12AY7 in place of the 12Ax7 would be a cheaper mod.

[dave robinson]

My apologies folks, just checked that valve and it's a 12AT7 - not 12AY7. It seems that there may be a few different valves that fit and will make the amp do different noises.

[anniv 63]

Thanks for this initial report Dave.
I had seen this kit for the Vox ac15 c1/cc1 advertised and always wondered just what it might do,
I.E. primarily improve the voicing/clean sound on the top boost only channel on the earlier CC1 model
fitted with Wharefdale speaker.
Probably now as you say not worth this mod especially as I personally don't want a high gain tube screamer!!!

Mike

[dave robinson]

I don't think you would benefit from the mod on the AC15 Mike, last time I tried one of those I got a great Shads tone from it.

[dave robinson]

Just to add to that Mike, the best mod would be Roger Alcock's Vintage Unit with the EF86 if he does one for that amp. I fitted one to my Vox AC30 TBX, you would notice the difference there!

[anniv 63]

Thanks for the info Dave
I did contact Roger Alcock some time back about his Mod Kit, but he said he was busy at the time
and I guessed maybe he wasn't doing more kits of the EF 86 type?
Maybe I will give him a PM or possibly he might be reading this topic thread?

Mike