Can you Help me out with this one...

I have only just put my recently acquired Thunder I-A into a playing condition and when I have come to try it out, I find that the Pre-Amp doesn't seem to be working. Having had no previous experience with one of these guitars, I am unsure as what is supposed to happen when I flick the Pre-Amp Equaliser Switch. When switched down the guitar works in passive mode and in the up position, the guitar is dead. Is this right? How would I know if the pre-amp was functioning or not for sure?

Martin.

I'll make the assumption that the boost circuit on a Thunder is the same as my Vantage VA900 - 2 x 9V batteries which does NOT make it an 18V circuit; one of those batteries runs the little red LED only!!
1. Obvious I know, but are the batteries in good nick?? It needs good batteries and if you leave a lead in the jack socket, you will flatten the batteries over the course of a gig, they are that hungry!
2. No loose leads or dry connections in the rats nest they call the control recess...

You'll know when it's working, bro - you'll start bleeding from the ears; the boost is frighteningly loud and the EQ circuit is very very efficient.

Other than the above, I cannot help but there are one or two bods here, and over at Matsumoku, too, who really know this stuff so keep asking the questions; someone is bound to help!!

Thanks for the quick reply.

I reckon that I have sussed the problem. On inspection into the gubbins full of wires, I notice one that is not connected at the Jack Socket. I have checked the wiring diagram on Westone Info and it looks like someone may have changed the Jack Socket at some point. The loose wire is the negative from the batteries and should be connected to a third terminal on the Jack Socket for switching the battery out of circuit when there is no Jack Plug in. The Jack Socket on this one only has two connections like a regular guitar Jack Socket. Not right me thinks.

Martin.

Sounds like you've found the problem Martin. That's always the the biggest part of fixing up these old gals, eh? Lord have mercy there are so-o-o-o many wires in there! Very scary place. You did well to trouble shoot her.

Having said that I don't know off hand, of a source for a proper jack but I'm reasonably sure (he said, fingers crossed) that you should be able to find one.
Let me know if you need pictures of the original jack and I'll pop the hood on mine for a shoot.

I wonder if this might be why the active circuit on my Phoenix is dead...

YAY!! A win... good catch, bro!! I'm quite sure a 3 pin socket is dead easy to source - famous last words!! - and once plumbed in, good to go!!

Warren, which Phoenix had a boost circuit?? I didn't realise that they did it as well; the Electra site makes no mention of it, but I suppose it makes sense, eh!!

I have had a root through my bits and bobs but I haven't come up with a suitable switching socket yet. I have the odd dud FX pedal that I may be able to nick off as they are usually the same type. Failing that I am pretty sure that I will find one from a supplier. The guitar itself has come along pretty well from when I first got it. There were really deep pits in the fretboard for the first 8 fret spaces, which I have filled, levelled and stained. I have levelled and dressed the frets, shimmed the neck, changed the bridge unit, set the action, adjusted the truss rod, set the intonation and generally cleaned it up. All that's left now is this pre-amp to get working. I have to say that I am really impressed with its construction, except for the neck set angle. I had to put a fair size shim in the neck joint to gain the correct angle to enable the optimum string height. If I could lay one desire on it, it would have to be a locking trem system. It's down to personal preference of course, but I have a Kahler Flyer locking trem system on my Gordon Smith Custom that I gig with and I used that for the last 20 years. I just love locking trem units that you can do big dips and rises with, although before I had the Gordon Smith Custom I played with a guitar for 15 years that didn't have a trem, I used to bend the neck back and forth on it to get the effect. This Thunder neck is way too solidly built for that, but if I keep it I may just get around to installing one.

Well, Westone do have a single locking trem set up with the Bendmaster FT and Deluxe which are both very nice set-ups when ,well, set-up properly!! Some of the Panteras have them as do the pointies and some of the Spectrum models and the Genesis; they are Tom's design and really are beautifully made and work very well.

Tom has told me there was a prototype double locking Bendmaster that slipped through as well, and to keep a watch out for it; to quote the eBay wallies, it is "RARE"!!!

John, my 1980 Phoenix X640 bass has an active circuit. The previous owner didn't seem to understand that it wasn't functional and labeled the active on/off switch as a kill switch and the center detented tone knob as non-functional... and sent it my way with fresh batteries. Apparently despite having owned it for 20 years he'd never had anyone look at the electrics. I haven't gotten around to bringing it in somewhere, as I typically don't use active circuits and the passive tone is gorgeous. I'd have my computer techie friend look at the wires but I don't think I've seen a wiring diagram for the X640.

Like this one...

http://www.rivercityamps.com/electra/x640.php

... that is a sweetie!! Best you get it working, eh!!

Not quite John, that's the later, more Spectrum-like X640. Mine is the older version, when they had pickguards. Click here. I'll get it worked on soon as I can manage.

Hi John,

When you said that the batteries are so hungry that they can flatten in the length of a gig with the lead left in. Do they still flatten if you knock the pre-amp switch to the off position?

Oh, I forgot to say that I have changed the socket and its now working fine. I have to say that I am very impressed with the active tone. There have been a couple of small design/build issues that I have rectified but the outcome is incredible! I have never come across a guitar that comes close to rivalling my Gordon Smith Custom (which outstrips Les Pauls etc) until this Thunder. All I can say is Brilliant!

Martin.

That's it, buddy - you're hooked, eh!! Good to hear about the win; excellent stuff! Ah, yeah; I had my VA900 flatten a new set of 9Vs over the course of a 4½ hour gig when I left the lead in the guitar; normally that wouldn't bother me because I use the Roland PSM1 to power my pedals but that time I only had a delay and overdrive with me and not my pedalboards.

So, yes, regardless of what possie the switch is in, the lead being left in severely degrades battery life!!

On the subject of the two 9v batteries.... You mentioned that one of yours only powered an LED. When I put the meter on the battery hook up, I find that these two are in series which is giving 18v. Are you sure that there is only one of yours that has its only function of running the LED or do you think that it is possible that this is a little excessive for the addition of another battery and that you may have a tapping off one of the cells?

No; I'm just regurgitating what another Va900 owner told me about the set up a while ago... and bear in mind that Matt had active versions of most models so what I've got may not be the same as you have!! However, I'm more than willing to be persuaded otherwise as I've always thought that 1 9V battery to run an LED was excessive, even in the 80s!!

Would you take a pic or two of the cavity so I can have a look see if anything is familiar in there; the VA900 is a veritable rats nest of wires and circuit boards!!