Count Bassie

She Kinks

Raul Butterfield

Nickie Fixx

Fete Way

31 minutes ago, Baloney Balderdash said:

Just got the ESP/LTD B4JR bass in the door that I bought used Friday yesterday.

It's a just 28.5" scale length short scale, with a Basswood body, and a Maple neck with Rosewood fretboard.

And after a thorough setup, and having the stock pickups, which honestly sounded decent enough, for an EMG Geezer P pickup, it sounds non less than amazing.

Really nice tone, both finger plucked and using a pick, and the sustain is pretty substantial too.

Even the low E sounds great, despite the short scale length.

It's also very light, the body being made of Basswood, which does make it prone to neck dive, but nothing a wide grapy strap can't solve.

Now the bad things, when I got it it had one of the most horrible setups I ever saw, and with loose input jack socket, that was easily fixed though, however the nut slots are cut way too high, and it got some pretty sharp fret ends, that you can literally cut your hand on if you are not careful, and will probably have fixed that too at some point by a proper luthier.

The thin U shaped neck will also take some getting used to, it is not exactly beefy, but it kind of feels that way, because the neck profile is so round.

The frets are not perfectly leveled leveled, but still well enough that I can get it to my preferred string action (about 2mm (~5/64") low E string at 12th fret) without any issues or string buzz whatsoever.

Truss rod works as it is supposed to, and neck seems stable.

Tuners are not the best, but they work just fine.

Here it is (excuse me for my old crappy digital camera):

 

I got it for what equals about 30£, a deal I could simply not pass.

 

That's a little booger! Cool that it's nicely proportioned though. Get those fret sprouts filed though... Not cool to bleed all over the carpet! 😁

I think this game could be more fun if another rule were added.

Ruth

Kush

6 minutes ago, SimonK said:

 

Yes - sorry I don't have anything prior to Mk V but I thought there could be some similarities.

You know there might be more than I've been led to believe, but it's possible this amp had been serviced with non-spec'd or alternate parts- which might have to do with why the output is so anemic. I'm not the tech though, and life's too short for some things...

Also, as far as I've been able to find, there seems to be no Mk IV schematic in existence. ? Trace Elliot has a rabbit hole of hardly documented work.

Thanks again for the files though!

15 minutes ago, prowla said:

I don't think it was an AH150, as that had quite a shallow depth.

Ah - the pics show it has a UV tube too, so that rules it out anyway.

Yes, this one's a 250.

1 hour ago, SimonK said:

Trace-Elliot GP11 schematics+parts list.pdf 930.45 kB · 1 download

Yep, this set goes back to the Mk V, and there are some significant differences between it and the Mk IV.

Thank you for sending those though! I've downloaded them and I'll bet there will be another old tank added to the pile within the year, 😁. 👍

3 hours ago, Matt P said:

I've just had my mk4 serviced by Martin @Stoneham they might have some useful information? 

 

Matt

I'm all about it, I'll look them up. Thanks again Matt!

(Sent him a mssg... Ashdown, Peavey and BAS next...)

3 hours ago, Stub Mandrel said:

 

The GP11 mk iv won't be very different from the mk 5.

Apparently there are some meaningful differences. The MK IV diverged from the MK V in the preamp I think, that's the report. He's been, as I say, reverse-engineering his way through some of it. 

I'm hoping to eventually get to someone who was part of the design team from that period.

Alright then...

My tech has the amp opened up again, as the volume doesn't seem to be what it should. 

Apparently the signal travels from several points between the power section and the preamp, and the preamp is quite complicated. 

At this point the gain on the preamp has to be all the way up to get even moderately significant volume. The model I have, the MK IV, doesn't have a schematic or any kind of plan available, so I'm starting to dig in and see if I can talk to any of the people who had a hand in the early designs. 

So far my tech has been essentially reverse-engineering his way through the amp, and it's exhaustive. 

I'd be very interested in hearing about any sources of first-hand info about the MK IV'S design. 

Thanks! 

It's off to Ashdown...

Ready to receive... Went with gloss black, Rust-Oleum clear lacquer and #0000 steel wool. 

So it's been cleaned up, which took a lot more work than anticipated. The fan was caked with some kind of mud or sludge, and the preamp module was taken apart and gone through methodically. I almost didn't want to know what went on in the life of the guy who owned it previously...

Anyway it's working, but it's not putting out nearly the power it ought to be. The tech has it back again, and is going through the op amps that get signal from the power supply. 

It's got a surprisingly small power amp I'm told, due to the structure of this thing. It seems the 250 through 500 models used the same transformer and big blue caps, but the number of power transistors was the difference in the final product. 

But, it sounds like I expected it to, which is great... Hopefully the output comes up to spec, and I'll install it into the sleeve. 

Pix to prove it happened!

(Typos fixed!)

20 hours ago, Jean-Luc Pickguard said:

 

Simply Ned

Simply Redo

Depeche Mole

Modness 

The Cart

The Sax Pistols

3 hours ago, BassmanPaul said:

Don't worry Bro - we'll help you find it again!!

 

Oh boy! Popcorn time! 😃

4 hours ago, Sparky Mark said:

That I get! 😂

I'll give that info a little time tonight, thanks you guys, I appreciate the interest and help! 

The math before me is like an irritating repellant before a garden-pillaging rodent. 😂

Ok, fair enough, I stand corrected.

1 hour ago, agedhorse said:

Not necessarily. I'm still measuring the same way today as I did in the 1970's and every product I have designed uses power based on RMS metrics and states THD...

The guy who's been repairing my amps the last 6 or so years there me that measuring at 1KHz takes less power than lower frequencies, so the rated power brings a higher number. This is incorrect? 

On 12/06/2025 at 15:49, markorbit said:

I toured a MkIV AH250 through a red stripe 4x10 back in the day. Wonderful amp although 20 years later I acquired the same model for nostalgic reasons and the sound wasn't how I remembered it.

I got into the SMX 12 band stuff with the tube and the dual-band compressor. That was my favourite preamp and I'm not sure if anybody has bettered it.

Power ratings are so unpredictable. I hear people complaining today that a relatively recent 300w Class D head is hitting it's limits. 300w seemed a lot in the 80s.

Power is measured differently than it used to be. The numbers get blown up and it seems like power just ain't what it used to be. It is, it's just sold "differently"... Advertising...

On 24/01/2021 at 16:50, Deedee said:

Here's the one covering the SMX. It also shows the GP7 (still Series 6 at this time) and some of the Valve series.

There's another brochure that came after this that covers the SM range along with the SMX range.  I'll sort that one tomorrow. 😉

 

 

I remember drooling over the SMX line in '95... 

On 24/01/2021 at 16:19, thodrik said:

I never knew that Trace did a 2x18 cabinet.   Fantastic. Impractical but fantastic.

Old school dub reggae players could get with that I think.

Thanks everyone for posting. 😎👍

10 minutes ago, Sparky Mark said:

A rehearsal studio in Hertford used to have a Series 6 410 and a Series 6 112 combos  that sounded amazing. I think they were both rated as 150 watts without an extension cab. They were what brought me back to TE amps. I'm not one for mid cut pre shapes, but there's something about that original Trace Elliot pre shape button that just works so well.

I like the presentation and then bringing in some mids with the graphic.