TE AH400smx

[stevemaiden]

[attachment=178844:TE switch.jpg]Hi, I'd appreciate any help pointing me at a UK supplier for this switch unit used in my recently acquired (yesterday) AH400smx.
Model #: 73-SWT-F2UEE



I found that the pre-shape & the graphic eq switches didn't click in - upon examination of the switches I discovered the tiny U shaped metal "prongs" - see arrow in pic - were missing from the offending switches. As a quick solution I've pulled out the prongs from the DI earth switch & the passive active input switches & put them in the switches I want to work - I use passive bass & don't envisage using DI earth at any point in the near future. If I can source a couple of replacement switches I can simply swap out the prongs to save de-soldering & re-soldering new units & have a fully functioning set of switch units!

As a secondary question the input from both my passive basses (Fender Jazz V's) struggle to make the input gain light even the green LED - they are OK on my AH 250, so it seems to point to the preamp in the AH400. Does this point to a problem with the AH400 preamp??

Edited December 17, 2014 by stevemaiden

[Subthumper]

Hi, I might have something suitable in my workshop, probably off a scrapped marshall. How many do you need? If I have some I'll chuck em in the post. 're your question about the level LEDs, does the amp sound ok? It could simply be a question of the LED drive circuit being at fault. I've worked on a lot of traces of that age and its well worth going over the whole amp and looking for solder joints that are starting to fracture esp the ones on Jack sockets, pots and sliders.
Cheers Just

[stevemaiden]

Hi, there's 2 switches us due to lack of the metal prong thingy - the prong just clicks into a hole to keep the switch body in when pressed - clicks out when pressed again - cycling the switch on & off. I've visually checked the rest of the amp & blown off all the accumulated dust internally, which wasn't to bad. The amp seems to date from 1990/91 going by an inspection signature - it actually sounds great - I'm just concerned the input gain level being so low may point to a fault?

[Subthumper]

Ok I'll see what I have tomorrow.

Edited December 17, 2014 by Subthumper

[VTypeV4]

If it's the graphic and pre-shape in / out (with accompanying LED indicator) then it's 'momentary' switches that don't click like the active / passive or pre-shape 1 / 2 buttons so there may well be nothing wrong.. If the LED lights and you can hear a change in sound then it's working fine..

[Subthumper]

I have the exact ones, will PM you.

[stevemaiden]

Hi & thanks for the replies. Subthumper, I see after V4's comment that I have no need of the switches!! It seems in my haste to clean & "sort" the amp I have mis-diagnosed - the graphic & pre-shape are indeed "momentary" switches with LED's & do not require the metal prong thingy to function! After re-stripping the amp & swapping back the metal prong thingies & testing the amp - it works fine!!

The input level does seem low tho' - & this is with 2 passive basses & probably may be the LED's as the amp does sound great!

[VTypeV4]

Glad you got it sorted!

As for in the input level, I found it normal to run the gain between 5 and 7 to get the yellow lit although I had to run it even higher with my old RockBass Streamer. Remember it's also proportional to the boost / cut on the EQ too so if you have a lot 'chopped out' on the graphic then it will need to be turned up more. Double check the graphic level knob is turned up most of the way too as this will affect it also..

Good luck!

[stevemaiden]

Hi V4, the I'm running at 9 on input gain to get the amber light to flicker - even when when slapping! Finger playing barely gets the amber to light! - this is without graphic, just the pre-shape set to classic Trace (setting 1). The amp sounds good tho, a good purchase for £230.