Adding speaker cab functionality to a combo

[kiat]

I've in old Traynor Bloc80b that has miraculously been with me since new, despite 20+ home moves and life's ups and downs. For the past 7+ years it had been making very loud snap, crackle and pop noises, always when turning off and sometimes when any of the pots sere moved. It was unpleasant for everyone. I couldn't risk it at a gig.

 

So I decided to see if I could reuse it as 15" speaker cab but without losing any existing functionality. A few howtos showed just removing the internal speaker cable from the amp and routing it to an external amp via a jack, but it solved only part of the problem. 

 

The solution is very straightforward, I did it in a couple of hours, because I had to find all the right tools, etc but realistically it's a half-hour job.

[kiat]

The solution basically involves adding a special kind of jack socket to the combo, which switches the amp from onboard to external simply by inserting an external speaker cable.

 

Parts:

* Switched Jack Socket (Neutrik NYS215 Stereo 6.3mm PCB)

* Speaker Cable (Red & Black 2.6 x 5.2mm 6Amps)

* Soldering kit

* Tools

 

Red wire to the socket terminal the jack tip (positive). Black to the barrel (negative). Make sure you have the default terminals connected to the onboard amp. 

 

Actions: 

0. Remove the combo from power

1. Cut cable from internal amp to speaker 

2. Extend speaker cable with new

3. Drill hole for back 

4. Install the new switching jack

5. Solder the existing amp cable to the jack 

6. Check that works with power on and a bass connected to the existing combo input jack.

7. Power off

8. Solder the now extended speaker cables to the other side of the switching

9. Repeat the check with your bass to external amp connected via speaker cable to the new switching jack socket.

10. If this works, you're done, so replace everything and add some kind of sign what this new jack does.

 

Tips:

* take pictures so you can recall the existing layout and to make posts like this!

* cut the wires close to the speaker, so that you have enough internal amp cable to route to the interval amp.

* be careful with the soldering iron and don't touch any other wires with it that you don't intend to. 

" I had a connection block, but a Wago or splicing the speaker cables

 

 

[kiat]

And fixed the peeling Tolex while I was it with this German cobbler glue - the glued parts have to be hammered for maximal adhesion! Thought it might work on this solid state combo and it has. Would have needed to find something else if it was a valve amp!