Converting a Roland Cube 60 combo to a head

[sigutis]

Hello everyone. I just found this forum and this is my first post. 

I have this idea of converting a Roland combo into a head.

I have an offer to get a decent diy 2x12 cabinet with a single Eminence Legend 1218 speaker in it. I want to use the speaker from my Cube to complete the 16 Ohm cabinet and also refactor the Cube into a more head shape.

Currently the Cube allows for 8 Ohm external cab. I haven't yet opened the Roland up yet and don't know how the speaker extension is implemented.
I would guess that the inner speaker wired in series with the external jack? Would it be stupid to assume that with the inner speaker moved to a cab everything would even out?

[Roly]

Hi sigutis, welcome.


http://www.ozvalveamps.org/repairs/cube40.htm

If you can find and post a circuit of the Cube-40 or 60, it may be redeemable.

[sigutis]

http://www.freeinfosociety.com/electronics/schematics/audio/pictures/rolandcube60.gif

[J M Fahey]

Is that one yours?

Because there's at least 3 very different Roland Cubes out there.

The schematics posted above relate to the 80's (typically orange)  ones.
Quite close to JC120 of that era, without the Chorus, of course.

In the early 2000s they made the Blues Cubes.
Still discrete and very tubey sounding.

In the 2010s they came out with the multi effect multi amp simulation digital ones.

never found a schmatic and anyway suspect they have a square, 100 pin per side SMT microprocessor which does everything and probably a Class D power amp.
And maybe a Switching Supply.

Which on is yours?

Care to post some pictures?

Rehousing it in a head is not difficult.

I would not even cut the original cabinet, because it's messy, you still have to work a lot to close it, round the new MDF, fully recover it (you destroy the Tolex), etc. so actually find faster and easier to make a new cabinet housing just the electronics and keep the original combo cabinet for later reuse or to sell it easier.

If it has an 8 ohms extension speaker, it will drive your other speaker.
Usual extension jack is wired in parallel withn the main speaker ... a few amps put them in series, so follow the wiring to check or simply plug an open plug (with nothing attached to it)  in the extension jack: if sound cuts off, they are in series; if not they are in parallel.

[sigutis]

Is that one yours?

Because there's at least 3 very different Roland Cubes out there.

The schematics posted above relate to the 80's (typically orange)  ones.
Quite close to JC120 of that era, without the Chorus, of course.

In the early 2000s they made the Blues Cubes.
Still discrete and very tubey sounding.

In the 2010s they came out with the multi effect multi amp simulation digital ones.

never found a schmatic and anyway suspect they have a square, 100 pin per side SMT microprocessor which does everything and probably a Class D power amp.
And maybe a Switching Supply.

Which on is yours?

Care to post some pictures?

Rehousing it in a head is not difficult.

I would not even cut the original cabinet, because it's messy, you still have to work a lot to close it, round the new MDF, fully recover it (you destroy the Tolex), etc. so actually find faster and easier to make a new cabinet housing just the electronics and keep the original combo cabinet for later reuse or to sell it easier.

If it has an 8 ohms extension speaker, it will drive your other speaker.
Usual extension jack is wired in parallel withn the main speaker ... a few amps put them in series, so follow the wiring to check or simply plug an open plug (with nothing attached to it)  in the extension jack: if sound cuts off, they are in series; if not they are in parallel.

You are right. I haven't given enough attention to different iterations of the cube. Mine is of newer kind, with amp mods and digital fx.

I do think it's a great amp. I like it better than Fender, Marshall and Laney tube/ss amps I've used. Even got rid of a Fender Champ with a tube rectifier I've made (and had sentiments to) when I got my hands on the Cube.

Great idea with the open plug. I am going to try it tomorrow.