Ask the Expert – guitar extension cabinets

David Norris emails:

“Loving the discussion on Valve Amps. Having recently upgraded from a 60 Watt solid state amp to a 15 Watt Fender Blues Junior, the improvement in tone is amazing – people ask me what effects I have on when often its just the amp! It is definitely loud enough for practice, and for services (with PA) for several hundred people.

The only problem is that now I have got used to the amp I want it to sound better as it can sound a little ‘boxy’. I am thinking of getting an external speaker for it that I could then use with a head when I can afford a serious upgrade. So what do you recommend?

I have thought about a 1 x 12” but would this bring a real improvement in tone? Is a 2 x 12” better in the long run (and can any of them be used vertically to get the sound off the floor)? I know there are a lot of Marshall cabs on ebay but half of what I play is clean and I worry the Marshall would sound muddy?”

Andy replies:

Yup, the ‘boxiness’ can sometimes be to do with the speaker itself or the dimensions in the cabinet, design of the cabinet or a combination of the above.

So if you are thinking of getting a head at some point then the right cab could be a worthwhile investment for now but its not really a simple ‘buy this, it’s the best’ answer, there’s lots of variables to consider. Thing is the ‘right’ cab to match to your current amp could be a bit of a trial and error scenario so if you can, do hook it up through as many as you can to hear the differences. I wouldn’t rule out a 1×12 just because it’s similar to the 1×12 format of the Blues Junior. Of course as a general (very broad) rule 2×12’s and 4×12’s sound bigger than a 1×12 but the overall quality of tone is also impacted hugely but the choice of speaker, the design of the cab, the woods used etc etc etc.

So for the speakers check out its Db rating as that has a large implication on overall volume levels, the magnet construction materials. I prefer an alnico speaker as opposed to a ceramic one for sweet clean tones and really like the old Celestion Blue, but its expensive….Most of the main speaker companies have back to back audio comparison clips on their websites or Youtube so check out Celestion, Jensen, Eminence, Weber etc. Also try a few open and closed back cabs to and hear the differences for yourself and see what you like. For woods, MDF is cheap and heavy, plywood is sturdy and used in a lot of rock/Marshall cabs, pine is light and can sound really great for clean woody tones but is a bit more expensive. Plus the overall internal size of the cab makes a difference too. Of course the more you pay will give you better quality speakers, woods and construction so a cheapo 2×12 with budget speakers might not be much better/that what you’ve got. The Marshall 2×12’s you mentioned wouldn’t necessarily sound muddy as such, it just depends on the speakers used – a lot of stock ones come with Celestion GT12 75’s which are reasonably bright.

Also consider the weight issue too. My 320watt Marshall 4×12 sounds big and chunky but weighs a ton so it never goes anywhere. I simply can’t be bothered and unless you are playing big rock gigs its arguably it not worth the effort. That said I know plenty of players who love their 4x12s and think nothing of lugging one around in the back of their car. Maybe I’m just lazy?!

Another option would be to do an internal speaker upgrade in the Blues Junior itself. The stock Eminence is a fairly budget unit replacing it with a higher specced model from one of the above companies could do the trick. Just make sure the ohm rating is the same.

So do a bit of homework. Google Fender Blues Junior upgrades and see what you get. Alternatively if you can’t try beforehand and buying off Ebay a used Marshall 2×12 will probably sell for what paid for so it might be worth a punt if you like.