New to me - Polytone Mini/Teeny Brute

[garybaldy]

My Loar 700 has a new companion. It usually goes through a MBIII.
Found the teeny in a guitar shop in a small market town in England. Not a scratch or tear in the diamond vinyl nor any wear to the amp cover. I don't really know anything about the teeny but it's really neat! Sorry my pics always appear on their side.

[Hammertone]

My favourite Polytones. I've had one related to it since the 1980s. One replacement speaker and a couple of repairs later, it still sounds and works like a charm. I installed a switch to kill the speaker so I can run it with a variety of external cabs.

[Franz 1997]

Yes, my fave too. This looks like an early 80s baby or teeny-brute ( ie 8" or 10" speaker, nominal 80 watts output) in great cosmetic condition. Ivor Mairants guitar shop in London imported these for a time around '82, and they sold out quickly as there was nothing of similar quality available. The cost around £200 at that time.

It's worth pointing out that the capacitors in these amps were prone to failure because of the small cabinet and the consequent overheating in hard gig usuage. If the caps haven't been replaced, they should be. This is particularly importnat with these amps because, if the caps leak or explode, they can take out some other components which are now difficult to replace, though not impossible. One little secret is that there is a 7 amp fuse in a fuse holder on the power amp chassis itself - if you don't know about this and that fuse has blown, you might conclude that the amp is dead, when in fact the fuse has blown to protect against a short circuit.

You are lucky, this amp hasn't got the horrible "red-knob" circuit, which engages the worst distortion sound you have ever heard. No reverb either ( although these amps are notorious for broken reverb tanks if thet do have reverb - the tank was just screwed to the cabinet, and thus broke quickly).

Despite their temperamental nature, they sound wonderful and IMO as good as anything on the jazzamp market today. Well worth looking after and keeping going for another 20 years. But those caps really need changing after 40 years, if they haven't been. Ask me how I know...

[garybaldy]

Yes, my fave too. This looks like an early 80s baby or teeny-brute ( ie 8" or 10" speaker, nominal 80 watts output) in great cosmetic condition. Ivor Mairants guitar shop in London imported these for a time around '82, and they sold out quickly as there was nothing of similar quality available. The cost around £200 at that time.

It's worth pointing out that the capacitors in these amps were prone to failure because of the small cabinet and the consequent overheating in hard gig usuage. If the caps haven't been replaced, they should be. This is particularly importnat with these amps because, if the caps leak or explode, they can take out some other components which are now difficult to replace, though not impossible. One little secret is that there is a 7 amp fuse in a fuse holder on the power amp chassis itself - if you don't know about this and that fuse has blown, you might conclude that the amp is dead, when in fact the fuse has blown to protect against a short circuit.

You are lucky, this amp hasn't got the horrible "red-knob" circuit, which engages the worst distortion sound you have ever heard. No reverb either ( although these amps are notorious for broken reverb tanks if thet do have reverb - the tank was just screwed to the cabinet, and thus broke quickly).

Despite their temperamental nature, they sound wonderful and IMO as good as anything on the jazzamp market today. Well worth looking after and keeping going for another 20 years. But those caps really need changing after 40 years, if they haven't been. Ask me how I know...

Thanks Franz. Great info! My first impression is their doesn't seem to be quite as much treble on tap as I expected ie. compared to my MBIII. Caps? Cheers

[Franz 1997]

Thanks Franz. Great info! My first impression is their doesn't seem to be quite as much treble on tap as I expected ie. compared to my MBIII. Caps? Cheers

I don't think old/bad caps would affect treble response; all-original Poly amps don't really have a lot of treble unless the 3-way switch is in the "brite' position. All MB amps have the same basic circuit, so it's really the cabinet size and the speaker which affect the final sound. But it would be a clever move to gently take off the back panel, with the amp completely disconnected from the mains and, without touching anything, see if the two large upright capacitors on the lower chassis, next to the upright black heat sinks, are grey in colour, about 5" tall , and are not held in place with clamps. If so, get the amp serviced asap, and those caps replaced. It would be best only to use the amp for short periods eg 30 min, until the caps are replaced, to avoid heat build-up in the small cabinet.

Edit: I know this sounds super-cautious; my experience was that about 10 years ago those same 30-year-old caps in my baby-brute exploded after I left the amp on by mistake for a few hours, taking out some other components, including the original speaker. Once bitten...

Another thing you could try is squirting a bit of switch cleaner into the 3-way slide switch on the top panel.

[garybaldy]

I don't think old/bad caps would affect treble response; all-original Poly amps don't really have a lot of treble unless the 3-way switch is in the "brite' position. All MB amps have the same basic circuit, so it's really the cabinet size and the speaker which affect the final sound. But it would be a clever move to gently take off the back panel, with the amp completely disconnected from the mains and, without touching anything, see if the two large upright capacitors on the lower chassis, next to the upright black heat sinks, are grey in colour, about 5" tall , and are not held in place with clamps. If so, get the amp serviced asap, and those caps replaced. It would be best only to use the amp for short periods eg 30 min, until the caps are replaced, to avoid heat build-up in the small cabinet.

Another thing you could try is squirting a bit of switch cleaner into the 3-way slide switch on the top panel.

Thanks again Franz. I'll do that later today.

[Hammertone]

Mine has the red knob and I find it hilarious. No shortage of red knob love here. Last service was a year ago, to replace the bridge rectifier. Mine has an old 8-ohm Celestion 8" replacement speaker, installed 20 years ago, when the amp blew up. I have been cranking the amp since then without issue, other than the most recent failure. "Service every twenty years, whether it needs it or not" is my Polytone motto. Similar to my motto for my many vintage Hofner archtop guitars: "neck reset every 50 years, whether it needs it or not."

Mine also has reverb, which stopped working years ago. I never bothered fixing it because I have various reverb-in-a-box devices, if I want reverb. A couple of years ago the reverb started working again on its own - the ghost of Tommy Gumina has taken residence, at least for now.

Whenever it finally croaks, I will use it as a doorstopper. Great little amp!

Also, you need to fix the foam grill cover. Here's the right way to install it:

[garybaldy]

The back's coming off this evening. Perhaps I should have done it before I bought it!

[Greentone]

Yep. That's a Teeny Brute from the best era for Polytones. I think the Teeny (10") and the Baby (8") Brutes are the absolute best of the bunch for archtop guitars. They will really turn heads with a Gibson ES-175.

Enjoy your amp!

[garybaldy]

Yep. That's a Teeny Brute from the best era for Polytones. I think the Teeny (10") and the Baby (8") Brutes are the absolute best of the bunch for archtop guitars. They will really turn heads with a Gibson ES-175.

Enjoy your amp!

Thanks GT
My 175 hasn't had a look in yet.
And I've yet to take off the back panel!

[pingu]

be carefull with those big
electrolytic caps ....

they can bite bite you even when the power is off .... !

[Doctor Jeff]

Nice guitar and amp!

Hint: when posting pictures from an iPhone or iPad edit the picture first and save it. This will save the orientation information, otherwise the picture will be oriented whichever way the top of the phone was pointing.

[garybaldy]

Nice guitar and amp!

Hint: when posting pictures from an iPhone or iPad edit the picture first and save it. This will save the orientation information, otherwise the picture will be oriented whichever way the top of the phone was pointing.

Thanks DrJ
I'm pretty sure the top of the phone was pointing up when I took the pics and they show on my phone the right way up.