Re: Where to get 4 off 12 inch speakers in the UK?

N Cook wrote:
J M Goodey <jgoodey@xxxxxxxxxxxx> wrote in message
news:3130303035313136459A45DA77@xxxxxxxxxxxxxxx
The message <endbs0$jmq$1@xxxxxxxxxxxxxxx>
from "N Cook" <diverse8@xxxxxxxxx> contains these words:

The owner managed to blow all 4 in a cab by overdriving them. 4x 12 inch
,
16 ohm, 60W , maybe replacements only up to 5KHz and add a tweeter or
two
I have a large useless cab cluttering up the place until he can find
something to replace. As they're obviously prepared to tolerate nasty
noises
while progressively failing they presumably don't need hi fidelity ,
just
cheap enough or I can see this cab going on a bonfire.
Yes, i've googled ,but 120 quid for 4 would seem to be the breakpoint
and
can find nothing like that.
--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/




Rapid Electronics of Colchester (of whom I have no commercial connection)
sell 12" 200w speakers for about £20:00 plus VAT. I have used several of
them in situations similar to yours.
www.rapidelectronics.co.uk

--
Jocelyn
jgoodey@xxxxxxxxxxxx
Tetigisti acu. (Titus Maccius Plautus 254 - 184BC)



I see a rock and a hard place coming up.
I would replace the 4 16 ohmers with 2 8 ohmer 100 watts and selector switch
bypassed, but for the same 4 bottle, 120W amp would that be the same oomph,
as they term it. ?
Although amp and cab are Crate make they obviously were not made as a
matched pair as amp has 16/8 ohm output setting and cab is 4 / 16 ohm
setting. I suspect they'd been running for some time as I received them ,
amp set at 16 ohm and cab set as 4 ohm , so they certainly won't be getting
the same oomph as amp at 16ohms and cab at 16 ohms.

Providing the speaker load matches the amplifier, you should get the same output, but the apparent volume depends on the sensitivity of the speakers - most of these so called 'high power speakers are notoriously insensitive. 'Classic' guitar speakers such as the Celestion G12H etc, were/are very sensitive and have corrugated cones designed to 'trash out' at high volume without destroying the speaker.

Is there a way of perhaps saving stressing output matching transformer in
the case of the speaker load going open circuit?
eg a high watt 50 ohm resistor in parallel with each speaker of the serised
8 ohm speakers so the load does not go totally o/c and some sound until
replaced , rather than zero sound . Extra permanent resistor load would be
un-noticeable I'd have thought.

Some of the Selmer amps had a high wattage resistor across the output jacks to help in absorbing some of the energy in the case
of a loudspeaker cable becoming unplugged. That`s probably the safest way to go.

Before you put too much money into this cabinet, do you realise that you can buy a Behringer 400 watt 4x12 for little over £200, or much less if you shop around?

Ron(UK)
.

Relevant Pages

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  • Re: I keep blowing damn speakers! Why?
    ... Peavey cabinet is 4 ohms for the horns and 4 ohms for the 15. ... As for the speakers being different I will argue that one, ... Ok, there is a difference, on is 4 ohm and the other is 8 ohm. ... have the specs for the Amp and the 15, ...
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