[Harp-L] Re: H Dustcap

[Dan Hazen <bluesmandan76@xxxxxxxxx>]

Yeah, I'm aware of all that. But I think you might have missed the simpler
point of the post. Harp players tend to want thick bottom end and less
feedback. The right speaker can accentuate the lower frequencies and help
reduce feedback. If someone has a feedback prone amp, they can try plugging
it into a bass cab, and might get decent results.

By "match the wattage"  I of course meant "match the wattage correctly" -
which is typically double or thereabouts, as in mating a 50 watt amp to a
80 or 100 watt speaker rating. You don't want to blow your speakers. And
you obviously have to match the ohms, as you don't want to blow a
transformer.

As you are doing the sort of thing I was suggesting, using bass speakers,
I'd think my logic was headed in the right direction. What kind of cabinet
is your 4x8 setup? Big, small, closed back, open back, combo, ported, etc?
What is the 1/3W amp you are using?

I've played some old Mascos and Bogens that were particularly "wiry" and
would feedback in an instant. I'd love to plug them into a bass cabinet and
see, er, hear, what happens.




[I think you also have to check the ohm rating of the speakers you have in
the cab to match it to the particular output of the amp.]

[Dan,

You are adding 2+2 and getting 5 somewhat.

Dustcaps are just one component/factor, you are overlooking SPL
(efficiency),
resonant frequency, frequency curves, live listening tests etc.

I play a 1/3W amp through a 4x8" cab loaded with bass speakers out of a
Traynor
cab...the wattage handling of the speakers is many, many magnitudes more
than
that the amp can produce (the amp produces hundredths of the W the speakers
will
handle)....there is no loss of articulation. You never match amp wattage to
speaker wattage, because tube amps are rated at clean output and are often
played beyond their clean W rating, speakers therefore are typically rated
for a
minimum of twice the tube amp wattage (often you will see speakers with a
"tube
& "SS" rating the SS rating being more than the tube rating for this
reason). In
the 50's they used low wattage speakers...because that's pretty well all
they
had available at a reasonable price, some amps were strangled by tiny output
transformers so that they couldn't make a lot of bass, allowing the use of
low
rated speakers that would outlast the warranty period.

The 4x10" Fender Bassman did not use bass specific speakers.

Bass specific & PA speakers can work very well in some amp cabs used for
harp,
other times when overused, they can make the tone flat & overly dark (a
guitar
speaker may be designed to reproduce from 80Hz upwards to 6KHz or 7KHz, bass
speakers more often cover the range of 50Hz to 3KHz-4KHz, this has a
pronounced
effect on high end/detail). It is better to think in terms of specific
speaker
models rather than focus on largely arbitrary features like dustcaps &
"bass/guitar" designations. In a multispeaker array it is obviously
possible &
often desirable to mix speaker type for a more complex tone.

The size of the dust cap will also be relative to the size of the voice
coil, a
speaker with a 2" voice coil will obviously have a bigger dustcap than a
speaker
with a 1" voice coil. More efficient speakers use larger voice coils & have
bigger dustcaps than less efficient speakers, irrespective of intended use.

Very efficient speakers with very large voice coils & magnets can be
overkill,
increasing feedback. Conversely, particularly innefficient speakers (for a
given
size & voice coil) offer no advantage in reducing feedback & will reduce the
volume, kill the tone of your amp.

Speakers are always chosen by builders & designers principly for their
tone...it
doesn't matter what the manufacturer designed it for, if it sounds good,
use it.]