Re: [Harp-L] H Dustcap

[David Brown <nonidesign@xxxxxxxxx>]

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.




On Thu, Nov 17, 2011 at 10:49 AM, Dan Hazen <bluesmandan76@xxxxxxxxx> wrote:

> >From what I understand, and based on my correspondence with Weber reps,
> the
> H dustcap is simply a larger dustcap (not as big as those on bass speakers,
> but larger than typical guitar speakers) designed to reduce treble
> frequencies, thus reducing feedback.
>
> For comparison:
>
> My Sonny Jr has speakers with large dustcaps.
>
> I did a little experiment a few minutes ago... I took my Marshall Class 5,
> which is far too trebly to use for harmonica, and I plugged it into my 4x10
> bass cabinet. It did reduce feedback.
>
> My Harpgear 2 does not have a large dustcap, but it has a funny looking
> raised dustcap (like a button or a thick poker chip) and it appears to be
> doped all around the dustcap, I would guess to give the same
> treble-reducing effect. I plugged the Harpgear into the bass cab, too, and
> it didn't really help it much... but I can play the HG2 very loud without
> feedback... it did however thicken up the sound of the Harpgear, and give a
> whompier bottom end. (Is 'whompier' even a word?)
>
> And then there's my Peavey Pignose. I took the guts of a Pignose Hog 20 and
> stuck them in a Peavey combo (40 watt Express 112, I think), b/c the
> Peavey's power section had gone bad, and I hated the Pignose speaker.
> Worked really well. The Peavey speaker happens to have a huge dustcap,
> almost 4 inches.
>
> I would think that you could tame a particularly feedback prone amp by
> plugging it into a bass cabinet. The trick would be matching the wattage of
> the bass cab with that of the amp... bass cabs are usually rated very high,
> whereas harp amps are usually fairly low watt amps, and if the amp is too
> low for the speakers, then articulation and sensitivity will suffer... You
> probably don't want to plug a 5 watt amp into a 400 watt cabinet. HOWEVER,
> that inefficiency MIGHT be an added help against feedback.... I think. I
> don't have a billion cabs lying around where I could try every combination,
> but I think that's the way it would go.
>
> I'm actually surprised that more guys aren't doing this sort of thing,
> using harp/guitar heads with bass cabinets, as it really does give a great
> thick bottom end to your sound... and after all, the working standard for
> harp amps is the Bassman, which was, obviously, originally designed as a
> bass amplifier.
>