Acoustic Foam

[GrahamRB]

In the chanter/bag design thread Mike Nelson mentions 'Acoustic ' foam... in my Ross split stock there's a piece of foam that looks quite 'open'. A google search brought up loads of 'Acoustic' foam ... for sound proofing!! Wrong stuff I presume as it looks very 'closed cell'.

Where might I get some of the correct foam, sufficient to do 4 or 5 split stocks, please?

[pipemakermike]

Hi Graham

Any reasonable open cell foam will work. I started with a lump of foam that was part of an acoustic test rig at work but I have since used any sort of soft foam that I can find. The foam should be sufficiently open that you can easily suck or blow through a thickness of it and it should be soft i.e. if you squash it flat it should just bounce back to its original thickness.

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[GrahamRB]

Thanks Mike ...I'll have a dig around for something suitable.

[Julia Say]

Just be careful it isn't so thick that it touches the top of the the reed, or is very close to so doing. I removed mine: I found no need for it. Eventually it got clogged up and I suspected it was restricting air flow rather than helping.

Julia

[Francis Wood]

The presence of acoustic foam is a good solution for the adverse effects of neck resonance, but only if that resonance is a problem and causing inconsistent tuning difficulties.

Neck resonance in itself is not a problem and indeed is very much part of the sound of the instrument, together with the vibrations emanating from the bag. If you touch the bag, you will feel it vibrating; it is therefore radiating sound. This aspect of the sound is very noticeable when the listener is standing beside or behind the player, a sound lacking in the upper harmonics enriching the sound emanating directly from the tone-holes in front.

Whether you like that aspect of the sound or not is another matter. But its existence is often unrecognised.

Perhaps the overall sound is also affected by the presence or absence of a fabric cover. Now there's another thread!

Francis

[Barry Say]

The presence of acoustic foam is a good solution for the adverse effects of neck resonance, but only if that resonance is a problem and causing inconsistent tuning difficulties.

If I may paraphrase Francis here, "The plug of foam will alleviate a problem which is occurring elsewhere". To me this means that it is a workaround, it doesn't solve the problem but it lets you get on with playing. That is a good thing as far as I am concerned, especially when my cure for the problem would be a new bag and you can think of £50 as a minimum price for a Jackie Boyce bag + dressing and fitting.

Colin Ross' adoption of the foam plug was either during the time I was attending his pipemaking classes at Killingworth or shortly thereafter. As with many of Colin's innovations it came about from dealing with problems his customers brought to him. My recollection was that Pauline Cato was a student at Sheffield University, and along with her studies in languages (ahem!) she spent some time playing in a ceildh band ( Rodger the Badger) and various music sessions. She found that she was having problems with here chanter reeds, and it seemed that it was due to the atmosphere in smoky bar-rooms and other such dives which NSP players were formerly accustomed to frequent . AFAIK Colin devised the foam plug as a dirt filter. It also works well for catching the little black pebbles (bogies?) which come out of undressed bags with the suede inside. I don't think that Colin ever saw this as a way of resolving neck resonance which he always cured by keeping the chanter stock short, changing the bag, or finding a reed which would get around the problem.

More on this elsewhere

Barry

[Julia Say]

Colin was recommending foam plugs before the 1990s, but yes, primarily as a smoke filter (happily now not needed). An early-ish Ross chanter came back for servicing a while back, and the foam was beginning to crumble, as it all does after a number of years.

Julia

[andymay]

Hi

I generally find a neatly-cut section of a washing up scourer does a good job in this context.

I'm also a fan of glueing a similar (but larger) disc of sponge into the back of the dronestock. I first did this to avoid drone reeds falling into the bag, but observed that the drone sound and stability afterwards was 'different' , suggesting that 'some effect' had taken place. Not to be too specific there but i have found it to be helpful.

Recently while reeding up Henry Clough's Reid pipes i found that a few minutes with the washing-up sponge and the kitchen scissors improved the sound and stability of the drones no end......

A