sorry, me being a GHBer know no of the great complex design of the almighty UP and parden you to ask what is that round white cylinder type thing off of the bass(?) drone for?, and should it be split in two halfs (looking at an UP of my m8s)
its “3A” by the way thats not my m8s UP just one i found on the net
It’s known as the bass drone resonator… gives the bass drone that “hummm” or “buzzz” sound.
Can also be called a bagel, if you’re feeling particularly hungry.
“Split it in half”, you ask? Why would you want to do that? You’d ruin it.
For the cream cheese of course 
It’s basically just there to redirect the sound so it isn’t blowing sound up on the player.
Patrick.
I think he is using the word ‘split’ as an adjective describing the situation as it stands at this present moment in time, not as a verb describing what he intends to do with said resonator.
If it is the former, then it is most likely broken in some way.
If you mean the latter - don’t!
Cheers,
DavidG
… yeah, and don’t play Hockey with it either. 
Hockey? Mmmmmm … hockey … I remember hockey … 
djm
I used to play bar league hockey in Duluth Minnesota many, many years ago. When I stopped playing, I lost all interest in the sport. I can’t say I miss it much, but I feel for the ones who do. 
Ah, yes, those were the days… I remember playing hookey… 
I’m not so sure that the trumpet resonator on the Bass serves any real purpose.I have a straight drone with no resonator(same as the little and middle drones)I have also heard pipes played without any fitting on the end and the Bass sounded fine I have also seen plenty of examples on this forums pictures o pipes with resonators turned back straight toward the player!!so what exactly does it do?other than aesthetics I think it has little if any real impact on the end sound…I also think that the tuning pin on the regulators is something that shouldnae really be there but has become accepted over the years…if ye look at some of the earlier sets they did not have tuning pins on the regs coz ye didn’t need one if the thing was made in tune in the first place(it would be a closed chanter and ye don’t have tuning pins on chanters)so these earlier makers got it right and I know of one maker today who doesna need tuning pins for his regs..At some point in the evolution of them I think someone decided to put a tuning pin in to correct a problematic regulator and the idea caught on.A bit like some makers today who stick a rush up the chanter bore as norm which would indicate a basic design fault…rather than find out why the thing needs to be rushed or whatever in the first place.I have a set of regulators by Andreas Rogge in C and I have never had to adjust the tuning pin,in fact I am confident I could remove the tuning pin altogether.The only slight alterations if needed are easily done via the reed!!
Slán Go Foill
Uilliam
All this talk of hockey and donuts very nearly makes me yearn for Tim Horton’s…Lord help me.
Some pipemakers contend that the round puck-ish resonator causes added turbulence. What’s that, you might ask?
Turbulence: fluctuations in air pressure caused by warm air rising from the Earth’s surface and cool air descending from higher elevations in the Earth’s atmosphere.
Or maybe it’s the other way around…Either way, I don’t know what it has to do with bass drones.
Can we talk some more about donuts now please?
The donut master /\
What Uilliam said. (with a few more stops for breathing )
I don’t have any input on the reg tuning pin, but for the bass drone regulator, I am wondering if this may possibly be for adding a bit of back-pressure. There is a small, barely noticible difference between having the resonator on versus nothing at all - too small a difference to care about. However, if you have the occasional bass drone reed that wants to jump out of tune at the change in pressure, you can cure this by increasing back pressure - just close off the end of the drone a little bit with tape or blue-tac or … a resonator.
djm
Let me start off by saying that I’m drawing upon parts of my brain that haven’t seen the light of day for years, but here’s what I remember about sound propagation, and possible effect of the hockey puck (“HP”).
If you project a sound into open air, such as from the end of an open tube, the sound energy radiates into 360 degrees of space. If you project sound through a hole in a surface (with the surface being the “HP”, or the bell of a trumpet), most of the sound energy is projected into only ~180 degrees of space, giving you an increase of a factor of 2 (~3dB) towards the intended direction.
There are other factors, such as frequencies propagated, and the diameter of the radiating surface. Since the “HP” is so small in relationship to the fundamental pitch (D2 ~73Hz), the frequencies “reinforced” will be the upper harmonics. This could be why some have expressed that the “HP” design gives a warmer sound, which would indicate higher prominence of harmonics. If you listen to live performances of Baroque era brass instruments (which have comparatively smaller bell areas than modern brass instruments), you notice differences that can’t fully be written off as differences in bore diameters compared to modern era instruments.
Any chamber within a “HP” would be effective in emphasizing a particular harmonic frequency since the volume within is well below the volume required to set-up a reinforcing standing wave for the fundamental frequency (D).
If anyone can point out where I may have left the realm of reality in my theory, or if anyone was able to make it to the end without snoring (or giggling), please let me know.
dave boling
well it IS broken (why the heck would i want to split it!!!) and its an ivory one too, (not imitation) …i suppose nothing can be done of it
And what the feckles is an M8?
Could it be computer speak for “mate”?
Rick
The hollowed out bass drone end pieces DEFINITELY affect the tone of the drone, but not all bass drone hockey pucks are hollow.
I can add a little hands on experience here.
Here are the facts I have found, and then some guesses about why other people do what they do.
When I made my drones, I made 4 ends for the bass drone. The first one was a purely decorative end piece, where there was no change to the bore on the way out. This had a nice buzzy, almost raspy sound.
Second, third and fourth I made end pieces that were tulip shaped but with larger and larger cavities inside the tulip, before returning to the same size exit hole as the bore of the end of the drone. Using the same drone and reed, just replacing the end piece, as the hollow cavity got bigger and bigger, the raspy sound gave way to a smoother sound, which I can describe as this: Make a “wah” sound very slowly. At first your mouth is mostly closed - that is the tone given by the end piece that I made with the largest cavity. At the end of “wah” your mouth is much more open and this is the tone given by the first end piece.
The hollow cavity at the end DEFINITELY affects the tone of the drone. I did not make the hockey puck shape, so I have no experience with redirecting the sound, but I like being able to clearly hear that bass drone even in a noisy situation.
Lastly, I have noticed that some pipes are made with hollow resonator hockey puck ends, whereas other makers give the same outside appearance but with no interior cavity.
So much for facts, now on to my guesses. My guess is that some makers make the hollow end bits for the tonal difference that they deliver because they like that sound. My other guess is that some makers make a solid hockey puck end piece because it does redirect the sound away from the player and/or because they like the look. Lastly, I guess that people like Kirk Lynch use unhollowed non-puck end pieces because it produces the tone that he likes and he likes being better able to hear his bass drone while playing.
ay m8 = mate
i’m going to see my…m8… tonight so ill get a good look at it again. i’ll see if there’s anything that is obvias i can do to fix it…although i must say, this is a job duct tape mite have a bit of trouble fixing…
well, we’ve got our self a dentist who’s going to fix it…
yes a dentist 
he’s got all the stuff to do it, and has done it in the past