Bass Bone PVC Extension?

[trombinstharry]

Good evening fellow trombonists, I have been playing on an old king bass trombone that belongs to my school and personally, I dislike the valve tuning. Of course, it is a Bb bass trombone with two stacked valves tuned to F and E. Yes I do understand that this is not uncommon but I think that this trombone could be put into F and D. First of all, is it common to see F and D dependent valve configurations? And, how could I achieve this? I was thinking that I could get PVC pipe and apply it to my second valve tuning slide but I was worried it would make my second valve sound worse. Is this a good idea or should I go a different route?

[JohnL]

F/D is pretty much the standard tuning for modern dependent-valve bass trombones. I would not suggest trying to use PVC, but, if you really want to try to do something on your own, I have heard of a few people who used copper tubing available from some well-stocked hobby shops.

There are D extensions out there for the Duo-Gravis, but I doubt if you want to spend that kind of money on a horn you don't own.

[Matt K]

You probably have a "Duo Gravis" or 6B. The default configuration was a #Eb I believe but all the ones that I've owned had a D extension on them. It was much, much more common to have an E or Eb 50~ years ago but most of the time you'll see F/D now.

Unfortunately, because of the way the rotors are configured, you'll likely have to have at least a few pieces fabricated. (Note that if you were to extend the tubing you currently have, it would have to go through the F attachment tubing.) Basically to get around that, you'll need to gentle curves to bring it either in front of or behind the F attachment tubing and long enough to extend it beyond the main tuning slide. The cheapest option would be to contact someone who has done the work before and ship your horn there unless someone local to you is confident enough to bend tubes for it. Probably looking at a couple hundred in parts + labor.

Well, actually, technically the cheapest would be to find someone who has a spare or isn't using theirs but sine most people use t, your chances are exceedingly slim and you'd have to be very patient.

[BGuttman]

Back in the Bad Old Days a flat E 2nd valve was the way we used double valve bass trombones. You can play all the notes on one. Granted they won't be as convenient.

If this is not your instrument I wouldn't spend a penny on modifying it. Instead, save your money so you can buy one of your own that works the way you want. If the school wants to invest in a set of tubes to make it Bf/F/D, great. Such tubes exist.

PVC wont sound right as an extension. Nor will rubber, Tygon, or heater hose. But if you want to play, have fun. Just don't expect a good outcome.

[trombinstharry]

Where would one go about purchasing a new set of piping for my 2nd valve? I looked into my trombone and it is an early 70s Duo Gravis 6b. Could I order a D tuning slide from King?

[BGuttman]

Why do you want to spend a nickel on this trombone? At the end of the year you will have spent $400 for some tubes you can't use on anything else. If you can get the school to buy the tubes, that's fine. I don't think King sells them any more, but I'm sure you could locate a set. Note that the tubes will adapt to Eb and also to D.

As I mentioned above, don't spend a nickel of your own money on this. Instead, save up and buy a horn of your own. You can get a Wessex Tubas copy of the King 7B for about $1000 new. And it's all yours.

[Matt K]

It is possible OP is trying to get the school to pay for it.

Where would one go about purchasing a new set of piping for my 2nd valve? I looked into my trombone and it is an early 70s Duo Gravis 6b. Could I order a D tuning slide from King?

That's as I expected, so my initial comment stands: you'd either have to go second hand for the existing part (which means you'll probably have to be quite patent) or you'd have to have someone fabricate one for you. There are a couple of techs on the forum who could probably take on the project. Bruce's estimate is probably around the ballpark for what it would cost to have one fabricated. You'd have to ship the bell section --- probably looking at ~$100 in shipping too. Unless you can find pre-bent tubing that will fit the existing valve, in which case you might be able to have a local person do it. Usually band repair shops aren't as interested in taking on custom work like that, but some are so it can't hurt to ask - they may even do it for less than that if the school is the one paying for it since they may do a lot of other work for the school.

Remember that the bore of the tubing for the Duo Gravis is .562, which is usually the same size as that of a tenor trombone. That does mean you can probably source tubing a little more handily but it also means less existing bends might be available. (It looks like one of the bends on a thayer valve for the G wrap might work but it looks like the one on the F loop isn't the right angle).

For reference, someone took some really good photos of their Duo Gravis. Note how the tuning slide needs to be quite long, so it bends in front of (or behind, they are actually usually able to be swapped for whatever your preference is). Another good picture of the bends that you need. (Oh hey, here are the pictures of my old Duo Gravis: https://drive.google.com/drive/folders/ ... sp=sharing)

There was actually one for sale it looks like not too long ago: https://www.ebay.ie/itm/d-slide-extensi ... 4#shpCntId That would be the exact part that is needed.

Now, you could potentially use other bends too; that's just the official King part. I've seen some souped up Duo Gravis before... one with 4 valves like a Cimbasso! The tech who does the work might have something on-hand that can be used... or can acquire but the simplest solution is probably something that looks very similar to the 'sleeve' like the official King part because you should be able to use your existing crook in it.

Hopefully you can get something that you're looking for. Bruce's recommendation about some of the clones is also good. You'll drop a decent amount of money on this project and for a little more you could own your horn. I would caution you about horns that are under $900 or so... some are hit or miss. The Wessex or Mack Brass are about the cheapest dealers that consistently get good marks. Cheaper and you hear fairly mixed reviews about the outcome.

[jpwell]

It’s not a complicated process. Buy two S bends, a 90 bend, some ferels and some tubing. I think my repair guy got them from kanstal. Solder and fit together so you extend the Eb slide. My DG is excellent with the bigger slide.