I notice that some players switch leadpipes in order to change their sound, which raises some questions. Which shapes produce which timbres? Since manufacturers match leadpipe tapers to bell tapers to produce a desired sound, would switching leadpipes sometimes result in an undesirable outcome? For instance, can a desired change in timbre be accompanied by intonation problems with partials? Or, for another example, could improvement in response be at the cost of sacrificing a resonant timbre? Many other variations can occur as well. Is there any rule of thumb regarding exchanging leadpipes and possibly predicting results, or is this more likely a matter of trial and error? And what about changing mouthpieces to optimize a leadpipe change?

Try em and find out. It's not really a science, after all- it's all trial and error.

There are so many mouthpieces, tuning slides, and leadpipes by very reputable makers, this is a sign for me that these components must be working for <I>someone</I>.

Aidan has a nice Youtube video about what it means for a horn to be "stock," and why there's even such a thing: basically, manufacturers need to be able to make money through scale, and therefore need to sell horns that work reasonably well for their intended market: They necessarily aim for the "middle of the fairway", musicially speaking.

I have never been able to look at a leadpipe are even guess as to how it might respond, and often from looking at two different ones from the same maker, struggle to even see a difference: What helps me in deciding on components is 1) to know how I want to sound, in a general way, and 2) understand my natural tendencies, and find pieces that make making the sound I want easier, even if just marginally so.

Since manufacturers match leadpipe tapers to bell tapers to produce a desired sound

While that is a reasonable assumption, do note that most of the so-called "boutique" manufacturers, and even some of the high-end mass-manufactured instruments (e.g., Yamaha), frequently offer multiple leadpipe options as a standard now.

A leadpipe swap can definitely be worse than whatever the "stock" pipe is, but OTOH one of the "rules of thumb" is that for any given bore size, a "2" pipe is often pretty safe. Especially as a "starting point."

There are other reasonable generalities. A horn that is similar to a Bach 42 often works well with a 42 replica or a 1.5 in Shires terminology. A horn that this similar to an 88 often works well with an 8/88H replica or something closer to a Shires 2.5. Is that always true? Nope! There are so many variables that it's hard to keep track of them. If you do swap the pipe, have something to compare it against, and if it works better for you, work from there. The typical "boutique" pipes make this pretty straightforward because you can fairly easily compare the numbers, e.g., if a 2.5 works better than a 2, a 3, or 2.5L/S is a good logical "next choice" to try. Keep going until you've spent more money than you want to or when continuing to go in the same "direction" makes it worse!

Some pipes tend to work well on a lot of makers' horns. The "2", as mentioned, is one of those pipes. The Brassark 32H replica has worked well in basically everything I've dropped it in. I've found that a 52H pipe is brilliant on every 525 I've put it in. Quite possible that these observations are purely coincidental too! How's that for a non answer?

Glad I read this thread: Having changed to a much larger mouthpiece for my Edwards T-350 (since I mostly play bass these days), I decided to revisit my leadpipe selection (from the three I had, unfortunately all unmarked), and determined that one of the others works better (speaks more clearly).

[quote="JTeagarden"]Glad I read this thread: Having changed to a much larger mouthpiece for my Edwards T-350 (since I mostly play bass these days), I decided to revisit my leadpipe selection (from the three I had, unfortunately all unmarked), and determined that one of the others works better (speaks more clearly).[/quote]

If it's an Edwards, the markings are the # of knurls in the threads on top:

One Groove + Two Ridges = T1 or B1 (smallest)

Two Grooves + Three Ridges = T2 or B2

Three Grooves + Four Ridges = T3 or B3 (largest)

Thanks, I thought there was a trick to it...

damned if that didn't work! I'm using the T1...