The subjects in every students mind is usually the A clarinet, you know the one your teacher had with the double case and the cover and all the rest of it, and if you are too young or old to know or remember, well there is a much better solution to trying to match or even afford a good A clarinet.
I happen to have really a superb one, best I ever played and I got it for practically nothing, but I have even a better, less expensive one for your consideration:
Use your Bb and play everything on one clarinet!
Does this sound ridiculous? It is not, and is the best solution and you will be dragging around much less weight.
The only thing you need will be a clarinet with a low Eb, which is a good idea in any case.
That implies the purchase of a full boehm instrument, also a good idea becasue it is simply easier to manipulate in virtually any or ankind kind of tonality or non-tonality.
The configuration is simply the wonderful articulated G#, which means the ability to trill from F#-G# with great faility and with the correct fingerings, instead of having to sweat certain configurations.
The third ring facilitates this as well as giving you the beautiful one and three (ring) fingering for Bb/Eb.
I played these kind of clarinets for years and years, the full-boehm Mazzeo clarinets, however the Mazzeo mechanism, difficult to come by these days, is not necessary.
The biggest advantage is ease of manipulation already mentioned.
I am totally serious, so for those of you who are looking or wondering about A clarinets, or C, for that matter, just play it on one clarinet.
No, you cannot play Eb clarinet parts on the one clarinet, they are too high if they are written for Eb clarinet.
But for that A clarinet, get a full-boehm Bb and relax.
For those of you who are conversant with the repertoire for orchestra, I once played in a major concert, the “Pines of Rome” the A clarinet big solo that finishes with the recording of a nightengale, by Ottorino Respighi. I played on my Bb full-boehm Mazzeo clarinet, and it was a ball. It was probably the only time it was ever done, but I it is easier than the A clarinet part.You know, getting the right reed, practicing it for hours for the legato and worrying about your low E being flat, which inevitably it is (was). Of course, if the conductor can really hear and asks for the other horn, well that is another story, and perhaps another orchestra.