Shepard tone illusion

[Glenn]

Just spotted this (rambling) video on Reddit about the Shepard tone illusion with the accordion bass (Stradella). It’s an interesting subject and one which we all subconsciously make use of when playing and arranging. Do any of you notice how the registers you select in the bass effect how you perceive the smoothness across octaves?

 

[debra]

Just spotted this (rambling) video on Reddit about the Shepard tone illusion with the accordion bass (Stradella). It’s an interesting subject and one which we all subconsciously make use of when playing and arranging. Do any of you notice how the registers you select in the bass effect how you perceive the smoothness across octaves?

Interesting but indeed very rambling instead of getting straight to the point... This 12 minute video could have been done better in under 3 minutes...

I do consciously take octave jumps into account when arranging music, more so for accordion orchestra than for solo accordion because the Stradella bass side does its best to hide the octave jump whereas a bass accordion (used in ensembles) does not. Many people who arrange music for accordion ensembles or orchestras essentially do not know the possibilities and limitations of the bass accordion and as a result a lot of the arrangements even from well-known (mostly German) arrangers have poor bass accordion parts. Essentially it takes an experienced bass accordion player to write good arrangements for accordion orchestra. (And it also takes good bass accordions with good amplification, not the junk used in many orchestras, especially junk in amplification, not so much in the bass accordion itself.)
What arrangers forget is to add octaves to hide the jump, like going A-G-F-E+E-D-C to go down with a jump around the E (meaning the following D is in the octave above that F). They also often forget to add octaves to the very lowest notes when needed to compensate for the slow reed response of these notes. They also often just copy a line written for Cello or Double Base or a combination of these two without taking the range and the response of the bass accordion into account...

The octave jump is also very important for the chords used on Stradella, something the video ignores completely. Hiding the octave jump helps to also keep the chords playing in roughly the same range, and this is where the weak point is of playing Stradella on some convertor instruments, not really designed to have good Stradella bass. On my bayan the chord of D sounds too high and that of E sounds rather low. Neither is ideal.

 

[TomBR]

[Paul posted while I was writing, but Ill leave as was.]
Thanks Glenn, yes rambling, but enjoyable video.
Pure Shepard tones here, for reference

Multi-octaves in stradella bass chords are just crucial for keeping the inversions under control since everything is coming from single-octave sets of chromatic reeds.

Even if one cant actually play piano keyboard, I think some playing on a piano or electronic keyboard is really interesting as a way of exploring the significance and effect of chord inversions.

I understand that more sophisticated electronic and arranger keyboards actually follow appropriate chord inversions in their guitar emulations. Interesting and significant that this was considered worthwhile.

 

[donn]

Do any of you notice how the registers you select in the bass effect how you perceive the smoothness across octaves?

Well, sure. The combined register manages to avoid perceptible octave jumps, but the other two dont. So if I choose the single bass register, choice of key matters a good deal. Chromatic button offers a choice of congruent keys, where I might be better off playing a tune in A or Eb than C, if there are any bass runs that would fall apart.

[I might add, that when I use that single bass register, one of the dancers can pretty much be relied on to say something about sounding like a calliope. It occurs to me that the occasional unplanned octave jump might add a certain surprise factor to the music that to some degree compensates for the broken musical line.]

I dont know if thats Shepard - I skipped the video, but reading about the term on wikipedia, it seems to depend at least in part on modulation of the volume of the component notes, and it seems unlikely to me that stradella bass mechanisms do any such thing.

 

[Eddy Yates]

My apologies in advance, but is there an accordion made to specifically play bass parts in an accordion orchestra, or is it just a regular accordion playing bass parts?

 

[jozz]

they are specialized: fatter and only treble side

Hohner Basso is an example

 

[jozz]

10 hour Shepard tone illusion :



:mrgreen:

 

[debra]

they are specialized: fatter and only treble side

Hohner Basso is an example

And they typically start at C1 (where melody bass on 99% of the convertor accordions only goes down to E1).
In terms of sound I really like the Bugari bass accordion, but in terms of possibilities I prefer the Pigini P39 or C39 which has 3 reed sets and registers (L, LM, LH, LMH). Most of these bass accordions nowadays have 39 notes, from C1 to D4 (Hohner only 37 from C1 to C4 I believe) and the Pigini C39 actually has 40 notes (C1 to Eb4) and believe me, I do use that 40th note regularly!

 

[Eddy Yates]

Excellent! Are there any YouTube or other recordings? I have done a few searches and can’t find any. Is the Basson Accordion the same thing? Thanks.

 

[debra]

Excellent! Are there any YouTube or other recordings? I have done a few searches and can’t find any. Is the Basson Accordion the same thing? Thanks.

(I know we are going off-topic here...)

The term basson is often used (mostly by the Italian manufacturers) to refer to a bass accordion.
There are very few solo bass accordion performances that let you enjoy just this instrument, but I happen to have one:

which was recorded live during a concert. It is played on a Pigini C39 bass accordion using just the L register.
It is a recording of Bachs Cello suite nr. 1 (first movement) which is normally in G major but that then requires going up to the note G4 whereas my bass accordion only goes up to Eb4 (the highest of any bass accordion I know) so the piece was transposed down to Eb major.
I turned this piece together with Gounods Ave Maria into a new composition for bass accordions, three accordions and a percussion instrument (cajon, bongos or djembe) and have a recording of that: https://www.de-bra.nl/muziek/Ave Cello.mp3 from the Van ARTE CD by accordion quintet ARTE (in which I play the bass). This composition is in G major.

 

[jozz]

I turned this piece together with Gounods Ave Maria into a new composition for bass accordions, three accordions and a percussion instrument (cajon, bongos or djembe) and have a recording of that: https://www.de-bra.nl/muziek/Ave Cello.mp3 from the Van ARTE CD by accordion quintet ARTE (in which I play the bass). This composition is in G major.

nice job! very tasteful

 

[Eddy Yates]

Thanks, Paul! Lovely. Sorry to go off topic, but I didn’t find anything else on the forum or the web.
Almost makes me want to learn the buttons.....