Testing “Bessel vented” drums

Directly derived from the results in the lab, I built a set of chassis with varying air gap that are able to hold any type of top and bottom shell combination. Those chassis are holding all lugs and snare strainer, and most importantly are shaped in a way that the opened surface from the inside out follows a specific “impedance adaptation” curve for the best acoustical conversion.

This architecture is a major step towards “sound shaping” for demanding drummers in search of their personal sound. I have added a set of parameters that can be adjusted to tailor the sound very precisely : air gap, top shell and bottom shell can be changed independantly

I shot a video in my home studio to feature the effects of changing top / bottom shells using a 8mm air gap chassis, with 6 ply maple (4mm) shells of both 2 and 3″ height, resulting in 3 different sound characteristics.

Sorry for the very poor drumming skills.

The sound was recorded with AKG P17 overhead through blue tube preamp, and a AKG P2 kick , snare was close miked with a SM57 3-4 inches off the head, pointing to its center.

No EQ, Compression, Gate or any effect has been added for the purpose of this video.

Repercussion snares 8 mm







New R-evolution from R-epercussion

Finally ! it’s been months of design and calculation, the first 14×5″ proto is out and in the studio – Tremendous sound !

It features “Bessel venting” pushed to new performances, shells with absolutely no hardware nor holes, stainless steel lugs, Dunnett throw off. Top and bottom shells are alike (6 ply maple) on this one, but the architecture definitely calls for playing around with all type of shells and combinations …. soon !

Quick and dirty tuning showed incredible response, fantastic sound with snare off (as if the snare was 3x deeper) excellent playing range with great sensitivity, and tons of projection and sheer power presence.

Playing comfort is awesome, this is a really really easy instrument to play !!

Wanna test it ?

New concept soon out ! — r-epercussion.com

Finally ! it has been month of design, research of material, suppliers, and I am gathering at last all the parts for my next series of snare drums. Those will benefit from all the understanding we had in the lab relative to venting and global architecture. Just piling the various elements, this future architecture allows […]

via New concept soon out ! — r-epercussion.com

New concept soon out !

Finally ! it has been month of design, research of material, suppliers, and I am gathering at last all the parts for my next series of snare drums. Those will benefit from all the understanding we had in the lab relative to venting and global architecture.


Just piling the various elements, this future architecture allows for very thin an resonant shell, and infinite combinations of upper & lower shell, with the benefit of a super efficient ported radial vent.


Kudos to LVA students

Yesterday, june 24th, the final presentation of the snare drum study took place in the National Institute of Applied Science (INSA) Laboratory of Vibration & Acoustics in Lyon, France.

Congratulations to the students and teachers involved, the results are really a breakthrough in the understanding of the snare drums physics and gave some very interesting perspective in the perceptive domain.

More to come soon on repercussion website.

photo de titre

Subjective / Objective testing in the lab

Repercussion is currently testing a set of prototypes among a number of hi-end snare drums. The work includes binaural recording and re-listening to understand the characteristics of the sound produced and how they relate to the players appraisal.

The outstanding sound quality of Bessel Vented Snares from Repercussion will soon be objectively understood !


History of mankind in one instrument

Back in 2011, I left Romania with a heavy heart. My fantastic team offered a typical Romanian instrument traditionally played by Gypsies named “Tsambal”. I got in in working condition through a local maker.

A Romanian Tsambal

Then an Iranian friend took a look and said “that’s like a santur”, and If I asked someone from greece it would be “santouri”, and in India it would be santoor…Here in france it is called “Cithare” although all of those instruments are based on the same principle of hammered strings, their shapes, tuning and resulting sound would of course be different.

Back to this Tsambal, and to the history of Gypsies : why is this instrument so similar to what can be found in India or in Iran (among all surrounding countries) ? Because it has followed the migration of nomad Manouche (“free man” in Sanskrit) and Roms People, from northwest india to Iran and among all courtships where their musical talents would come upfront.

Because they went through what was called the “little egypt” in greece they were nicknamed “gypsies”, then some of them played their instruments in the Bohemian region, where they obtained a pass and were then nicknamed “Bohemians”.

Those people are the last living evidence of about 6000 years of mankind, when at the time all mankind was nomad. So it is not just a musical instrument I was offered, but a piece of mankind history. If you have the chance to read about those people story, do so you will simply learn about the history of man.

Shell contribution

At last ! I was personally waiting for those kind of results for a long time, and this is just the first ones out of the lab. The question asked here is : what would be the contribution breakdown between shell radiation and head radiation in the total sound of a snare drum ? The curves above show, for a snare played in an anechoic room, the vibration spectra (FRF to be precise) of the top head (red curve), bottom head (green curve) and vibration at two location on the shell. No surprises, below 1500 Hz (try out to filter a snare sound hi passed at this frequency you ‘ll realize you have lost quite some sound) the heads are way above the shell (we are talking a factor 10), and this would be a factor 1000 below 750 Hz…The snare used for this test is a hi-end instrument 14×6,5 Mahogany shell (with reinforcement rings, so not exactly the hardest shell you’d find ou there)….

More to come in the next weeks.