Top felt pad/wingnot was removed and a mixture containing small diameter and thin rubber disc/ring placed on top surface of cymbal center concentric with mounting post/thread, and top felt pad and wingnut not refitted.
Experiment was with a professional drummer who used one or two sticks and played all over the surface of the cymbal and at varying intensities.
He could not get the cymbal to go into chaotic/harsh/ear bleed mode despite his best efforts.
All present agreed that the sound produced was cleaner, clearer and more pleasing than the usual sound produced, and numerous A/B comparisons were trialed.
The position, weight/mass/damping and contact area of the rubber pad are seemingly not sufficient to produce the effects observed.
Dan.
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Experimentation with small patches of duct tape on the underside of cymbals is not uncommon. It's a trial and error process, but often can result in a preferred sound. Then you can mic it and use an op-amp preamp, of course.
On the other hand, some may feel that op-amp preamps can be a little too honest with some cymbals. If one goes to a large music store with many cymbals on display, it is possible to do some test listening to whatever is available. Most do not have the nice smooth shimmery sound found on many nice sounding records. Tube preamps with transformers, compressors with tubes and transformers, etc.,are often used to result in what some would consider to be a preferable timbre. In such a case, the problem with op-amps is they don't distort the signal the way someone would like. The design of equipment that distorts euphonically is often analogous to the duct taping of cymbals -- a lot of trial and error is involved. We could actually use more refined engineering capabilities in this area of design, maybe even find a way to better use op-amps to achieve good results. So far, people have only gotten pretty good at figuring out how to use certain op-amps in guitar distortion pedals, which is a similar application to things like cymbals and vocals, but the latter require more subtlety and sophistication. That's a problem we still have if we want to use more op-amps for certain types of applications.
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Yes, but minor.
The centre and quite inactive part of the cymbal rests on a felt pad.
Resting my disc on the top surface of the cymbal should not effect any significant mechanical change, however the result was distinctly audible.
Dan.
Mark,
You will typically find that the designers of software plugins for digital audio workstations, trying to emulate 'tube' sound or for instance the Aphex Aural Excitor in software, have done a deep study of what it is that makes these things sound nice. But it is probably proprietary.
Also plug-ins for say Leslie speakers and EMT echo panels has received a lot of effort, but again, probably proprietary.
What I am saying is that there are many smart guys around that really know what it is that makes a tube pre sound like a tube pre etc.
Jan
Fairly dramatic change of boundary conditions to the vibrating disk problem. See cymatics for instance.
This stuff is also commonly used to tune/dampen drums and cymbals, but is not the effect I am talking about.
Cymbals are very personal, every drummer I know has his store selected preferred and favorite cymbals, and yes some are clean/nice sounding, and some are downright nasty sounding.
Mic/eq/preamps are everything when it comes to PA systems, and it's a real fine line between pleasing amplified cymbals and sound that slices and dices one's ears every hit.....tinnitus anybody ?.
Agreed, some opamp preamps don't sound right and it's not a case of 'honesty' so much as 'chaotic' input/source sound causing more 'chaos' at the output.
Input a clean cymbal and the output can be pretty nice, input a noisy/chaotic cymbal and it all gets nasty real quick.
Tube/transformer stages don't suffer this effect in the same manner/degree and that is their worth and appeal.
CD vs Vinyl is another example of digital stage HF noise causing unpleasant throughput.
Dan.
Yes, I have been following developments in plugins for years. Most sound digital, it seems very difficult to properly emulate good analog. Crane Song Prism is a good one, so is UAD Plate Reverb, but they are some of the best, and they do still sound a bit digital, but if used judiciously they can sound good. I still use outboard gear for best results, and the good stuff is unfortunately expensive, forcing one to make hard choices. I suspect we could do better with modern analog design at lower cost, and that there would be a market for it. Op-amps would probably play in important role. Also, we could use better modeling of magnetics. A lot of work has been done on such modeling for switch mode power. The codes that have been developed for that have been used to model distortion in telephone line transformers, but only accurate to about 4 db for 2nd or 3rd order harmonic prediction, according to one paper I read. Way too far off for pro audio use.
It is impressive the efforts put into emulating classic 70s synths and getting all the foibles modelled.
Dan
As you can see, no part of the cymbal is “quite inactive” with all these modes of vibration taking place.
As a supplemental info, from industrial inspections with ultrasonic waves, a small oil drop on an inch wide surface of a 1/16 inch thick metal piece can attenuate (damp) the propagated shear waves by about 20dB and the surface waves by about 40dB.
George
Attachments
I would really like to read an insider’s view on this.
I’ve made a wish, who knows?
That's a tall order, I can give a few. The non-audio applications were all driven by performance numbers, input precision (noise, etc.) and THD or SFDR.
797 was designed for Teradyne (ATE) and of course general purpose instrumentation. They needed to start testing hi-res DAC's and ADC's.
AP and Stanford research use many too. More got into audio than I thought.
743/45 was for sonar (cold war ended), ended up doing a full generation of CT at GE. No meaningful presence in audio except DIY.
Some xDSL drivers got some second life as headphone drivers actually in the 10's of million pieces.
That is a completely different statement from what you said at first.Max headroom said:
When there is just sufficient nonlinearity to allow for chaotic behaviour you might only need to reduce the nonlinearity by a very small amount to kill or modify the chaotic behaviour - that is one of the reasons it is called chaotic! So "I changed the system just a little, and the chaotic behaviour changed a lot" - who would have thought it?
The AD797 is a very good product, especially for instrumentation. Whatever normal instrumentation measures is OK with the 797 in the thru-path. However, Richard Heyser warned me that test instruments could have potential problems in measuring ALL deviation, whatever the problem is, because of the internal devices used. So, an IC might have trouble measuring itself, you might say.
Thanks both you and George, point taken, though I still reckon the effect is not solely due to mechanical damping of the cymbal at the center, which is already placed on a damping felt pad.
I may be proven wrong into the future, that remains to be seen.
Back to opamps.....
Dan.
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Great device for a DC servo, especially with an external trimpot.
http://www.analog.com/media/en/technical-documentation/data-sheets/AD743.pdf
Output voltage drops after 300 Hz; 60 dB CMRR at 20 KHz, 40 dB open loop gain at 20 kHz
Still, a couple of vacuum triode stages are better for audio.
http://www.analog.com/media/en/technical-documentation/data-sheets/AD743.pdf
Output voltage drops after 300 Hz; 60 dB CMRR at 20 KHz, 40 dB open loop gain at 20 kHz
Still, a couple of vacuum triode stages are better for audio.
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Thanks for the history sample.🙂
I have already suspected why you are reluctant to go into this.
It will make for a very dull story. No drama 😀
George
And I was looking at the AD745 for a transformer input microphone preamp. 10,000 ohm input impedance sweet spot and enough output power to drive a line. FET inputs seem to have less trouble with EMI.
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