davewantsmoore Posted February 18, 2016 Posted February 18, 2016 I never knew listening to music was so complicated , put some on, relax and enjoy. It's not .... But designing equipment can be
davewantsmoore Posted February 18, 2016 Posted February 18, 2016 Think about it; high gloss, hard, thin, shiney surface verses soft, thick, heavily stippled surface. Which do you think will refkect sound better? I appreciate the logic Based on my own tinkerings even something substantially more absorbent (than soft textured paint) produces a response change which is exceedingly small. You need even ~1cm thick foam to make a difference close to a tweeter. I would not argue (I'd be interested) if you saw an actual (v. Small) change in the response .... But something clearly audible raises questions
davewantsmoore Posted February 18, 2016 Posted February 18, 2016 Don't get me wrong measurement is an essential tool but in the above we have a perfect example of peoples ears telling them something they know is there. But there is a whole book full of reasons why we hear things which aren't there. It is wise to confirm the response is actually different before trying to listen to the difference. Lest it is not there, and confirmation bias ensues. Somewhat reverse example. .... If I build two bridges and painted one red and one green .... and then timed how long to drive over them... And concluded red bridges are faster to drive over. It would look a bit silly if one bridge ended up being 100m long and the other 130m long.
davewantsmoore Posted February 18, 2016 Posted February 18, 2016 Sound waves are quite long particularly compared with light. The surface barely reflects light it's absorbing effect is even stronger with sound. Wut ?!
Newman Posted February 18, 2016 Posted February 18, 2016 If you're using ratios of wavelengths as an analogy it does matter. 10kHz as an acoustic wave is only 3cm, but as an E-M wave it's 300,000 metres. Let me repeat my initial post that you are having trouble with: "Think about it" the other way around: multiply the stippled surface roughness by the ratio of light wavelength to sound wavelength (about a million to 1), and the Houston Finish looks like glass to a sound wave. Normal visible light has a wavelength about one millionth of the wavelength of audible sound. Let's say 100,000 to one for the highest audible frequencies. Now, a 'mirror finish' on a metal or paint surface has a surface roughness of about 0.00013 mm (using a surface finish chart). Light waves reflect off that pretty well and show a nice reflection in the surface. The equivalent 'mirror finish' to a 10 kHz sound wave is 100,000 x 0.00013 mm = 13mm. So if the Houston Stipple Finish is 13mm rough, it will reflect 10 kHz like metal or paint polished to a mirror finish reflects light. Okay, the numbers and ratios are very approximate. But the general point is there. And I only wanted to make a general point.
Slartibartfast Posted February 18, 2016 Posted February 18, 2016 Let me repeat my initial post that you are having trouble with: Normal visible light has a wavelength about one millionth of the wavelength of audible sound. Let's say 100,000 to one for the highest audible frequencies. Now, a 'mirror finish' on a metal or paint surface has a surface roughness of about 0.00013 mm (using a surface finish chart). Light waves reflect off that pretty well and show a nice reflection in the surface. The equivalent 'mirror finish' to a 10 kHz sound wave is 100,000 x 0.00013 mm = 13mm. So if the Houston Stipple Finish is 13mm rough, it will reflect 10 kHz like metal or paint polished to a mirror finish reflects light. Okay, the numbers and ratios are very approximate. But the general point is there. And I only wanted to make a general point. I don't have a problem with your general argument. Obviously, the finish will have no audible or measurable effect. What I did have a problem with was your analogy, which compares wavelengths in different media travelling at different speeds. It unnecessarily confuses the argument.
Slartibartfast Posted February 18, 2016 Posted February 18, 2016 The equivalent 'mirror finish' to a 10 kHz sound wave is 100,000 x 0.00013 mm = 13mm. So if the Houston Stipple Finish is 13mm rough, it will reflect 10 kHz like metal or paint polished to a mirror finish reflects light. Okay, the numbers and ratios are very approximate. But the general point is there. And I only wanted to make a general point. The only thing to add would be that as little as 0.25 of a wavelength could introduce an interference / diffraction effect that would be measurable, but that's still about 100 times larger than what we're talking about here.
Newman Posted February 18, 2016 Posted February 18, 2016 Good. It's furious agreement. Sent from my HTC_0P6B using Tapatalk
thermonicavenger Posted February 18, 2016 Posted February 18, 2016 (edited) Yup Dave valid point. But there are some things every speaker builder I have ever talked to agrees on this point. There is a difference between the sonic signature of a coated/painted/laquered speaker box and a un coated/painted/treated one. Conclusions either we have collectively all deluded ourselves or we are correct. I have the advantage of seeing laser spectrometer vibration graphs for this issue so I know. The only situation it may be a mute point is with a granite,cement or Magico enclosure where treated or untreated is irrelevant due to the initial rigidity & inert nature of the enclosure. BUT... I'm only summising here I don't actually know Edited February 18, 2016 by thermonicavenger
davewantsmoore Posted February 18, 2016 Posted February 18, 2016 Let me repeat my initial post that you are having trouble with: Indeed. Any 'stippling' or roughness on the surface ... ie. the 'shape' .... is completely a red herring, The absorption qualities of the surface is where an effect could be had, the surface sound need to be softer than thin felt, for example.... to have any type of measureable, let alone audible effect. But there are some things every speaker builder I have ever talked to agrees on this point. There is a difference between the sonic signature of a coated/painted/laquered speaker box and a un coated/painted/treated one. I'd be interested to see a measurement of the effect ..... it's trivial to measure even things which are nowhere near audible .... so it's not a huge task in that respect. The BIG task is keeping the method rational, as many things will affect the measurement if you're not very careful (speaker location, v. small difference between an A and B speaker which aren't to do with the coating, mic location, etc. etc.) ....... If I could have back the time I've lost on things like this, I'd be wealthy (thinking that measured/audible differences were due to X which I was intentionally changing ..... only to find it was caused by something else unexpected that I should have been controlling). >_<
davewantsmoore Posted February 18, 2016 Posted February 18, 2016 I have the advantage of seeing laser spectrometer vibration graphs for this issue so I know. Ah... but we were talking about absorbing a reflection. ..... my own accelerometer tests show that coatings, even ones more significant than paint (eg. epoxy resin) don't have a particularly significant affect, on a reasonably well braced wooden enclosure. (OTOH bracing makes an big difference). However the data isn't calibrated to any absolute value (it's only relative), so cannot be compared to anything else. 1
Sub Sonic Posted February 18, 2016 Posted February 18, 2016 (edited) I think the difference lies in the physical characteristics (mass etc) of paint changing the natural resonance of the panel in response to the sound as opposed to the idea of the surface finish affecting the sound waves reflected off it. Edit: Dave got in first, as usual :-) Edited February 18, 2016 by Sub Sonic
davewantsmoore Posted February 18, 2016 Posted February 18, 2016 I think the difference lies in the physical characteristics (mass etc) of paint changing the natural resonance of the panel in response to the sound Could be. The box would need to be not particularly solid though (no bracing and/or thin).
thermonicavenger Posted February 18, 2016 Posted February 18, 2016 (edited) I know what I know. I'm not going to waste time convincing others who will not accept it. It will not change what I know and do not feel the need to justify established fact. If you want the evidence contact GTD@bettanet.com.au & ask. Incidently I consider any one who is not amazed at the intricacy/complexit of his own ear/brain combo & considers a glorified electronic ruler superior is truly tragic and to be pitied above all men. When any of those superior instruments can conduct an orchestra in perfect time accent & pitch be sure to let me know. . Edited February 18, 2016 by thermonicavenger
mwhouston Posted February 18, 2016 Author Posted February 18, 2016 (edited) I don't have the time to DIY so i have picked up s/h Zu's and love them. I'd love to try some of these http://puremusicgroup.com/cart/index.php?_a=viewProd&productId=471 even though i dont have the $$ mabe Zu druids instead. I would have followed you to the Zoo (Zu) but I have read some negative reviews and now I'm wondering if the carnival of the animals may be better played out some where else. My 15" Beymas roar like lions from a 2.6W flea power. Edited February 18, 2016 by mwhouston
mwhouston Posted February 18, 2016 Author Posted February 18, 2016 Ah... but we were talking about absorbing a reflection. ..... my own accelerometer tests show that coatings, even ones more significant than paint (eg. epoxy resin) don't have a particularly significant affect, on a reasonably well braced wooden enclosure. (OTOH bracing makes an big difference). However the data isn't calibrated to any absolute value (it's only relative), so cannot be compared to anything else. Meaningless banter. You are better than this dribble. 2
mwhouston Posted February 18, 2016 Author Posted February 18, 2016 I know what I know. I'm not going to waste time convincing others who will not accept it. It will not change what I know and do not feel the need to justify established fact. If you want the evidence contact GTD@bettanet.com.au & ask. Incidently I consider any one who is not amazed at the intricacy/complexit of his own ear/brain combo & considers a glorified electronic ruler superior is truly tragic and to be pitied above all men. When any of those superior instruments can conduct an orchestra in perfect time accent & pitch be sure to let me know. . Only the very wise know what they don't know and would never inflict that on others. 1
thermonicavenger Posted February 18, 2016 Posted February 18, 2016 (edited) No one can inflict anything if it is not recognised or accepted. I know so if no one aside from all my friends and audio peers concurs I simply don't care. Edited February 18, 2016 by thermonicavenger 1
Newman Posted February 18, 2016 Posted February 18, 2016 Incidently I consider any one who is not amazed at the intricacy/complexit of his own ear/brain combo & considers a glorified electronic ruler superior is truly tragic and to be pitied above all men. When any of those superior instruments can conduct an orchestra in perfect time accent & pitch be sure to let me know. The only reason we measure with the assistance of any instrument is because it does one special thing better than we, unaided, can. That's the only reason we design and build instruments. No need to get all defensive about the good old ear/brain. It works up to its many limits, and we have some very useful instruments to help us beyond that. Refusing to use them, or learn from what they tell us, is like refusing to use telescopes to learn about the galaxies, and your demand that an audio instrument has to be able to conduct an orchestra before you will pay attention to what it reveals, is like insisting that a telescope has to be able to write a poem to the moon before you will admit it has anything to reveal beyond the unaided eye looking to the sky. 3
davewantsmoore Posted February 18, 2016 Posted February 18, 2016 (edited) Gah. Tapatalk app >_< Edited February 18, 2016 by davewantsmoore 1
davewantsmoore Posted February 18, 2016 Posted February 18, 2016 I still don't even really know exactly what the finish you are talking about is, aside from its thick. So I guess you're right. Anyways. Back to regularly scheduled programming. 1
mwhouston Posted February 18, 2016 Author Posted February 18, 2016 I was going to paint my new 170ltr boxes then realised I can't move them by myself. So I'll get the paint today and my assistant and wife to help me shift them into the garage. Generally I can get undercoat and top coat on in a day. A day or two later I can reassemble the boxes. In the meantime losts more listening. I really am enjoying them. 2
DAMO 1147 Posted February 18, 2016 Posted February 18, 2016 I would have followed you to the Zoo (Zu) but I have read some negative reviews and now I'm wondering if the carnival of the animals may be better played out some where else. My 15" Beymas roar like lions from a 2.6W flea power. I have great fun at the zoo but they suit me. After actually hearing them most of my original concearns (i had from the negative reviews) washed away. Relative to the s/h price point i have had no complaints. I recently upgraded tweeter to Omen mk 2 specs and that has provided improvemnts. I'm not comvinced they are any better than a really good DIY build especially when you look inside them. However i'm time poor, so I pay what i can to have Zu crew iron out bugs and do the hard lifting! They really suit me and my set up. on the whole stil verry happy with them and the Audion sterling amp. I'd like to up my sourCe gear if possible $$ wise in the future. I keep swaying between upgrading my source and uping the speakers to druids on a weekly'daily basis. have fun and love my HES's Damo 1
mwhouston Posted February 18, 2016 Author Posted February 18, 2016 I have great fun at the zoo but they suit me. After actually hearing them most of my original concearns (i had from the negative reviews) washed away. Relative to the s/h price point i have had no complaints. I recently upgraded tweeter to Omen mk 2 specs and that has provided improvemnts. I'm not comvinced they are any better than a really good DIY build especially when you look inside them. However i'm time poor, so I pay what i can to have Zu crew iron out bugs and do the hard lifting! They really suit me and my set up. on the whole stil verry happy with them and the Audion sterling amp. I'd like to up my sourCe gear if possible $$ wise in the future. I keep swaying between upgrading my source and uping the speakers to druids on a weekly'daily basis. have fun and love my HES's Damo Do you have an image of the Zu model and what amp\wattage do you drive them with? Do they play loud?
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