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Posted by Romy the Cat on
03-02-2007
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There is nothing as funny in internet high-end audio as learning about silliness of horn people. I have a huge collection images with different horn installations, one more silly the other, but any day brings the new pearls…
Here is a guy form Brazil. He it one of the yahoo-audio-designers who believes that a speakers designer should not have any brains or ears but only shell have DSP processing that should address all problems.
Anyhow, here is his horn installation degined for him by Yamamura San.
I would leave aside his brainless “symmetrical 24 dB/octave” and many other things that this guy does… let just look at the horns: 60Hz-500Hz-15 kHz. This is a homework for you: why the decisions that were made in this installation are ridiculous? Rgs,
The Cat
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Posted by be on
03-02-2007
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Just put some whizer flaps on the back of the B515 diaphrams , a pair of mandolins in the bas horns, a pair of jew harps in the midrange throat and some old and crunchy oxidized alufoil in the treble and the whole thing would integrate by tuning the strings of the mandolin, even without the DPS.(maybe?)
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Posted by Romy the Cat on
03-03-2007
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 pe1mmk wrote: | |
Pe1mm, if you wish to ask questions then you have to educate yourself on the subject, at least slightly, in order to be able to ask intelligent questions. I do not know people on-line and therefore in order do not waste my time I always try to recognize the primitivism of an opponent on any given subset by intentions of his questions in order do not be engaged in argument with idiots. If the intentions are to learn then it is fine but if the intentions to exercise own senselessness then what kind response you expect from me? No, you are not being killed by the Cat. I just was proposing that if you are wiling to get any explanation from me then you need to demonstrate a little more then your ability to poke fun at on the subject about which you apparently have no understanding. So, it would be a good task for you: try to understand the conceptual design differences between the Yamamura approach and Macondo and when you get there you will realize that in the above post of yours you did not ask any questions but just behaved like 6 years old looking at the picture of a synchrophasotron and recognize a house of his grandmamma..
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Posted by angeloitacare-idiot on
03-03-2007
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Romy
your site is very educational for me, and shure for many people who frequent your site.
But at the same time, it really nervs to see your snobism, your percepcion that who is not
so educated, has so much knowledge like you, is a moron ( how is it boring to read all the time this word ! ) your unpoliteness, your arrogance, the way you treat people. See how much you said only in the thread above:
primitivism,idiots,senselessness,no understanding,behaved like 6 years old
does it really need to answer in this way ? ok, the guy may wrote a stupid thread, but it just seems you love to humiliate people... just a little bit nicer, romy, wont be bad for your blog, and the respect people will have for you. Than it will be more fun to be around here.
Angelo
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Posted by Romy the Cat on
03-03-2007
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| angeloitacare wrote: | your site is very educational for me, and shure for many people who frequent your site.
But at the same time, it really nervs to see your snobism, your percepcion that who is not
so educated, has so much knowledge like you, is a moron ( how is it boring to read all the time this word ! ) your unpoliteness, your arrogance, the way you treat people. See how much you said only in the thread above: primitivism,idiots,senselessness,no understanding,behaved like 6 years old does it really need to answer in this way ? ok, the guy may wrote a stupid thread, but it just seems you love to humiliate people... just a little bit nicer, romy, wont be bad for your blog, and the respect people will have for you. Than it will be more fun to be around here. |
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Angelo,
An idiot, in the given context, is the person who does not engage the issue-under-examination but tries to search a rational to discredit opponent with extraneous accusations. What the hell your desire to educate other adults with manners has to do with the subject of this thread? If you do not have anything ho express on the subject then can you juts do not post anything? Why the readers of that site and myself should read your simplistic Oprah-crap, would be juts because you are numb and deaf on the actual subjects? Generally, I do nothing else in my communication with internet-posters besides reflecting and amplifying the idiocy of a given poster (if I find it necessary). BTW, this is the reasons why I tend do not reply your posts – because I would like to keep use of the profanities down. Anyhow, this was the last post in this thread that is not directly related to the Brazilian horn. If any of you, “nervous people”, upload any other articles in this thread that would not be about the installation above then the posts will be deleted. It's it.
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Posted by Michaelz on
03-03-2007
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{let just look at the horns: 60Hz-500Hz-15 kHz}
What does this mean? THere seems to be three horns. Does the above mean one horn covers from 60Hz to 500Hz, the middle one from 500Hz to 15K and the last one from 15K to upper somewhere. If this is the case, I don't know what to say. I wish horns could do that. But it has to be that the horns function for certain parts of the freqency range, but there are large holes where the horns do nothing and the guy must reinforce the direction radiation through EQ.
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Posted by Wojtek on
03-03-2007
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I would turn upside-down mid bass horns ,mount drivers in Heavy box and cover plastic (ABS ?) horns with very thick layer of stynthetic plaster (the one LeCleach is using to "cast " his horns .So now he'd have horizontal J shape and it would be fairly easy to time align the drivers and it would look cool too. Mid -range horn seems very small for 500Hz cross I bet it is its cutoff frequency -not good .Either add another channel with bigger mid horn or move up the crossover to 800-1K . I think in that case TAD driver (is it TAD ?) would go to 15k .Time align ribbon (??) tweeter or change to horn tweter with matching efficiency for simplicity .I don't think there is much Bass below 80Hz so some bass solution would be due. After that I don't think it would be worse than 99% horn instalation out there ,do you??
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Posted by pe1mmk on
03-03-2007
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Well Cat you can call me whatever you like, but you still did not answer my question.
Both have a horn for highs, for mids and for lows, only the sub lows are handled differently.
Now who is the moron hereMe or that naughty Cat?
regards,
PE1MMK
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Posted by RonyWeissman on
03-03-2007
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What is sitting on floor inside of left bass radaitor? Looks like two bullet tweeters? I assume he is just putting them there for storage as there is nothing inside right channel.
He must be getting a lot of sound out of the back of those woofers right into his listening field. And the throats of the black things seem to have been designed for the easiset fit with the woofers, but with no thought to cut-off frequencies.
I assume he is 'correcing" time alignment prblems with digital, as you mentioned.
Bet those shiny brass horns ring like hell.
I have never build a pair of horns, though I badly need a few pairs so I am looking forward to your discussions on these monsters.
thanks
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Posted by Merlin on
03-03-2007
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There are many ways to skin a cat - none of which get close to being right. The only moronic thing I can see is to criticise a solution that has not been heard and is not intended for your ears.
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Posted by Paul S on
03-03-2007
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Based on my own long-gone experience it appears that every horn is "loaded" to sound just like a horn, in terms of length and flair versus frequency demands, not to mention phasing/cancellation problems that I would like to see/hear corrected digitally, or through any other electronic means, for that matter. Hard to say what the "bass" horn is made of, but I strongly suspect this would be a study case for your "oops" thread.
There is a reason that the best bells are made of bronze.
I would never again use a little horn like that for "HF" (my teeth...).
I understand that compression driver/horns CAN do the SPL thing like no other driver. And maybe that is why this person has gone as far as he has with his installation. Other than that, I am not sure why this is here. I never succeeded with horns but I did learn enough to know in advance that this set-up would not work for me in term of pitch, timbre and integration, not to mention the "jack hammer" effect.
Romy, I would like to know in specific language what you think about this, since I am obviously now well behind the curve on horn installations.
Best regards,
Paul S
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Posted by jessie.dazzle on
03-03-2007
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Ok... Assuming the lack of time alignment is compensated for via a DSP:
There are likely large chunks of the frequency spectrum that go un addressed, and equally large chunks that are mall-addressed.
I would say that there are two main ranges where this system does nothing; one on either side of Mid-Range output... Meaning one in the Lower-Mid/Upper-Bass region (in other words, the range where the human ear really digs in)... And another between the Mid-Range and the HF driver. Also, that Mid-Range driver (which looks like it might be better down lower) mated to a 500Hz horn seems questionable. Running it that wide seems like wishful thinking. Also, the horn plus the adapter look too long for 500Hz (but ok, this depends on curve type).
The most obvious problem is with the Bass drivers, which are left to radiate both to the front (via the horns) as well as to the rear... which in this case really means to the front!... The rear of the drivers are aimed upward at a 45° angle where the sound would bounce off the ceiling, then continue at 45° right down to the listening point, arriving I would guess somewhat late to the party. This is not something that can be fixed with a DSP (the output from the rear of the cone being physically linked to what comes off the front of the cone).
The Bass horns look to be constructed of rubber, or perhaps ABS (plastic)... in any case, not the first choice for rigidity (other possibilty : this user is more advanced than Romy, and has discovered a means of extracting the desirable "Oops Resonances" from a horn!).
So to summarize : Output is likely to be limited to very specific ranges. Forget about Lower Bass. There is likely a semblance of Upper-Mid bass (albeit out-of-focus). The real question is what comes out the mouth of that MF horn when loaded with that driver. As for HF, I would guess it is all alone, highlighting the void below it.
All in all, perfect for playing that copy of "Café Blue" sitting on the floor.
What I see right with this picture : I like the idea of using thick cast metal for the smaller horns... in this case the Mid horns... If only they would have been left with a rough sand-cast surface. Also, though he may be ignorant, you have to admit the guy is at least trying.
jd*
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Posted by Romy the Cat on
03-03-2007
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| pe1mmk wrote: | Well Cat you can call me whatever you like, but you still did not answer my question.
Both have a horn for highs, for mids and for lows, only the sub lows are handled differently. |
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I do not think I called you with names. Names are just symbols - expressing certain thinking some people insistingly suggest associating them with the emblematic names. If the “horn for highs, for mids and for lows…” was only the things that you have seen then good luck for you - the level of Audio Asylum or the Tannoy Group is the perfect place where you will find collaborators of your magnitude. BTW, are you the guy who runs that Tannoy Group?
| Wojtek wrote: | | Mid -range horn seems very small for 500Hz cross I bet it is its cutoff frequency -not good |
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Well, the guy said that he uses symmetrical 24 dB/octave everywhere – so it enough to run away doe the tape rate of the MF horn but to use 24dB? And partially in the horns? I think it is better drive the system from the output of a cellular phone…
| Merlin wrote: | | There are many ways to skin a cat - none of which get close to being right. The only moronic thing I can see is to criticise a solution that has not been heard and is not intended for your ears. |
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It is incorrect Merlin. It is summit of stupidity to look at the pictures and without understanding what is going on to criticize. However, the people who are familiar with the subject see no only the colorful pixels but intentions, means and topological accomplishments with witch they dealt with and have reference points.
| RonyWeissman wrote: | | He must be getting a lot of sound out of the back of those woofers right into his listening field. |
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No kidding! How dare you make such a Moronic statements if you never heard and is not intended for your ears!!! :-)
| jessie.dazzle wrote: | | Ok... Assuming the lack of time alignment is compensated for via a DSP:
There are likely large chunks of the frequency spectrum that go un addressed, and equally large chunks that are mall-addressed.
I would say that there are two main ranges where this system does nothing; one on either side of Mid-Range output... Meaning one in the Lower-Mid/Upper-Bass region (in other words, the range where the human ear really digs in)... And another between the Mid-Range and the HF driver. Also, that Mid-Range driver (which looks like it might be better down lower) mated to a 500Hz horn seems questionable. Running it that wide seems like wishful thinking. Also, the horn plus the adapter look too long for 500Hz (but ok, this depends on curve type).
The most obvious problem is with the Bass drivers, which are left to radiate both to the front (via the horns) as well as to the rear... which in this case really means to the front!... The rear of the drivers are aimed upward at a 45° angle where the sound would bounce off the ceiling, then continue at 45° right down to the listening point, arriving I would guess somewhat late to the party. This is not something that can be fixed with a DSP (the output from the rear of the cone being physically linked to what comes off the front of the cone).
The Bass horns look to be constructed of rubber, or perhaps ABS (plastic)... in any case, not the first choice for rigidity (other possibilty : this user is more advanced than Romy, and has discovered a means of extracting the desirable "Oops Resonances" from a horn!).
So to summarize : Output is likely to be limited to very specific ranges. Forget about Lower Bass. There is likely a semblance of Upper-Mid bass (albeit out-of-focus). The real question is what comes out the mouth of that MF horn when loaded with that driver. As for HF, I would guess it is all alone, highlighting the void below it.
All in all, perfect for playing that copy of "Café Blue" sitting on the floor.
What I see right with this picture : I like the idea of using thick cast metal for the smaller horns... in this case the Mid horns... If only they would have been left with a rough sand-cast surface. Also, though he may be ignorant, you have to admit the guy is at least trying. |
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Sure, Jessie. You are right and you even spotted the “Patriarchia” Barber that made me to smile too. Too keep for this horn (it is aluminum-made) without back chamber is so funny that … it become even not funny. The only way to make 60Hz horn so short is open up the throat to full throttle, most likely the full 15” as the size of that 515G driver. If this guy has such a large throat then this horn has very little gain. Let presume that it does +3dB at its lover at its lover knee. Then, (with the back chamber wide opened and positioned where it is) the guy has upperbass MF arrays of two sources, with 3dB between them, reserved polarity and with time discrepancy that could not be addressed at digital domain. Do you want know how it sound? You can easy imitate it with two simple monitors. I would not even go into his MF hors – to spend so many efforts on THAT MF horns!!!!
Anyhow, the guy who own the system it looks like did not design it but recruited a Japanese guy to do it for him (whoever the Yamamura San is). I wish he sue his own brain and ears. Well, but who knows… looking at that "Café Blue" record it is very much might be the case that the drapes match the carper… :-) Rgs,
Romy the caT
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Posted by Merlin on
03-03-2007
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| Romy the Cat wrote: | |
 RonyWeissman wrote: |
| He must be getting a lot of sound out of the back of those woofers right into his listening field. | |
No kidding! How dare you make such a Moronic statements if you never heard and is not intended for your ears!!! :-) Rgs,
Romy the caT |
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It is not moronic to state facts - it is however moronic to jump to subjective conclusions without sufficient data. Whilst we can all see objective failings in any design, surely we are adult enough to accept that it is the subjective impression that counts, and it is impossible to form a vaild opinion from a photograph.
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Posted by jessie.dazzle on
03-03-2007
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I see some posts predicting that the use of bronze for the Mid-Range horns (see photos above) would result in ringing... Well, I respectfully beg to differ; I think this is one area where the designer may have done well... Too bad he polished them.
While not a horn expert, I do have a lot of experience working with metals.
It is not correct to assume that because bells are made of bronze, anything made of bronze will ring.
All materials have a sonic character, which reveals itself differently according to the form the material is given (yes I know the form of these horns approximate that of a bell, but read on), and of course the nature of the forces to which it is subjected.
"Ringability" resulting from a sharp blow (as is the case with bells) is one thing... The ultimate in that sort of "ringability" can be found by lightly tapping a wrench on a high-quality forged steel anvil sitting on concrete; a good one will rival a musician's triangle. The grain imparted to steel by the forging process reinforces propagation of the resonance. (Remember this next time you shop for a vice... or a Katana).
To get good ringing, you need stiffness. Steel, glass, the wood used in xylophones ; it will all ring if the conditions are correct when the material is struck.
Does this mean we should make our horns from chewing gum?
No. The kind of ringing we might encounter with horns is not the result of sharp impact ; It is a resonance born of sound pressure.
You can yell at the anvil or the triangle all day long, and neither will resonate with your voice. However, yell loudly enough at a big gong and it will resonate audibly.
Resonance is directly related to mass for a given area, or in the case of a horn or bell, a "Radius-to-Wall Thickness Ratio". This resonance is driven upwards (in frequency) by the addition of mass to a given surface area... (this is why you don't see anvils hanging in bell towers). Resonances in a horn can be effectively negated by mass (in theory, driven up out of the audible range).
More area with less mass = More resonance, so the material is allowed to express itself in combination with the form, and deliver whatever accent the combination might yield. (A brass trumpet or a bronze French horn are good examples...BTW, the only place they are called "French" horns is in the US and some times in the UK... The remainder of the world simply calls them... "horns").
Less area with more mass = Less resonance (higher frequency really), so the material is not "allowed to express itself", and the form is nothing more than a series of reference points which conspire to shape the results. (A lead, gold, or bronze ingot is a good example).
The MF horns in the photo appear massive for their internal area, and therefore have a ratio more akin to an anvil than a bell. And like the anvil, you could yell at them all day, and they would not resonate with your voice. But unlike the anvil, due to the structure of bronze and the mass involved here, tapping them with a wrench would likely result in... a tapping sound. Make them from forged steel, tap them, and they would ring nicely. For audio, at this sort area to mass ratio, they could be made of just about anything... Surface finish would probably have more influence. I have been conducting some experiments (excrements I mean) with Upper MF horns which confirm this.
The mass to area ratio of the anvil means the pitch is high. I would like to hear a church bell that would still have the form of the bell (to achieve a lower, directional pitch), but be made from forged steel!
By the way : Bronze became the preferred material for construction of bells because it can be cast thinly and still resist shock (as compared to iron for example, which is brittle and involves more difficult-to-maintain casting conditions; mainly temperature), and of course bronze does not oxidize.
jd*
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Posted by Romy the Cat on
03-03-2007
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Jessie, actually I do not think you have seen me complaining about his chose of material (the only problem is the he need to fonish it other the metal). I know little about metals but I am sure that that the thing has a mass, in regard to 500Hz, that makes the chose of material irrelevant. It obviously was very difficult and expensive to make this MF from bronze or whatever it was and all that I said was: “to spend so many efforts on THAT MF horns”. This horn is similar to the Vitavox “narrow” S2 horn (the one that was use in some CN191) and the imaging problems from that type of horns horn are well know to many people who use them (or similar horns). I presume that it was over $1000 or raw materials in those rectangular horns, not to mention the labor… I have no idea way people went in such huge expenses and did doe not go for a convention radial horn…
To the rest subscribers of the thread, I deleted 5 posts where you kind had fun defeating your egos and did not comply with the subject of this thread not with the subject of this site: “Advanced audio and evolved music reproduction techniques”. Please do not do it again, it does not serve any purpose and if you will not seas as you will meet the face of the quite mean Pussy. Rgs,
Romy the Cat
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Posted by Merlin on
03-03-2007
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One thing that is unclear is the mid/HF crossover. Is there more information?
Is the system triamped with S15's or biamped with 2 x S30 and S15? You say the crossover is at 15khz yet the UT-045be has a built in switchable passive crossover which would most likely be set at 16khz. That makes the system sensitivity a poor 98dw/w maximum which makes you wonder why he bothered with the bass horn. You need to provide more in depth information.
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Posted by Romy the Cat on
03-03-2007
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Merlin, I wonder why you need more information if according to you: “the solution that has not been heard and is not intended for your ears”. You migration from sightless denial to desire of self-education is very… I would say fast but still admirable. Anyhow, I would attribute that older post of yours to the syndrome of intermediate audio-hypochondria and I’m glad that you went over it.
Well, here is the text how the owner of the system describes it:
" Pair of full-range horns and their peripheral electronics. Side-view of left aluminum upper-bass horn + mid-range horn and the small very-high-frequency JBL UT-045Be quietly 'sitting' over an acrylic board. The single Revel unit covers from below 20 to 60Hz. Upper-bass horn from 60 to 500Hz; mid-range horn covers from 500Hz to 15kHz; the super tweeter from 15kHz to inaudibility. Slopes are symetrical and 24 dB/octave. Close-view of the side of the mid-range bronze horn and the incredible UT-045Be unit. Valve electronics by Eduardo Lima (AUDIOPAX). At left the Master Loudspeaker Designer Bé Yamamura whom I had the opportunity and honor to visit in London, England, in a distant day of November, 1981.
The sound ? Well ... the sound is natural, very linear but not sterile. There is an unlimited sense of power and freedom from the deepest bass notes to the extreme highs. The image (vertical and horizontal directions) is as precise as like any other studio monitor ... but the sense of power and majesty with large orchestral and choral works ... is unbelievable !!
Two particular frequencies [one near the cut-off of the upper-bass horn and other, also near the cut-off of the mid-frequency horn] were audibles using piano and (whispering) female voices. Both were 'terminated' using very deep notch filters with a Q of 30 !!
Large horn systems need really large floor spaces and they also have a 'tendency' to work better at unconfortable high SPL levels. Good for audio demonstrations but not for the everyday use. It was very, very difficult and much time was consumed to 'solve' the problem of the fusion of the particular sound signatures of the Revel and of the upper-bass horn. This not only was finally 'solved' but now there aren't any detectable sound signatures coming from both operating ranges and this from whispering 40 to thunderous 105 dB(A) SPL levels !!! Really not bad !!! This 'magic' was only possible after some specific program routines writen for the state-of-the-art SymNet DSP. Multi-amplification plus the use of DSPs (or as they call them 'Loudspeaker Management Units') is the way to go with any loudspeaker system including Tannoys. Expensive ... maybe, but use them once in your life and you'll never --n-e-v-e-r-- look back !"
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Posted by Paul S on
03-04-2007
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Thank you for the lesson in metalurgy, Jessie (seriously). Actually I have no reason to believe that the bronze horn in question rings "like a bell" "when struck" in the same way a real bell rings when struck, so that does seem to put my remark off center. But I have heard a good deal of "ringing" coming from [polished] metal horns like this one due to internal resonances generated, reflected and amplified by the horns themselves. I always return to the Altec horns because that's where I left off. The stockers "rang", alright, and we wound up getting the best results making ours from tar or lead. Bronze was and still is too expensive for my experiments, but I would still have to hear this one to believe it does not produce any ringing, configured as it is, even though I accept that the horn itself is not vibrating like a bell does when struck.
The subject of horn finishes came up a while back in another thread , and it might also be relevant here with respect to the bronze horn, which, as you say, should be well-damped due to its mass alone. I've heard matte aluminum and pot metal horns make very audible contributions, but we found that shellac "dope" could damp this some, certainly more so than just the mass of the shellac would suggest, or at least the mass of the shallac as compared to the mass of the horn itself. And is the case of the "doped" horn not somewhat different from the doped [paper] driver, even if the goal in both cases is to shift/control resonance?
Best regards,
Paul S
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Posted by Romy the Cat on
03-04-2007
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Actually if that horn would not be bending atop, go for another couple feet vertically, consequentially has a smaller throat and of course has a strong back chamber then it would be a very good J-horn (presumably that the walls and joints are not resonating)
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Posted by Wojtek on
03-04-2007
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| Romy the Cat wrote: | | Actually if that horn would not be bending atop, go for another couple feet vertically, consequentially has a smaller throat and of course has a strong back chamber then it would be a very good J-horn (presumably that the walls and joints are not resonating) |
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Then if positioned upside-down with strong triangular back chamber could make a solid stable base for the rest of horns ,also time aligment would be less problematic . I wonder what would be optimal crossover point assuming there is no change in the system and if passsive 6dB filtering would be possible. I have to admit that I did not read trough your metal casting posts ,but from my casting experience (bronze and aluminum ) casts are porous and if tick enough non resonant at all. Good tread ,it reminded me that I have an acces to foundry.
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Posted by jessie.dazzle on
03-04-2007
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Paul,
After looking at some photos of Stock Altec horns, though they appear reasonably stout, I can believe they would still resonate when excited by sound pressure alone, as they are still on the thin side if left as bare metal.
See them here :
http://www.lansingheritage.org/images/altec/catalogs/1978-pro/page12.jpg
I would guess these horns (the cast ones) are aluminum : Aluminum and softer metals will have a duller ring, but they will still ring if the proportion/ratio favors audible resonating.
As you suggest, these horns could be damped by putting their surface in contact with a gelatinous coating... Achieving the same effect as when you hold a musicians triangle by your fingers and not by the string.
What is really happening here is sort of the opposite of pushing the resonance up in frequency (as is the case when adding more of a stiff material)... Instead, the resonating energy is immediately converted to a tiny amount of heat energy via your malleable finger tips.
I recently discovered an excellent damping material. The French are absolutely robotic about roll-up security window coverings... Which are vigorously retracted at the crack of dawn up into metal cylinders, which resonate like hell... There is a Spanish company that offers a solution in the form of a semi-cured, gooey rubber sheet with an adhesive backing on one side ; it is intended to be stuck to the insides of the cylinders... This stuff is a bit more than 1/4" thick, and heavy as hell (I carried a roll of 2 square meters home on the subway... exactly like transporting an entire cow in the form of freshly ground beef... pure dead weight. I am certain it would immediately silence even the most ringy horn (or bell). This would be more cost effective than making a horn from a mass of solid metal substantial enough to achieve the same effect.
Along these same lines, some of the large multi-cell horns from Vitavox/Philips were hallow fabrications designed to be filled with a damping material... Usually either sand, or mix of wax and tar.
As for doping/damping speaker membranes... In that case you are not only converting the tiny resonances of the speaker membrane to heat, but you are also adding considerable mass to the moving assembly.... Thats all mass that must be accelerated, stopped, and accelerated again... Think of an internal combustion piston engine ; good ones have light-weight reciprocating parts so they don't rip themselves to pieces at higher piston speeds (titanium connecting rods, light-weight pistons, etc). Back to speakers : From a pure physics point of view, the lightest, stiffest moving mass possible should be the goal. However, it is not so clear cut as this ; Paper for example can be beat for stiffness/lightness, but it would seem only at the expense of tone. In the case of a well conceived driver, I can't see that doping would result in anything other than an attenuation of detail. If it seems to result in an improvement, I would be suspicious of the design of the driver.
jd*
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Posted by Paul S on
03-04-2007
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FWIW, I've done the cone doping myself, and my first reaction to doping paper cones is suspicion. Why does it "need" this, and how/why will it really "help"? But I injected this example only to set it apart from the [Altec] horn doping, relative mass versus X, as I think this still relates to the idea/questions that initiated this thread.
What still remains unclear to me is how to predict/control what I hear as a more-or-less "self-induced" "ringing" in horns that appear to my eyes alike to the bronze example in the picture. I have also seen/heard chrome-plated horns similar to the bronze example, and they were terrifying. I don't "see" this in Romy's wide-throated, stumpy, band-limited wooden horns because these are pretty new to me and so do not "ring my bell", as it were, and they also "make sense" to me based on my own experience. Why do I "see" that the bronze horn will "ring", and/or what am I missing with respect to curves vs. FR vs. throat vs. length in this case that somehow makes this particular bronze "wide-range" horn free of the ringing my experience "tells" me I would hear? I don't expect a primer in horn design, just assurances that I'm off base would be fine, and I'll do my own homework from there.
Best regards,
Paul S
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Posted by jessie.dazzle on
03-05-2007
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Paul,
Well it would be silly for me to insist that I'm absolutely correct here, as I too am only basing my analysis only on what I see, and what experience I have been able to amass (some profession-related, a little in horn making, and quite a bit in casting bronze sculptures).
Looking closely at the photos, I would estimate the thinnest part of the Brazilian MF horns to be about 5/8 of an inch thick (at the mouth). By comparison, all Altec MF horns I have been able to find in photos appear to be no more than 3/16 inch thick; what's more, the thickness appears to be fairly constant all the way back to the small end. By contrast, look at the massive block around and under the throat of the Brazilian horns.
Never the less, as unlikely as it would seem to me, it is not impossible that your prediction turns out to be correct...
Because despite what I see as a significant difference in surface to mass ratio, I could be over looking something else which would still cause the Brazilian horns to ring, and which could have been equally present in your Altec horns, and caused them to ring.
Only one sure way to find out...
With regard to "horn doping"... that is an interesting way of seeing it. I've been making horns from steel and natrual fiber-reinforced, hard modeling plaster... they are very heavy and thick enough that they do not ring or resonate, so there is no need to add anything to the outside. I am however currently experimenting with different resins, in which to suspend various small particles, creating a textured and somewhat supple layer on the inside... The horns already sound good in bare plaster, but I want to know what effect various treatments to the inside might have.
By the way... While not wanting to suggest you replicate these Brazilian masterpieces, I can confrim that you've got the perfect amps to dip your toes back into horns....
jd*
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