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In the Forum: Horn-Loaded Speakers
In the Thread: Vitavox’s S2 Survival Guide.
Post Subject: About the bug-screensPosted by Romy the Cat on: 5/6/2005

 rdrysdale wrote:
Romy, I just got a Vitavox S2 into my shop today. I notice that it has a very heavy stainless screen on the front, do you leave the screen on when using the drivers? It looks like it restricts about 50% or more of the throat exit.
Rich Drysdale

Do not let yourself to be bothered but it and with the presumed “50% or more of the throat restriction” :-) They are not so heavy screen but they are exactly as it should be for the given driver. Yes, if you blow on the screen then it would response to you with air-feedback but do not worry: this driver will have enough contrast, dynamic and brutality that you wild never search for it but rather will fight with it. Also, do not forget that the bug-screens are not just preventing the cockroaches to walk into the gap but they are the part of the driver design. The screens create an acoustic resistance in the internal channel of the driver effectively damp the diaphragm. Removing the screens will change the way in which diaphragm is damped with quite unpredictable result.

I experimented with many drivers by removing the bug-screens and ALL of them did not perform well (in MF). Some may argue that within the screen they get more transient and HF but I would reply “get better drivers and better electronics”. The S2 is as venomous as it theoretically possible WITH the bug-screens. Without the bug-screens it will act as a weapon of mass destruction. Be advised that I had in past (believe me or not) a sheet of toilet paper added to the S2’s bug-screens (metal diaphragm + nearfield is a dangers this for this driver). If you play with S2 and if you have a fully charge driver then I would give you 90% that you will end up to use it at 20-30 degree off as you would fide that S2 will be  “too much”. Removing the bug-screens will convert this driver onto a laser beam, try it, it is not difficult to do juts get ring of the 3 bolts. I personally do not thing about the bug-screens as they were the impediments to sound but rather as thy are the DIFFUSERS. I sinisterly feel that the bug-screens are very-very useful tool and should not be removed.

The only one driver that I find that the removing of the bug-screens was very beneficial was EV T350. The removing the bug-screens killed the midrange in theT350. In my case, when I use the tweeter over 10kHz it did not bother me, quite oppositely – it was very beneficial.

In the end I will bring below my old writing that I found on my file-server. I remember I wrote it to post somewhere within the Sewers somewhere in 2001 in response to the Morons’ tendency of striping the bug-screens from the Avantgarde tweeters (operating from 4.500kHz in context of default Trio). I do not know if this post survived in the archives. At that time the moderating dirt of that forum was trying to beg for itself some accommodation from some crappy manufacturers and they vandalized anything that mentioned the “competitors”.  Be advised that my initial credibly-Moronic suggestion to people to remove the screen was improperly understood… my myself. I did find during my experiments in 2000 that to remove the AG bug-screen was advantageous but at that time I was not able to interpret why it was so. Fist, I use the MF driver that went all the way to 10kHz and my AG tweeters were kicking-in then (eventually I replaced it with “inverted 808A”). Second, the AG tweeter does not have a back chamber, so they have not damped cone anyway.

Anyhow, here is comes as it was written.

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About the Avantgarde-tweeter-screens plague or a note for the archives.


“The concert of so many different birds become so disturbing that Ursula would plug her ears with beeswax so as not to loose her sense of reality” - Gabriel Garcia Marquez “One Hundred Years of Solitude”

If you look under my AA’s profile you would ask: why the hell are you still here? Well, I am not here anymore, but I still feel a certain sense of not-settled guilt (in fact I never suggested to anyone to remove the Avantgarde tweeter screens. I just admitted that I did it, which added confidence to some “waiting for the miracle to come”- type people). Now, I would like to reconcile this dilemma and probably to preserve some people from the spending time and money on the worthless and could-be costly exercise of their worst audiophileism. (Contrary to some funny “Audio industry shepherds” I have no problems to admit wrongdoing or wrongsaying.)

Below, I have compiled some of my raw thoughts regarding the topic: how can one improve the performance of the Avantgarde’s tweeters. “Improve the performance…” Do you feel that itch? If you do then buckle up and read on.

History:
For some time I experimented with the deferent cables to drive my Avantgardes. All my system are wired exclusively with the Dominus . (I sincerely consider the Dominus being a reference cable for any properly built electronics and properly assembled system). I asked myself why the connectors between the Avantgarde’s crossovers and the driver couldn’t be the same? Well, I went for this and while I was dissecting my poor Trios I discovered those “thick metal screens” on my Trios tweeters. Exploring them further, I learned that I might “painfully” remove them. I asked myself: “Are those screens between me and Music?” The virtual images of the “smelling a rose without the gas-mask” and “a beauty of the unsafe sex” popped up in my barbarian head and in 5 minutes my Trios were screenless. (The removing of the screens is not a reversible procedure).

The Conclusions:
(I will eliminate all relevant and non-relevant variables and pass the ONLY differences inflicted by the removing of the tweeter’s screens. I know what I needed to listen and I have processed the results of this research.)

Advantages:
1) I did not detect any sonic improvements or changes besides my intellectual satisfaction that “there is nothing alien on the path of the sound”.

Disadvantages:
1) Without screens the tweeters began to sound louder. I would estimate a gain somewhere around .3-.5 dB. The sound became too “hot”. Do not forget that the crossovers were designed and tested with the screens. The insertion of a sheet of “acoustically transparent” paper could resolve the problem.

2) Screenless tweeters do introduce very-very-very-very minor heights distortions. (I do not know what they are by nature.) In fact you won’t be able to hear them with most of amplifiers and cables. For the sake of research I brought 4 amps for a test and tried some alternative cables as well… this problem did not manifest itself. (BTW: 3 out of 4 of those amplifiers are considered the AA’s Mecca…) To reach the depth of the Avantgarde’s tweeters capacity you would need a killer: the single-ended Lamms. With those suckers everything was there including those “non-existing in the real world” heights. (I have to note that practically any “step down” turned on the “masking effect” and made this problem less annoying or inaudible) I made a bunch of experiments to verify that the Lamms were not the guilty party and tried all “audiophile tricks” known to me, but was not able to eradicate this problem. So, what was it? Well, you have seen the drummer’s cymbals? They have the little resonators that create that “Ketchup sound”. So, this Ketchupness was presented in the ALL high frequency sounds and slightly fluctuated with the volume. The effect to some extent reminds me of the “ornamented” sound of the HT cables within the neutral electronic components only in the very-very minor scale. I played a lot with that effect and ended up with the conclusion that it can’t be fixed unless I intentionally “dull” the system.

3) For some reason removing the tweeter’s screens apparently screwed the phases somehow (soundstage allocation). I began to have a difficulty getting my “Trio Sound”. In my room properly set, properly powered and properly “massaged” Trio horns usually “compress” air and produce what I call a “hurricane/tornado effect”. I use to be surrounded with thick and tangible clouds of compressed air that spun around intensifying space and musical time, filled with bubbles of Sound, appearing and exploding somewhere within the room, opening the sealed-within music memories and revealing Life. Since screens were removed I had only the beautiful “wide and deep soundstage”. In fact, I am still able to create my “hurricane/tornado” effect however it happens only within extremely small listening space that eliminates some desirable listening experiences. (Like exploring the Sound from the “side”, ability to “walk into the sonic event”, to “conduct” the orchestra by changing the listening position, to “torment the Sound” and so on…) I spent a long time moving everything that was movable but I failed. For some reason without the screens the heights ground down my attention to reality. I am sure the engineers would explain it more intelligently than I do.

Do I consider the removing of the tweeter’s screens as a “barbarian act”? Yes, I do, and I’m strongly discouraging the Avantgarde listeners to do so. Should the folks who have already done it be worried? I do not think so. God blessed us with the famous “masking affect” and I have some reasons to believe that you shouldn’t experience any problems.
If you aren’t happy with your Avantgarde highs then here are some notes:

1)After auditioning a number of the serious speakers ($20K and up, up, up…) I summed up (considering many other variables) that the properly driven Avantgarde’s tweeter could be considered as the reference high frequency available for the sound reproduction.

2) Under no circumstances one should use with your Avantgarde’s tweeters following height frequency vandalisms: the silver cables (they burn heights), the silver output transformers (they dehydrate heights), the push-pull amps (they impersonate the heights/mid integration), any frequency boosters (they substitute heights), ***ty DACs if you listen to the digital (do you like to feel like a dolphin?), digital correction devises (this staff combined with ***ty electronics and a horn is direct recipe to be contaminated by the sonic moronism)

3) Without going deep into the explanations and justification… here is the rule: if a listener uses a word “top end extension” to describe his/her perception of Sound then the person who designed-built-sell-suggested the amplification-cabling should be granted with the title: idiot.

4) Spend some time to play with the different amps using the stock Avantgarde speaker cables. Most of the time the Avantgarde’s tweeter will be in the order of magnitude more superior then your current or your prospective amplification. The existence of the “big tubes”, widely reputed “audiophile” name, saliva-dropping “songs” of your idiot-dealer or the sweet “help” of your inmate-amp-designer dose not automatically indicate that your amp will handle the demands of the Avantgarde’s tweeters…. The removing of those tweeter’s screens should not be the first think you have to do.

5) Under no circumstances angle the Avantgarde’s tweeter relative to the horn’s frame. It creates a huge amount of problems.

6) Avantgarde USA accumulated extensive experience with their product. I never heard them refuse to consult anybody. Prior to the violation of your Avantgarde’s tweeter virginity and removing the screens you may find it beneficial to ask them about the consequence or to read this post again.

Best regards,
Romy The Cat

PS: I won’t argue or responses to any follow-ups. The subject is all yours.

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Rgs,
Romy the Cat

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