The Visaton WG148 fits nicely on the front of the TW034, but it needs to have the faceplate trimmed to bolt up to the WG so it can be mounted into the baffle, unless you get creative and rear mount the tweeter after the WG attaches the baffle from the front. In that case you just need to drill new mounting holes in the TW034 front flange and the WG back flange.
Most of the Seas tweeters will mount to the Visaton WG148 with just slightly slotting the mounting holes in the tweeter flange. If the tweeter has a metal grille, then the WG opening just needs a little opening up to fit.
Both are good by their intended design, but it depends on the desired cutoff point and the way the WG fits around the dome. If it doesn't, youll end up with unexpected FR issues.
Is anyone aware of a tweeter that offers a sound in between soft dome and hard dome?
Musical, yet extremely detailed?
Musical, yet extremely detailed?
A beryllium dome would be your best bet, like the T25B Bliesma.
Otherwise there are some Alu/Mg alloy (non Ti) domes that don't have such a sharp breakup,
The CTS paper cone tweeter, which is an often overlooked and underrated tweeter. I really like this one if its crossed above 2.5k.
There are also the Mundorf AMT tweeters, but they have narrow vertical dispersion.
I also like some higher end compression drivers like the Faital Pro HF108 or HF10AK on the STH100 horn.
Otherwise there are some Alu/Mg alloy (non Ti) domes that don't have such a sharp breakup,
The CTS paper cone tweeter, which is an often overlooked and underrated tweeter. I really like this one if its crossed above 2.5k.
There are also the Mundorf AMT tweeters, but they have narrow vertical dispersion.
I also like some higher end compression drivers like the Faital Pro HF108 or HF10AK on the STH100 horn.
"there are some Alu/Mg alloy (non Ti) domes"
You probably mean Seas tweeters? The new 27TAC/GB looks interesting.
Is titanium former a big deal?
You probably mean Seas tweeters? The new 27TAC/GB looks interesting.
Is titanium former a big deal?
Hey there @profiguy,
I’m fixing to mate some TWO34 to SEOS 8 waveguides (it‘ll take a little finagling) and was wondering if you could elaborate further on the quotes below?
“There's the Audax TW034 too as a larger soft dome. With some xover trickery it can play higher up and goes fairly low.”
…….. what might these tricks be exactly?
“Also, the TW034 will easily go down to 1.5k in a WG. If you're adventurous enough to drill the pole pieces and stack an extra magnet on them, you end up with a 95 dB/2.83V efficiency driver that gets very close to the Seas T35C002, but at 1/3 the cost.”
……. is your version of drilling the pole piece the same as Troels or different? And is the extra magnet (i’m assuming epoxied) in bucking or attractive alignment?
“Both are good by their intended design, but it depends on the desired cutoff point and the way the WG fits around the dome. If it doesn't, youll end up with unexpected FR issues.”
……. what exactly are the good/bad points concerning fitment? the beginning flare of the SEOS 8 will be rather close to the wide part of the dome (2mm +/-)
thanks, Bob
I’m fixing to mate some TWO34 to SEOS 8 waveguides (it‘ll take a little finagling) and was wondering if you could elaborate further on the quotes below?
“There's the Audax TW034 too as a larger soft dome. With some xover trickery it can play higher up and goes fairly low.”
…….. what might these tricks be exactly?
“Also, the TW034 will easily go down to 1.5k in a WG. If you're adventurous enough to drill the pole pieces and stack an extra magnet on them, you end up with a 95 dB/2.83V efficiency driver that gets very close to the Seas T35C002, but at 1/3 the cost.”
……. is your version of drilling the pole piece the same as Troels or different? And is the extra magnet (i’m assuming epoxied) in bucking or attractive alignment?
“Both are good by their intended design, but it depends on the desired cutoff point and the way the WG fits around the dome. If it doesn't, youll end up with unexpected FR issues.”
……. what exactly are the good/bad points concerning fitment? the beginning flare of the SEOS 8 will be rather close to the wide part of the dome (2mm +/-)
thanks, Bob
Thats a nice tweeter. It may be currently their best metal dome IMO. There were some QC issues with the first run of them, but i think they're all worked out now.
Ti former just gets you better low level resolution, better mechanical stability and less VC former resonances. Not really a deal breaker in my book if a driver doesn't have it, but from my experience it can.give the driver an edge if the rest of it is designed to be without compromise.
Aluminum is said to sound worse than any other material due to excess dampening properties, but it has advantages like being stiffer, more thermally stable and better power handling than kapton or fiberglass and maybe a fraction lighter than fiberglass.
That being said, there are many excellent HF drivers that don't have a Ti former, so its overall benefits are debatable in the real world.
@mountainman bob - To lift the top end a little you need an HF shelving filter (aka CD EQ) in addition to the HP filter. You're just tipping the upper end of the response curve a little. Its basically just a smaller cap paralleled with a resistor placed in series with the HP. You'll maybe lose 2-3 dB efficiency from it, but it can extend the HF to past 15k on the TW034. There are some on line calculators that you can use to find the appropriate component values.
I don't drill the pole piece all the way through like Troels did. It isn't necessary and just complicates things. You just need a little more volume behind the dome to lower the Qts a little, removing the less than effective synthetic foam pad and replacing it with sheeps wool. That most importantly reduces the 2k ripple that muddies up the midrange, which is the biggest issue on the TW034.
The extra magnet is added in bucking mode (repelling) to the back plate. Once the magnet gets close enough to the back plate, it will be suddenlly pulled in and stay put, but you need a thin application of super glue to make sure it won't move around.
Based on my experience, the WG throat should cover the dome surround half way and have the smallest gap possible to the WG throat. You don't want a large gap here because it causes reflections in the WG, which ruins the linearity and off axis performance. Most of the time it's easier to have the surround completely uncovered. Part of the surround does contribute to the output of the driver. It depends on the WG itself whether it will negatively affect things to cover the surround in varying degrees, but most designs totally expose the surround, as the Jantzen WG does. The fact however remains that the smallest diameter throat gets you the best HF extension.
You'll want to look up augerpro's big WG thread regarding all this. He's done a ton of R+D on adding WGs to dome tweeters.
Also, here's a design of Troels using the TW034 and Jantzen WG - JA8008 + TW034 with WG
I don't drill the pole piece all the way through like Troels did. It isn't necessary and just complicates things. You just need a little more volume behind the dome to lower the Qts a little, removing the less than effective synthetic foam pad and replacing it with sheeps wool. That most importantly reduces the 2k ripple that muddies up the midrange, which is the biggest issue on the TW034.
The extra magnet is added in bucking mode (repelling) to the back plate. Once the magnet gets close enough to the back plate, it will be suddenlly pulled in and stay put, but you need a thin application of super glue to make sure it won't move around.
Based on my experience, the WG throat should cover the dome surround half way and have the smallest gap possible to the WG throat. You don't want a large gap here because it causes reflections in the WG, which ruins the linearity and off axis performance. Most of the time it's easier to have the surround completely uncovered. Part of the surround does contribute to the output of the driver. It depends on the WG itself whether it will negatively affect things to cover the surround in varying degrees, but most designs totally expose the surround, as the Jantzen WG does. The fact however remains that the smallest diameter throat gets you the best HF extension.
You'll want to look up augerpro's big WG thread regarding all this. He's done a ton of R+D on adding WGs to dome tweeters.
Also, here's a design of Troels using the TW034 and Jantzen WG - JA8008 + TW034 with WG
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I'd like to add a counterpoint to the soft vs hard debate. I directly compared the Vifa NE19 in fabric, ano Al, and Ti one time. So all the same motor, direct A/B setup. I thought the Ti was the smoothest and best behaved of the three. The ano Al was a fairly close second. The fabric was not near as smooth, somewhat "sizzly". I did not prefer it, and was a bit surprised by that since I had somewhat believed the myths around dome material.
Another example of direct comparison of two tweeters where only the dome is different, is the original Dayton RS28. These were really popular, and used in a lot speakers that would be directly compared at get-togethers or PE's competition. Over many comparisons over a number of years, it was understood that the Al dome was the smoothest and best behaved. The fabric was more "lively" to those who like it, and more "sizzly" to those who didn't.
So it is interesting that the only two examples I know of where this dome material was directly compared, the fabric was not the smoother one. HiFiCompass's comparison of Satori tweeters was also interesting, he states "The silk dome TW29DN-B was not included in the comparison, because it is too different in sound. It was much interesting for me to compare the tweeters with rigid membranes." I don't know what that means, but it seems reading between the lines he did not find it in the same league as the rigid Textreme and Be tweeter?
Another example of direct comparison of two tweeters where only the dome is different, is the original Dayton RS28. These were really popular, and used in a lot speakers that would be directly compared at get-togethers or PE's competition. Over many comparisons over a number of years, it was understood that the Al dome was the smoothest and best behaved. The fabric was more "lively" to those who like it, and more "sizzly" to those who didn't.
So it is interesting that the only two examples I know of where this dome material was directly compared, the fabric was not the smoother one. HiFiCompass's comparison of Satori tweeters was also interesting, he states "The silk dome TW29DN-B was not included in the comparison, because it is too different in sound. It was much interesting for me to compare the tweeters with rigid membranes." I don't know what that means, but it seems reading between the lines he did not find it in the same league as the rigid Textreme and Be tweeter?
Sorry for the sidetrack @duvixan, I should have some measurements soon if this might interest you, the seos 8 horn is still available from diysg.
Thanks @profiguy, excellent info…….the circumference of waveguide opening ends up right over the peak of the surround roll and is about 1mm above said peak (see pics) that’s about as good as it could get without being in the way? Would a little putty around the inside edge of the mounting flange (without touching the surround) be helpful?
Man, those domes are dust collectors!
Thanks @profiguy, excellent info…….the circumference of waveguide opening ends up right over the peak of the surround roll and is about 1mm above said peak (see pics) that’s about as good as it could get without being in the way? Would a little putty around the inside edge of the mounting flange (without touching the surround) be helpful?
Man, those domes are dust collectors!
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@augerpro - I agree that dome material itself really isn't the main deciding factor regarding how smooth a dome tweeter will sound.
Based on my experience, a good metal dome (correctly implemented) will sound more accurate and cleaner than a soft dome and stays cleaner at higher SPLs. Most soft domes get fuzzy sounding, mainly running in breakup mode over the top end of their FR. Hard domes remain pistonic over most of their range, but the breakup mode is sharp and resonant. This is what can make a driver sound rough and fatiguing, and reducing/filtering the resonant peak mostly fixes this issue. The problem is measuring it and applying the HF notch filter correctly, as most measurment mics don't go that high to accurately measure it. You can find where the peak occurs by measuring impedance, but the magnitude can't be figured out this way. Only a decent mic can reliably measure this.
Based on my experience, a good metal dome (correctly implemented) will sound more accurate and cleaner than a soft dome and stays cleaner at higher SPLs. Most soft domes get fuzzy sounding, mainly running in breakup mode over the top end of their FR. Hard domes remain pistonic over most of their range, but the breakup mode is sharp and resonant. This is what can make a driver sound rough and fatiguing, and reducing/filtering the resonant peak mostly fixes this issue. The problem is measuring it and applying the HF notch filter correctly, as most measurment mics don't go that high to accurately measure it. You can find where the peak occurs by measuring impedance, but the magnitude can't be figured out this way. Only a decent mic can reliably measure this.
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@mountainman bob - That looks good in terms of fit. I'd probably try reducing the gap a little by sending down the throat and chamfering the inside lip of the throat so that it follows the contour of the outer half of the dome surround angle tighter without touching. Reducing this gap as much as possible will improve performance. If you get any buzzing at higher levels, some painters tape used to increase the gap will fix it.
Very curious to see your measurements with this seos WG.
Very curious to see your measurements with this seos WG.
Yah……that’s easier said than done! 😎
I picked up this pvc pipe reamer that can (with proper finesse) put a reverse chamfer on the backside of the waveguide without making the opening much bigger……..maybe a proper sized O-ring could fill the gap to the sides?
I picked up this pvc pipe reamer that can (with proper finesse) put a reverse chamfer on the backside of the waveguide without making the opening much bigger……..maybe a proper sized O-ring could fill the gap to the sides?
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I used a 3/8 drill bit to go down to the bottom and chamfered the pole piece with a chanfering bit to leave a margin of 1/4" between the chamfer and outer edge of the pole piece. The chamfer is important to the magnetic field linearity across the VC gap. Without it the THD will go up. I ruined a set of TW034s by going to big on the pole piece hole.
You'll want to read through this thread - Seas tweeter pole piece drilling
You'll want to read through this thread - Seas tweeter pole piece drilling
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I'd try the WG thr way it fits first and see if there are any weird FR anomalies. It may be just fine as is.
I wouldn't use that big reamer you have there. It will remove too much pole piece mass in the wrong area, as I explained with the magnetic field linearity change. Moat drivers with drilled poles have the pole pieces shaped the way I suggested to drill it.
I wouldn't use that big reamer you have there. It will remove too much pole piece mass in the wrong area, as I explained with the magnetic field linearity change. Moat drivers with drilled poles have the pole pieces shaped the way I suggested to drill it.
I found the notes on a single parallel notch I ran on this tweeter. The values i used were R=2.0 ohms, C=1.2 uf and L=0.03 mH. This is of course paralleled together and put in series in front of the HP filter.
The notch is centered around 25.5k. You should listen to the tweeter before and after. Its quite an interesting difference, especially on piano and cymbals. The dome will sound more natural and laid back with the filter, without any harshness. It may even sound boring before you get used to the cleaner sound after having listened to most other soft dome tweeters.
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I think you misunderstood, I mean to chamfer the backside of the waveguide with the reamer. It was in response to your statement….… “I'd probably try reducing the gap a little by sending down the throat and chamfering the inside lip of the throat so that it follows the contour of the outer half of the dome surround angle tighter without touching.”
I know it wouldn’t reduce the gap but might make the transition smoother.
I appreciated the details of drilling the pole piece though. 🙂
Yeah, sorry I misunderstood you there.
In case you are deciding on the type of tape to use in efforts to keep the VC gap clean, I've had the best luck with aluminum duct tape. I used 2 layers and nothing got into the gap. The trick is to wipe the filings with a paper towel wetted with glass cleaner in between drilling steps. Be careful not to get the pole piece too hot from drilling. The glue isn't that resistant to heat. I used parafin to lubricate the drill bit.
In case you are deciding on the type of tape to use in efforts to keep the VC gap clean, I've had the best luck with aluminum duct tape. I used 2 layers and nothing got into the gap. The trick is to wipe the filings with a paper towel wetted with glass cleaner in between drilling steps. Be careful not to get the pole piece too hot from drilling. The glue isn't that resistant to heat. I used parafin to lubricate the drill bit.