| Midranges, midranges, midranges - Click HERE for Original Thread |
| lovitz |
| I'm working on a design that includes the XT25 and the Morel HU9.1. I'd like to use the Vifa D75 midrange, but some other posts on here seem to cast a negative vibe about the D75. I'd like to use it because it's sensitivity is close to the XT25, but SQ wise, is it a good choice? |
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| v-bro |
I have two of them and they really sound like sh**, just any cone midrange would be much preferred....
Every singer suddenly sounds like having a cold with these things...:rolleyes:
I have read about very good alternatives here on the forum (HiVi?) |
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| lovitz |
" Every singer suddenly sounds like having a cold with these things... "
Ouch.
That's enough info to start looking at a different options
Thanks |
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| tinitus |
| Your Morel woofer is 89db, so you actually need a midrange with less sensitivity, unless you plan to use double woofers |
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| Hezz |
I would generally avoid a dome midrange for a three way system. These kinds of midrange drivers have their uses. They usually work best in a four way system where you need a crossover point somewhat lower than a tweeter can go with a first order filter. It is best to think of them as a low ranging tweeter. It might work OK if you have a crossover frequency to the woofer at around 700 Hz or higher. But this puts the filter right in the fundamentals and is best avoided as it required a very good and tweaked first order crossover not to mess up the fundamental tones.
The tonal quality of the sound in the lower fundamental frequncies of these units are poor. Better to use a 4 or 5 inch driver if you need small. The flange of the D75 is as big as a 4 inch or 5 inch cone driver anyway. |
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| lovitz |
| Thanks for the input guys! |
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| grantnsw |
Hi Lovitz,
Just my beginner '2 cents' worth. I have an older version of the D75's - I never liked them - they never sounded good.
So after much deliberation and extremely useful advice from Sreten in this forum, I've decided to upgrade to the Seas MCA15RCY midrange, when I can afford them. Price is pretty good though ~$90 Au,
I'm just short of cash! SPL quoted at Seas is 89.5dB, so they might be a good match? The response looks great too. I hope this helps you. best wishes for your project, grant |
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| lovitz |
| well I was browsing the Zaphaudio site and he seemed to no like the Morel, both tweeters and woofers....so I don't know if I'll have to reconsider those....blah....too many options! |
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| Dag |
| The Peerless HDS 4" PPB(830870) or Nomex(830872) would be a very good mid for the XT25. |
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| lovitz |
I'm actually strongly considering switching the woofer to Peerless E205 and the E106 for midrange.
After reading Zaph's results on the Morel HU series, I was less than impressed with going that route.
Another question, with a cone midrange, is it wise to put it in a sealed chamber? or vent it?
Thanks again Guys. |
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| Dag |
| quote: | Originally posted by lovitz
I'm actually strongly considering switching the woofer to Peerless E205 and the E106 for midrange.
After reading Zaph's results on the Morel HU series, I was less than impressed with going that route.
Another question, with a cone midrange, is it wise to put it in a sealed chamber? or vent it?
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E205 & E106 are excellent speakers but remember that the sensetivity is only 84dB for E106. Nomex and PPB 4" has 87dB sensitivity.
I would put the mid in a closed box.
D |
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| lovitz |
| ohh that's right I forgot about the 84db sens..... I think I had the 5 1/4 plugged into xover pro... |
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| amp-guy |
I have two pairs of the Vifa D75 that have kicked around here for years , and would have to agree the are dull lifeless
and boring. Icant beleve they still make em.
I am using some JBL 104H2 5" cones now that I actually like.
However the are hard to find. |
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| v-bro |
Large domes never thrilled me actually, still have to stumble upon a good sounding one... cone midranges perform a lot better is my experience...
But the D75 really can be replaced by a clock-radio speaker...:D
I thought they quit this midrange a long time ago....
Many people expect those shiny things to perform really good because they look quite capable (at least I did in the past), don't be fooled by this! :no: |
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| lovitz |
| quote: | | Large domes never thrilled me actually, still have to stumble upon a good sounding one... cone midranges perform a lot better is my experience... |
That's interesting. Have you heard the ATC Dome Midrange? |
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| v-bro |
Yes I did, that one's pretty good (SM75). I also liked Dynaudio pretty much....
But I have ESL now....(ESL-57...pretty hard to improve if y'ask me...) |
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| lovitz |
| so just a final yay or nay....Peerless E152 will cross high enough for the XT25? |
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| lovitz |
| yes that's the one. |
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| v-bro |
It's a nice driver, but seems to have pretty fierce on-axis response above 2Khz. So it will probably need extensive filtering to use it for frequencies above 2Khz. With a low order filter you probably can't go even much near 2Khz. This might make it harder to implement, but nevertheless worthwile...I think, because other features seem to match the other drivers quite well.
But I haven't worked with this specific driver yet...I only speak of what I expect from it reading the datasheet...
On the other hand there are many drivers with 'warmer' (cone breaking-up at a lower freq.) response that will make the implementation more easy. The Peerless belongs to a newer generation of drivers with stiffer and lighter (less internal damping) cone material and therefore higher octave peaks occur, the light rigid cones are said to give 'faster response'.
Read this article with profound argumentation on the subject, but written by someone who doesn't 'believe' in 'fast' sound:
http://www.soundstage.com/maxdb/maxdb061999.htm |
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| lovitz |
Thanks again for all the information.
I'm going to cross it with the XT25 @ 2K with a 4th order APC. I was thinking about crossing it at 2.5K but I think that's asking a little too much for the 5 1/4 mid. |
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| v-bro |
| I think 2k demands more from the tweet than 2.5K from the mid..... |
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| lovitz |
True, but I've heard that 2K shouldn't be a problem with a 4th order filter.
Hell, Blue Sky crosses over their design at 1.8K, not that I agree with that, but I've heard their systems and enjoy the sound. |
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| cotdt |
| Why XT25? It needs a high crossover point. The XT19 sounds a lot better, and only needs a slightly higher crossover point, like 2.5kHz. In commercial designs the XT19 has even been crossed at 1.8kHz. Seriously though, the XT19 sounds a lot better than the XT25, and is much cheaper. |
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| lovitz |
well I looked into the XT19 as per your suggestion and found a good point. Apparently the XT19 as a better off-axis sound than the XT25, due to it's size.
Most 1" tweeters don't perform that great off axis apparently.
I modeled a crossover in XOver Pro and I think It'll do ok at 2.5K.
XT19 it is.
Thanks again guys. |
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| v-bro |
Indeed that XT19 looks better...I have 19mm tweeters in two speaker systems and noticed the highs are better spread on those than all the 25mm domes I have...(Mission 762 and small BNS bookshelves with SEAS 19mm tweeters, compared to Morel MDT43 and Monacor DT-25S and Vifa HT-275D2 and so on.....)
Though the resonance frequency is much lower on all the 25mm models...
Here's another thread with a discussion about the choice between the two:
http://www.iascamalaysia.com/forum/...read.php?t=5645
Note that one person advises not to use the XT19 under 3K!
I'm not a fan of low frequencies from domes myself, I much prefer a cone driver to go as high as possible....than perhaps a supertweeter.... |
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| cotdt |
Yeah, for car audio you should cross the XT19 above 3kHz since you'll be playing them insanely loud. Remember car audio competitions are often judged based on SPL. 150+ dB will melt your ears! I've been to these competitions so I know.
But for home audio 2.5kHz is just fine, and the XT25 needs about the same high crossover point, anyway, maybe only slightly lower. Besides, the XT19 is far cheaper at only $13 each. |
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| pjpoes |
| quote: | Originally posted by cotdt
Yeah, for car audio you should cross the XT19 above 3kHz since you'll be playing them insanely loud. Remember car audio competitions are often judged based on SPL. 150+ dB will melt your ears! I've been to these competitions so I know.
But for home audio 2.5kHz is just fine, and the XT25 needs about the same high crossover point, anyway, maybe only slightly lower. Besides, the XT19 is far cheaper at only $13 each. |
CotDT please don't take this offensively but I think you should take some time to read more of the good posts and learn more about this stuff before posting advice. I read this and then read other posts you have made, and question if you really know what you’re talking about.
First, Car audio competitions based on SPL don't typically even have midrange or tweeters in the upper levels of competition, and at the more average level, they are insignificant. The output generally that we are most concerned with is in the 50-70hz range, around the resonant peak of the car, and thus is only coming from the subwoofers. I was a New York State USAC champion in the pro class in 1999 and 2000, and placed third at nationals in 1999. I also competed for a short while in IDBL, but didn't stick with it long enough to place.
The only type of car audio competition in which the midrange and tweeters matter is SQ competitions, in which case SPL is not important. They do have one SPL test worth some points, but overall it’s an unimportant part of the competition, and has long been argued that it should be removed. I switched over to Iasca competition in the summer of 2000, as SQ was really more my passion, and SPL was really more about who can afford the most stuff, and not real design work and quality engineering. Around the same time MECA was formed and I became a New York State regional representative and hosted events until 2002. Anyway, too my point, in order to increase SPL from the mids and tweets during competitions we would cross over much higher than 3khz. We used to use these screwy setups which changed it so that the tweets were crossed over at say 5-6khz, mids at 500hz, and the woofers run bandpass from 40hz-80hz or so. It worked for a few extra decibels, but again, this was for a very minor part of the competition. I was also one of the first people to ever break 150 decibels in this type of competition. In SPL competitions with subs they use a different weighting scale and so you see SPL's in the 150-178db range commonly. In SQ comps, they weighting scale used didn't allow this and most people measure between 110-130 decibels. My team, an extension of Kicker Competition Team through Benchmark Audio, was among the first to break the 130 decibel range, and then after installing 6-12" solobarics with 1200 watts each, 4-8" midbass drivers with 250 watts each, and 4-4" midranges with 250 watts each, 4-1" domes with 150 watts each, I was finally able to do 150.9 dbs. This is no longer a record, but the current record is only slightly higher, and I just would doubt, unless you went to major competitions, that you have ever witnessed this sort of performance. That is unless the SQ competition is not sanctioned and is using the wrong weighting scale, which I have seen many times, as most people are unaware of this. I would also add that you can only receive 140 points for the SPL portion of an SQ competition, and scoring more than 140 decibels is not needed. Nobody bothers normally; my high score was an unofficial record as it didn’t matter for anything. It just reflected that I had a really loud SQ system. It was an overkill system which only existed like this because it won shows, I hated its sound, and in 2003 I changed to a street class in which the car install was very basic, consisting of a simple 2-way setup in the front with all scan speak drivers, and a single 12” subwoofer in the rear. However that class was soon taken over by glitz and glam, and I then left car audio competitions, at least for now. I am by no means the end all on these subjects, but having competed for almost 8 years, and having been involved in the design and tuning of every system ever installed in my car, doing the installs on all the systems from 2000 on by myself, I have a bit of knowledge. The one area I know very well are the rules of competition, Because I was hosting events, I learned the rule books backwards and forwards over the course of my tenure.
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| v-bro |
Hi Lovitz,
perhaps this is something:http://www.bmm-electronics.nl/Produ...Product_ID=2729
I have two 135KEP and use them as midranges, I cross them at about 3.5K to Vifa HT-275D2 (25mm softdomes). It produces very detailed sound and both can be used up to pretty high frequencies...
Here's the 135KEP:
http://www.bmm-electronics.nl/Produ...Product_ID=2728
A nice touch is the coating on the kevlar is hard at the rear and soft at the front of the cone, this enhances internal dampening. Maybe that's why they sound so neutral... |
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| Daveis |
I've really liked the RS52 from 800-4khz with LR4. But I admit it sounded funny to me at first.
For those that want to cross over lower, maybe the Tangband W4-1337SA used as a dedicated midrange. |
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| alan-1-b |
Tymphany - owners of Vifa and Peerless brand names - have replaced the Vifa D75MX-31 with a new model :-
D75MX-41-08
Some specifications are on Madisound's web-site, but they say the Frequency Response plot for the new 41 version is not published yet, and looking on Tymphany's site I see only the Freq. Resp. plot for the older 31 model on the 41's page !
Probably an email to Tymphany may hurry them up a bit, if they learn there are interested buyers in the DIY community.
One respected UK loudspeaker manufacturer, Ruark, is using the new 41 version in a new model.
There is also the Morel MDM 55 mid-dome.
Various Forum members like the Morel MDT 33 tweeters and some others in their 30 series, thus likely better than the 20 series model tweeter that was tested by John/Zaph, thus the mid-dome could be worth invetigating. |
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| pjpoes |
You know I have very mixed feelings myself on those Dome Midranges. I mean, the ATC Dome is a really well regarded dome, and I do like its sound, though a bit unusual and disarming at first, but none the less, its own right sound. However, the Hi-Vi Dome Midrange and the Parts Express Dome Midrange I was really unhappy with in my speakers. My experience with the HiVi dome midrange is with the combo tweeter midrange unit in a center channel I bought. I first listened with the stock crossover and decided something was wrong. I then measured the drivers without crossovers, with the crossovers, and realized a lot of the sound problems were do to strange issues with the dome midrange and tweeter. I don't currently have the ability to measure distortion, but I suspect the Hivi dome midrange has high levels of distortion. In the end I made a slightly different crossover and gave it to my father in favor of a Focal based unit I made using another designers crossover designs.
As for the Parts Express unit, I purchased those for some Bedrooms speakers, of which I wanted really good off axis response. Not only did they not measure as intended, but again, they had a strange response that gave me a domed response in that area, which I could only sort of avoid with closer crossover points, and it didn't have the good dispersion I was hoping for. Again, based on sound, I have a suspicion it has high distortion, or somewhat high distortion. Currently my favorite midrange drivers is the Scan-Speak Revelator model, and after my experience in the speakers I built for my brother, I intend to use them in a personal design soon. |
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| Daveis |
| quote: | Originally posted by pjpoes
As for the Parts Express unit, I purchased those for some Bedrooms speakers, of which I wanted really good off axis response. Not only did they not measure as intended, but again, they had a strange response that gave me a domed response in that area, which I could only sort of avoid with closer crossover points, and it didn't have the good dispersion I was hoping for. |
Which PE (assuming Dayton) mid-dome are you referring to?
Dayton DC50F-8 2" Dome Midrange
Dayton RS52AN-8 2" Dome Midrange
Dayton RS90
What frequency range and crossover slope were you using? |
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| pjpoes |
The Dayton I used was the DC50F is what I used, and it performed differently that I had hoped.
According to Zaph's test data, the RS90 and RS52AN are supposed to be great performers with a really good repsonse and low distortion. Looking at the Clio Response on Parts express website shows a really flat response and better off axis measurements than what I got for the DC50. I haven't used the RS52AN and can't even find an RS90 (Is this a new driver or discontinued driver?), so I can't comment on those at all. I wouldn't mind trying an RS90 if I could find one. Only reason I even know it exists is Zaph's comments. Given the huge price difference between those and something like the Scan-Speak drivers, and the very low distortion specs, I would love to design a 3-4 way speaker using those. I built a set of speakers which were 3 ways using a normal midbass and tweeter, but adding a smaller .75" scan-speak tweeter, per recommendation from a DIY speaker site I frequent, and like that person found, I found really good off axis response by comparison to a plain 2-way, without the discontinuous sound often associated with more typical 3-ways. It makes me wonder if using a midbass, dome midrange, 1" tweeter, and then .75" tweeter could expand this, as there is some dispersion problems with the upper end of that midbass driver in its upper end. My fear is that it would destroy the continuousness of the sound, as it does seem that a midrange wasn't used in the previous design for a reason.
As I said though, I'm not bagging on dome midranges, there are some great one, but my experience with the Hi-Vi and PE DC50 wasn't very good. Both sounded funny, they made voices sound nasally, instruments sound cupped, they lacked clarity and definition, and the response was not able to be made very flat without using the midrange over a very narrow band. I mean, I think I was using the PE one from around 850hz to 2.5khz to avoid issues. The final Hi-Vi design was like 800hz to 3khz with a notch filter and RC. |
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| augerpro |
Here is a new project using that RS52: http://www.htguide.com/forum/showthread.php4?t=26574
Can be used as LCR, but there was some mention of the maybe a more conventional driver layout if used as L&R. It's still in the design phase at this point. Interesting quasi-Deulund crossover too.
Also I haven't heard any dome mids that are really all that happy below 800Hz. |
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| dlr |
| quote: | | Originally posted by pjpoes As for the Parts Express unit, I purchased those for some Bedrooms speakers, of which I wanted really good off axis response. Not only did they not measure as intended, but again, they had a strange response that gave me a domed response in that area, which I could only sort of avoid with closer crossover points, and it didn't have the good dispersion I was hoping for. Again, based on sound, I have a suspicion it has high distortion, or somewhat high distortion. Currently my favorite midrange drivers is the Scan-Speak Revelator model, and after my experience in the speakers I built for my brother, I intend to use them in a personal design soon. [/B] |
I'm assuming that when you say "domed response" that you're referring to a peaking in the response somewhere around 1.5-2K. This would not be surprising at all.
| quote: | Originally posted by pjpoes The Dayton I used was the DC50F is what I used, and it performed differently that I had hoped.
According to Zaph's test data, the RS90 and RS52AN are supposed to be great performers with a really good repsonse and low distortion. Looking at the Clio Response on Parts express website shows a really flat response and better off axis measurements than what I got for the DC50. |
I've not used the DC50F, it's likely not comparable to the RS52 in both FR and distortion. I can say that the RS52 measures very close to flat in the critical range and the peak can be suppressed fairly easily. The shaping required for the low end may be more complicated, probably due to the (good) dispersion pattern of such a small dome.
| quote: | | As I said though, I'm not bagging on dome midranges, there are some great one, but my experience with the Hi-Vi and PE DC50 wasn't very good. Both sounded funny, they made voices sound nasally, instruments sound cupped, they lacked clarity and definition, and the response was not able to be made very flat without using the midrange over a very narrow band. I mean, I think I was using the PE one from around 850hz to 2.5khz to avoid issues. The final Hi-Vi design was like 800hz to 3khz with a notch filter and RC. |
Again, I would suspect diffraction issues. Since much of what you hear is the power response, a single measurement used for design such as on-axis only may not result in optimal response due to the diffraction.
I made some tests with quite a few measurements of this driver early on. If you're interested, I have a page on it at my site:
Dave's Speaker Pages
Dave |
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| pjpoes |
Hey Dave, I have actually seen your page before, and looked at it for the discussion on diffraction. My measurements are normally done in a test enclosure similar to the one I will use it in, if possible, and a much larger one covered in felt. My hope was that an Infinite Baffle covered in thick felt might act like no baffle at all. I, like you, though to a lesser extent, like to use felt discs to change the response of my speakers, and improve peaks and nodes.
This is a different subject, but in your discussion of the midrange, you mention that because a metal dome is stiffer, it acts pistonic over a wider range. Because the tip of the dome is closer to the listener than the edge, it creates waves which arrive at the listener first. The phase device acts to block the signal at the tip, as you say. How does this work on an inverted dome like my Focal tweeters. These also use a sort of phase/dispersion plug shaped like an oval cone, with the point at the center. It seems like in the case of an inverted dome the center of the dome is farthest from the listener, and that you would want to block the edges, not the center. Did I misunderstand something you were saying? If I didn't could this be why many companies using Focal tweeters remove that device? I've wanted to, but have no extra face plates, and would hate to ruin a very expensive, and getting harder to find tweeter. |
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| dlr |
| quote: | Originally posted by pjpoes
Hey Dave, I have actually seen your page before, and looked at it for the discussion on diffraction. My measurements are normally done in a test enclosure similar to the one I will use it in, if possible, and a much larger one covered in felt. My hope was that an Infinite Baffle covered in thick felt might act like no baffle at all. I, like you, though to a lesser extent, like to use felt discs to change the response of my speakers, and improve peaks and nodes. |
A true IB (or nearly so) such as mounting drivers on a wall would require little felt. The only place would be between drivers.
But even a very large felt-treated standard baffle will have diffraction, that being the step. This is still diffraction, strictly speaking, and it can't be eliminated, only altered by the baffle dimensions and driver position.
| quote: | | This is a different subject, but in your discussion of the midrange, you mention that because a metal dome is stiffer, it acts pistonic over a wider range. Because the tip of the dome is closer to the listener than the edge, it creates waves which arrive at the listener first. The phase device acts to block the signal at the tip, as you say. How does this work on an inverted dome like my Focal tweeters. These also use a sort of phase/dispersion plug shaped like an oval cone, with the point at the center. It seems like in the case of an inverted dome the center of the dome is farthest from the listener, and that you would want to block the edges, not the center. Did I misunderstand something you were saying? If I didn't could this be why many companies using Focal tweeters remove that device? I've wanted to, but have no extra face plates, and would hate to ruin a very expensive, and getting harder to find tweeter. |
The shield on the Focal unit (I've never had one to test) is still the only way to deal with the phase issue. Dome or cone, it doesn't matter, the central area is the only place the phase issue can be handled. This is because we want the rim area output at the low range to get the necessary low end extension. You can't block it only for the upper range. I did try to do that with the RS52. It did not provide much benefit, at least any outer placement of felt. I did leave the small inner felt rope on mine, but this has more to do with a small cavity that exists underneath, not a phase issue.
Some may prefer the sound of a hard diaphragm tweeter with the phase shield removed and may refer to the resonance between the shield and dome/cone. I've not seen significant evidence that this is an issue. The upper breakup area is affected to some extent, but not significantly that I've seen. I've not compared this for perception, so I can't comment on that experience.
However, I suspect that the real change that may be perceived is due to the reduced output seen in the upper area when there is no phase shield. This affects the power response to some degree in a tapered way due to the destructive interference (phase delta) that causes a droop in the response. The shield is primarily installed to counter this droop for as much as it can. It's not perfect, but it does extend the upper end in the audible range. Remember that the off-axis response has to be evaluated as well.
I cannot make any recommendation as to whether or not you should remove the shield. I would not do so had I the experience with it because I could not guarantee that you would perceive it as an improvement. Trashing an expensive tweeter may be the result.
Dave |
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| pjpoes |
Thanks Dave, I realized after I wrote that I wasn't accuratly saying what I was trying to say. I did not mean IB, but to eliminate as much diffraction as possible. Your measurements are impressive, I can not replicate with such repeatability or accuracy. I also have a pretty poor setup using a Behringer mic, opamp based mic preamp I made, and the built in AC97 based sound card. I have simply not had the time or desire to improve things, especially with my big move going on right now.
By the way, I took a look at your three way. I'm impressed with the response, very flat, and the design looks great. I mean, to get a WAF in there it would need some finishing, veneer or paint, maybe some edge rounding, and attempts to improve the look of the felt, but from a design standpoint its top notch.
I haven't heard the tweeter you use, but I keep reading things suggesting its an amazing tweeter. I have been told I would much prefer my Focal midbass drivers with that tweeter over the TD90Tcx or 120 even. Given how much I loved the sound of the Scan Speak revelator drivers, I think I would be more likely to try something like yours before redoing my own speakers. I know there is a huge cost difference, but if I am going to put in the effort to completely build new speakers, I can't see fussing over a few hundred dollars in drivers.
As for your judicious use of felt for diffraction help, have you tried foam? I found a foam company that could cut foam to my specifications and I thought it might improve sound much like the felt, while looking a lot nicer than felt. I have tried the stuff from Parts Express, and my own measurements showed similar improvements, but I was unable to cut it nicely. Finding a way to improve sound without making an ugly speaker is tough I must say. |
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| dlr |
| quote: | | Originally posted by pjpoes Thanks Dave, I realized after I wrote that I wasn't accurately saying what I was trying to say. I did not mean IB, but to eliminate as much diffraction as possible. Your measurements are impressive, I can not replicate with such repeatability or accuracy. I also have a pretty poor setup using a Behringer mic, opamp based mic preamp I made, and the built in AC97 based sound card. I have simply not had the time or desire to improve things, especially with my big move going on right now. |
This is one of the reasons I still use LAUD for measurements, even though I have SoundEasy. It is quick and repeatable due to the lack of a calibration requirement. The sound card used has an integral mic preamp and is very close to linear. During the cross-correlation with the feedback probe there is an automatic adjustment to the standard 2.83V @1m for whatever actual signal level was used to test.
| quote: | | By the way, I took a look at your three way. I'm impressed with the response, very flat, and the design looks great. I mean, to get a WAF in there it would need some finishing, veneer or paint, maybe some edge rounding, and attempts to improve the look of the felt, but from a design standpoint its top notch. |
Thanks. Yeah, it's not very high on the WAF factor. Coincidentally, I just took it all apart to do a proper job of finishing. I may consider some aesthetic changes the don't change the basic design. I've got another system that I'm working with and can use in its place in the mean time.
The one thing that I may change is the midrange offset. The 12m is such a shallow driver that it probably isn't necessary. It actually leads the tweeter by a very small degree as it is now. This can be an advantage in that too add the small delay needed you roll off the upper end a bit more than helps to push any breakup even farther down into the stop-band. With a 2nd order crossover this is a good thing.
| quote: | | As for your judicious use of felt for diffraction help, have you tried foam? I found a foam company that could cut foam to my specifications and I thought it might improve sound much like the felt, while looking a lot nicer than felt. I have tried the stuff from Parts Express, and my own measurements showed similar improvements, but I was unable to cut it nicely. Finding a way to improve sound without making an ugly speaker is tough I must say. |
I don't know what exact qualities are required of the foam to make it a near-equivalent to felt for this purpose. The foam used for studios that can be found may require a much thicker piece for the equivalent damping. I've got a couple of samples, none that can be used on a baffle. If I could get my hands on some to test I would do so. If you have a link that you could post, I'd appreciate it.
Dave |
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| pjpoes |
| This is the foam I was talking about that I had, with a PSA backing. It is also available in 1/2" thickness. It seemed somewhat similar to the foam used on some production speakers. On ebay, there is a foam reseller who told me he could get me any type of foam I wanted, as long as I knew all the specs. Not knowing what I need, I haven't bothered, but its another option. Parts Express FOam |
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| dlr |
| quote: | Originally posted by pjpoes
This is the foam I was talking about that I had, with a PSA backing. It is also available in 1/2" thickness. It seemed somewhat similar to the foam used on some production speakers. On ebay, there is a foam reseller who told me he could get me any type of foam I wanted, as long as I knew all the specs. Not knowing what I need, I haven't bothered, but its another option. Parts Express FOam |
I wasn't thinking of it in terms of a diffraction foam, but it may be worth a look. I'm thinking of buying a sample of each of the basic foam-only versions for some testing. I'm not sure if a foam would be any more pleasing that felt, but it might be easier to work with. I have my doubts about its damping ability WRT wool felt. I have yet to find anything better.
Dave |
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| el`Ol |
| quote: | Originally posted by lovitz
That's interesting. Have you heard the ATC Dome Midrange? |
An other opinon about this unit:
Some time ago there was a Pro-Ac speaker that got a very good review in Image Hifi, a german magazine that doesn`t publish (silly) rankings like other german magazines and has the reputation to be very objective. The unusual about this review was that this speaker got a "general" recommendation for any kind of music. So I once spoke with a Linn dealer about this unit (the reason: he admitted that he had preferred the Linn electronics in combination with other speakers, not mentioning a brand). He said the ATC unit sounds a bit like ESLs, just lacking something. You can imagine I was very curious when I saw an ATC speaker at the Highend in Munich this year. My impression: Very accurate and detailed, just lacking substance. In my opinion: even more extreme than a Logan (which I didn`t like ten years ago, and again at this show). So I am not alone with my opinion and my advice would be: don`t buy without listening. An alternative to a dome midranges I would like to listen to (knowing other drivers of the brand) is the Accuton 44-8 (though not as extended as the ATC, more like other dome midranges). |
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