Phase plugs

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Just wanted to add my tuppence worth on the subject. I installed a pair of Dave's phase plugs into my FE167Es at the beginning of last week, and I've been listening whenever I've had chance. I'll quickly stress that Dave had no idea that I was going to write this; honest opinion only guys, and I'm impressed with what I'm hearing.

First up, I'll say that installing the things was as easy as anything I've ever done in the practical side of DIY speakers. Took 30 minutes at the outside, and I was taking it carefully. Fruits of a youth misspent making model kits perhaps, but it has its benefits. Their build, fit and finish is lovely, and they do add a certain something to the appearence of the drivers when installed.

As for their subjective effect on sound; they've brought quite a few benefits to my ears. The 167 is inherently smooth as FR drivers go, but installing these things has brought some real gains to the upper and midranges. Things sound somewhat more precise, and smoother / cleaner too in the HF. A slight ring in the upper midrange has gone completely. If there's a downside, I haven't found it. And that's with the FE167E. I have more than a suspicion that they'll do all this and more for the 166, which is a much less forgiving unit with that rising response. Either way, if you've got these drivers, then you want to seriously consider getting a set of phase plugs for them. They work. Extremely well. Anone else out there running a set of drivers with them in? I'd be interested to see if our experiences match.

Cheers
Scott
 
I got a pair of PP's from Dave and installed them in my FT-1600 cabinets, which use the FE167E. I wanted to know if they made a difference and whether I wanted to offer the PP's as a "factory" option. Well, they do make a difference, and I probably will. I made a series of FR plots at various angles both before and after. But....
I'm waiting for one of my customers to report back on his results before I write up my report.

I'll get back on this, soon I hope.

Bob
 
I'll look forward to your write-up, as ever Bob. I was wondering if you'd tried these things. A complete set of measurements as well? That sounds like it's going to be a very interesting read. I can't really do any measurements of my own (in Martin's ML TQWT) at the moment as my test equipment is a bit limited beyond ~500Hz, but I know that the drivers have never sounded anything like as good as this before. If you're planning on fitting them as a 'factory' option, I think that says it all really.

Mark -very nice indeed. Did you find that your 166s that sting at the top the standard drivers can have?

Best
Scott
 
I've got a pair that I ordered for the Beyma 8ag/n but actually didn't fit - no reply from Dave + the website still advertises the fe206 PP's to fit the Beyma's... Not a great loss as they will find their place on other drivers one day but not a good service none the less.

I'm happy about the construction + looks though, tried them on a different driver (vintage oem 12" fullrange driver) and to be honest I didn't hear any difference. I'm still a little sceptical about the phase-plug thing; many people report a smoother midrange and better highs after removing the dustcap + installing the PP's but that's exactly the result you get when simply removing the dustcap with some drivers. If you're all raving about PP's there might be something in it but my ears haven't detected it yet...

Simon
 
frugal-phile™
Joined 2001
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Klimon said:
I've got a pair that I ordered for the Beyma 8ag/n but actually didn't fit - no reply from Dave + the website still advertises the fe206 PP's to fit the Beyma's... Not a great loss as they will find their place on other drivers one day but not a good service none the less.

I did reply... i hate that SPAM make's email unreliable. I've not actually even seen the Beyma, but a client in the Netherlands did the experiment and is using 5 in his Beymas. I have a couple other clients that have gotten them for these with no complaints.

I did receive the 206/7 plugs from Alexander and found that they do fit directly. This is the case if I do the cutting of the Beyma more bravely than I did the first time. I now hold the knife at a 90 degree angle, which got rid of the inner rest ring of material. And the whizzer is still attached ! The speaker still works when linked to a sound generator so it must me allright.
Tonight I will install them in the Viech backloaded horn and let you know about the sound.
....
I think the plugs are a clear improvement, mid and high are more precise, less rough then without the plugs. I had to drag myself away from listening in order to get to work more less in time this morning.  I'll try to get you pictures and make a more elaborate report about it probabbly over the weekend. And of course now I would like to order three more plugs of this size, as I will have a Viech surround system for sacd and dvd.
Please get me the same light coloured wood again as I think that looks nice with the dark paper cone.

I do note looking at this that he had to get every last bit possible out of the way -- i had the same issue with the FE108eS.

I never got pictures of the above mentioned install.

I'm always happy to take plugs back (you'd just be out shipping -- i usually have them forwarded to somewhere close). It is also possible to sand them down to make them smaller (you will loose the black finish on yours), i do this when i have to install plugs in Coral variations of the 103A.

I will add a note to the web site saying that for the Beyma it is a tight fit.

dave
 
I use a pair of the Planet 10 Phase Plugs on my Hi-Tweek Black Box 1197's and the improvement is not slight.

I might add that, prior to the phase plug install, these speakers had been measured by Dan Wiggins of Adire at the last "Puget Sound! DIY Speaker Contest" and had a Frequency Response of plus/minus 2.5 dB from 65Hz to 15kHz. They even sounded pretty good if not played too loud. I designed them for my own use, in a very small room and had opted for extention, not SPL, so that's not too surprising.
All the esoteric mods to the driver had been done, with the exception of cone damping and phase plugs.

Later that year, I had them up at Al Wooly's Speaker Fest in Canada, where I let myself be talked into trying the Phase Plugs. OK, part of the deal was that Dave himself had to do the Mod where interested parties could watch. Two thin coats of "Puzzle-Coat" and the installation of the Plugs were done in front of many witnesses. Very straightforward and uncomplicated procedure as it turns out, and they look great. From a cosmetic standpoint it could be justified even if it made absolutely no difference in the sound.

Ok, How do they sound?
Well, it transformed a great cheap speaker into a great speaker, period! I hadn't expected much of a change, as they had sounded (and measured!) pretty good already, but I was totally taken back by the significant improvement in the midrange and the treble. I haven't had them measured since the mod, and to be quite honest, I really don't care how they measure at this point. They sound fantastic. Even my wife, who really could care less, thought they sounded "pretty good".
A couple of pictures are at:

http://av123forum.com/showthread.php?s=&threadid=10817

I need to disclose that Dave is to pay me $275,000,000.00 USD for this endorsement. He may try to wiggle out of it by pretending he doesn't remember or perhaps just an outright denial, but you read it here so you know it's true!
:smash:

Best Regards,
TerryO
 
I did reply... i hate that SPAM make's email unreliable. I've not actually even seen the Beyma, but a client in the Netherlands did the experiment and is using 5 in his Beymas. I have a couple other clients that have gotten them for these with no complaints.

Sounds fair, emails are highly unreliable sometimes. Still a weird story that my Beyma's should have a smaller voice-coil former than other Beyma's (it would surprise me if Beyma changed the design of their 8ag/n and no one knows about it)- or maybe some of the happy customers are simply mounting the PP's not on the pole-piece but on the membrane...?

Simon
 
OK. I was waiting for one of my customers to report back on his phase plug mod, but that does'nt appear to be soon. So, here's my report:

I installed a pair of Dave's PP's in my FT-1600 speakers --

An externally hosted image should be here but it was not working when we last tested it.


An externally hosted image should be here but it was not working when we last tested it.


The frequency response looks like this --

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Read the full Phase Plug Report

Bob
 
peterbrorsson said:
Cheers!
Just a thought from an amateur, how would it sound/measure without PP and dust cap?
I removed the dust caps on a pair of Vifa woofers a couple a years ago that solved the problem with some "shoutiness" and muddled midrange.
Regards Peter

Peter,
It depends on the driver in question. What works well for one driver may be the worst thing that could be done on another.

I now wish that I had Dan Wiggins measure my speakers after the phase plugs, just to have a comparison. On the Radio Shack 40-1197's it makes a definate improvement to the sound that is not subtle. I can't recommend any of the others, because I haven't heard them, but they are a quality product and are very attractive visually.

Best Regards,
TerryO
 
I will review these plugs soon....

My fe167e's in healthy BR monitors are under 100hrs & edge with shout & just to forward.. I am hoping these plugs will do the trick. I did the dust cap removal this mourning, 1st one went o.k., second one went very well. I know how to do it much better now.. Don't do it with alot of coffee in ya in the mourning!!!!!!!!! I know better, but no damage.. Now the wait...the hardest part!!!!!!!!!
 
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Joined 2001
Paid Member
peterbrorsson said:
Cheers!
Just a thought from an amateur, how would it sound/measure without PP and dust cap?
I removed the dust caps on a pair of Vifa woofers a couple a years ago that solved the problem with some "shoutiness" and muddled midrange.
Regards Peter

Removing the dust cap is usually an improvement -- it changes the cavity resonance in the coice coil above the pole piece. it usually gets better when you fill the hole left behind... in the case of a woofer, wool felt works well. In a FR the harder reflective surface of a solid helps the HF as well.

dave
 
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