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Hpm-Econo Redo, Aka Kpm-10.0

You've got the grille cloth, badge- the whole SheBang going on there. Looks great.
I see that changing the placement would be an issue. Have you tried bringing them out, away from the cabinet and toeing them in so that the centre of the speaker's beams intersect about a metre in front of your listening position?
Enjoy!
 
Kegger, I have built the Ewave using my HPM100's. Everything is still intact in the cabs with the waveguide on top. If I switch out the crossover components to the values you used for the woofer, what differences can I expect to hear between the original crossover and yours. Thanks.
 
Sorry guy's I've been a little out of it posting wise trying to get caught up for the fest.

I am glad to see others are doing the HPM thing with good results.. :)

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Oldski, the original HPM 100 Xover isn't much on the woofer and midrange, just a single
coil on the woof and single cap on the mid and they pretty much run wide open, woofer
xover saying 3k ish, in that config with the ewave on top they are going to run into each
really messing with the frequencies from say 1500 on up through probably 5k, it will not be
as clear and open sounding as the xover designed for Ewave and the HPM woofer, also the
Zobel circuit helps out in the bass department as well.
 
Thanks for the reply. The original x-over I was referring to is the E-wave x-over designed by Zilch. I am using it now with the hpm woofer. What I need to know is the difference in sound between it and the the x-over that you designed in the Econo-redo, Thanks.
 
OH Sorry!

Well the stock Econowave woofer xover does the opposite, cuts the HPM woofer to early
where there is a dip/hole if you will between the woofer and waveguide taking over then.

So I've modded the xover to close that gap an get rid of the hole to make a smoother sum
of the 2 drivers, the midrange performance is noticed most as an improvement, then I did a
Zobel on the woofer to flatten out the impedance of the woofer, at the same time a Zobel
also shapes that upper response of the woofers by shelving midrange on up frequencies to
"enhance" bass response by dropping everything else down a few DB. (so to speak)

I run my own DIY tube gear so Sensitivity and Impedance are important to me, plus the bit
of enhanced Bass is a welcomed bonus as well.

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The dual ports in the back serve well to so you taylor the Bass response to your liking in
tuning for different rooms/gear/preferences using the patented Zilch plugs, this feature is
going to be handy I'm sure as it looks like these will be used in my room at AKfest.....:)
 
Thanks alot for the info. I will definitely be switching to your modifications. I could tell right away that the woofer was not going high enough to meet the waveguide.
 
I built mine with Keggers crossover using all the parts he had listed and they
sound terrific. The only thing I could wish to be better is maybe have a
little more snap to the bass but the hpm's in stock form didnt have it either
so its probably not possible with that woofer.I have not tried toying with
plugging the port or anything and they sound so much better than stock
its unbelievable. I have auditioned them to some audio buddies and they
were very impressed and one of them just ordered parts to build the
standard crossover with Dayton 12" classics.
 
I got the crossover components switched in the KPM's and these speakers have really come to life.:thmbsp::thmbsp:
 
Kegger said:
So how you 2 new guy's to the KPM liking them after a bit of listening?
Click to expand...

Well after doing a little adjusting to the crossover to get them more to my liking, I am really happy with them. The problem is that my HPM's are in great condition and I cant bring myself to hack them up so for now the E-Waves are sitting on the top of them or rather the bottom because they are turned upside down.
 

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oldskl said:
Well after doing a little adjusting to the crossover to get them more to my liking, I am really happy with them. The problem is that my HPM's are in great condition and I cant bring myself to hack them up so for now the E-Waves are sitting on the top of them or rather the bottom because they are turned upside down.
Click to expand...
What, specifically, did you alter?
I have EWG sitting on top of the unmolested HPMs as you do. I originally had the woofers in some BIG cabs.
 
Spectrum77 said:
What, specifically, did you alter?
I have EWG sitting on top of the unmolested HPMs as you do. I originally had the woofers in some BIG cabs.
Click to expand...

Well you said that the 8.2uf made them sound fuller so I changed C100 to 8.7uf like yours and I agree that they do sound fuller. I also changed C2 to 6.6uf, I think that raised the crossover point a little higher on the woofer , anyways I liked it too. I don't have any test equipment so I was going off what you and Kegger had discussed earlier in the thread and experimented by ear. why did you not stay with big cabinets? I considered building some myself.
 
Hi Kegger, Mine sound superb in every way.I find myself listening to music
with more instrument sounds and vocals rather than metal stuff. They really
do shine playing jam music such as The Allman Bros,Santana,Steely Dan
and similar music.Banjo and fiddles will blow you away with the accuracy.
I listened to The Rolling Stones-Let it Bleed this weekend and was by far
the best I have ever heard it.You can just hear so deep into the music where
before the hpm's in stock form were just bright and playing all over itself and
I had to turn it up so high to get it smoothed out.I am still blown away by
the sound and wonder just how good they really are as compared to the
high end speakers of today. About 2-3 weeks of listening and they started
to sound slightly bright and I decided it was the woofer not the waveguide
so I turned the l-pad up from 11:30 to 12:30 and that balanced it back out.
Just normal break in I think. I will build another set of these for sure if I come
accross some more hpm woofers or speakers .In fact I have all the parts
to start building the standard e-wave crossovers to mate with some Dayton
10" classics and CV cabs I have.
 
oldskl said:
why did you not stay with big cabinets? I considered building some myself.
Click to expand...
They did a lot right, and we're talking about chasing small degrees of satisfaction. Soundstage and imaging were superb... and they went l-o-w. Most likely, with the aid of measurement equipment, I could answer your question accurately. Tried numerous positioning and crossover experiments, then after a few months brought the HPMs into play- "Shazaam!" Last week, tried the big cabs again, just to make sure- no go. And the HPMs have gotten me used to having that punch, too. X/Os back to Bog-Keg-standard.
 
I tried plugging the ports on my kpm's tonight and it was not an improvement.
While it tamed the bass a little,vocals went raspy and it did not sound as good. Then I tried more insulation in the cabinet by placing a pillow on the
inside behind the woofer.Once again,it went kinda raspy on me and I didnt
like it. They sound better in stock form with the factory port and factory
insulation (not much) in the original hpm cabinet.
My waveguides and crossovers are in a seperate box so just for kicks,I hooked up one of my cs 99a's to the waveguides temporarily ewaving them.
While there was improvement over the 99a's in stock form,they are not
nearly as good as the hpm's. I am sure that was not a fair comparison as
the 99a's might need an adjustment in the crossover but still,even my wife
and daughter wrinkled their noses at the 99a's and said they sounded like
they were listening to them at the back of a long hallway and I agree.Those
things always had a weird effect about them.
 
Hate to dig up a 2 year old thread, but I have been messing around with a pair of HPM-100's lately and was thinking of doing them up Kegger style. I stole all the standard Ewave stuff out of my Advents, and gave it a try with the HPM's. Even with before mentioned hole in the mids, it was an improvement over the original setup to my ears. I can only image that filling that hole will make for a damn good sounding pair of speakers.

I would be curious to hear what people who have done the KPM mod have to say about them a year or so after the fact. Are they still getting any play time, or have they been kicked to the curb?
 
HA! Long live the KPM! Just made same sized as HPM-100 cabs from MDF for the E/W HPM woofs. Woofer and waveguide closer together- no major sonic benefits that can be discerned. Will post pics if interested- nothing fancy, though.
On the Kegger-designed X/O I actually prefer the sound of CS-99A woofers (not the classic, lattice grille model, the later version with the same model number), although they have less punch. Very, very smooth.
So, yes they do come out to play occasionally. KPM's & E/W were the original inspiration that pointed the way down the upgrade road. Now running 3-ways.
 
Will post pics if interested- nothing fancy, though.
Click to expand...
Who doesn't like pic's? I would love to see some pic's.

I've considered making some new, slightly larger cab's for these, but I think I'll give it a go with the originals first. I really like those punchy HPM woofs.
 
MDF cab, same inner dimensions as HPM-100. Waveguide and woofer as close as physically possible, plenty of bracing. Stuffing yet to be tuned- just aimed to replicate the HPM damping material. Port dia and length identical to HPM.
Pic of the cab and HPM-100 woofer.

DSC_0169.jpg


Assembled cab showing Pioneer CS-99A woofer. KPM X/O on top.

DSC_0172.jpg
 
Way COOL, I like it!:thmbsp:

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As to the question of whether the speakers still get use, mine do, there is an
upgrade in the process, but it's much more expensive horns, woofers and the
compression drivers, I like the KPM 10.0's quite well and I feel they hold there
own to probably just about anything in there price range, to me they definitely
improve on the original HPM by a wide margin as well. IMHO
 
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