Pioneer HPM-100 successful crossover mod!

[nsxrush]

skylab,

Not at all...The bass is a bit tighter than before....but not all the way there. Need a bit help. I visited Speakercity in Burbank. They mentioned if I replace the original foam w/ the newer foam; only in the back of the speaker, it would help a little.

Lets see...mod will be completed this weekend...keep you posted.

As for using the good stuff....it was not breaking the bank...$80 total....so $300 for speakers + $80 for mod....if it replaces...$1600 IKON-6....I am far ahead of the game.

Also, I read on other sites that, HPM-100 paired w/ good tube amp..sounds better....I do not have a good SS amp to compare...but I am very pleased w/ my tube integrated.

 

[nsxrush]

Update:-
Got both X-overs modded....added the Foam on the Back of the speaker only....left rest of the original foam/fiber-glass as is.

Listened for few days now....
Instead of CD player..I used my PC-Audio to play music...so I can use Plug-ins EQ to play music. I use JRiver. I always used ASIO to play music....used WASAPI just to try for 1st time....Better than ASIO

1) The Harshness/grainy to the overall sound if gone.
2) Still Bright for my ears (I am very sensitive to that)....lowered Highs to -2.5db
3) The Bass was helped a little bit by the foam

After all of the above....very happy w/ the sound.

Hoping that the Caps and Coil after burn-in period will sound even better. Any idea on burn-in period ????

 

[nsxrush]

Another Update:-

This is for BASS.

As in the previous post, I mentioned refoaming helped a bit. But I wasn't quite happy with BASS tightness. SPECIALLY with the bass in electronic music.

Talked to SpeakerCity guys. They mentioned to try and plug the BASS PORT w/ speaker foam. Cut a round piece, just a bit larger than the port and inserted in the port.

I am very happy with this mod. Made a major difference in tightness of the bass. Now the electronic bass is very tight. If anything it may have made the bass a bit muffled (but very very slightly)....BUT I can live with this bass all day...vs the before.

 

[onwardjames]

So help me understand...

You took HPM 100's, plugged the port, recapped per Mattd's instructions, and then put ANOTHER surround on the back?

Wild. Any pics? I would think two surrounds would fundamentally change the speakers, and not for the good.

Seems I'd have just picked up some Cerwins if I wanted thunder bass.

edit - you mean you just put more foam INSIDE the cab, behind the woofer, right? My apologies.

 

[nsxrush]

OnwardJames,

1) Moded as per MAtt's instructions

2) Replaced other caps

3) Replaced the original foam w/ audio foam, only in the back side (INSIDE THE CABINET)

4) Capped the port w/ audio foam (see pic)

5) Raised the speakers ~9-10" on cement block...toed them in, found the sweet spot.

And now having fun....Only thing remaining is adding new binding posts....so it can handle my cables rather large spades (don't think that will make change to sound)

And I am using PC audio (lot of work on that one...but not sure this is the place for it) But if anybody is interested send me a msg.

 

[onwardjames]

Nsxrush, thanks for the writeup, they look great! My 100 watt pair have simply been recapped with Dayton poly's, and that made a substantial difference.

 

[nsxrush]

HPM 150 X-over in HPM-100 ??

I got a chance to listen to my uncles HPM-150 last weekend....NOW MY HPM-100, don't sound so good anymore.

HPM-150:- relative to HPM-100...
Very tight bass
Very clear mids and highs....volume had no impact...(HPM-100, I lower the volume to enjoy....I prefer lower volume anyway)

So the question is:- Why are they so darn better..
Because
1) HPM-150 are powered by SS Pioneer (don't know the model)
OR
2) The X-over (different than HPM-100 even after MATTSD mod)

Has anybody tried HPM-150 X-over in HPM-100?
I have the ability to manu. HPM-150 X-over (already selected parts)

Interesting to know your opinions.

 

[Ed in Tx]

Only problem I see trying the 150 xover is the transformer that drives the super tweeter is a different ratio. 150 has a higher turns ratio yielding a higher step-up of the voltage. And the xover freq is lower to the super tweeter in the 150 too. Maybe some other slight differences but the super tweeter circuit stands out in my memory.

 

[imglocked]

3) Replaced the original foam w/ audio foam, only in the back side (INSIDE THE CABINET)

I am still not getting what you mean here; I have never opened my 100's, so is there loose 'stuffing' or solid foam in there? . . . thanks for your clarification, or to anyone else who can clear this up for me.

 

[nsxrush]

Ed in TX,

Yes I am aware of the transformer (actually from another thread on audiokarma..where u and Gordonx were involved in discussion)...

Also, I downloaded service manual for 150 and 100 from hifiengine.com...so I would select the correct values of Caps and coils. (if I decide to manu the 150 x-over)

Do you have any opinion on sound diff of 150 vs 100. I mean 12" woofer should have better control over 15" (and I hear 12" is a very good driver).....similar mid and tweeter drivers also....except the cross-over frequency cut-off differences and component values used.

Bigger question would be:- Are the mid-range and tweeter driver for 150 that diff to require diff values or these diff values make the sound better.



Imglock:-
The is original is fiber-glass foam...supposedly not as good as foam that you can buy from speaker DIY places (very cheap also)

 

[SuperVeeps]

Anyone have thoughts on this mod vs. the more faithful one outlined here:

http://audiokarma.org/forums/showthread.php?t=120454

??

I would like to recap my HPM-100s but I'm wondering which method to go with. The first thing I noticed when I got them is how they sound like PA loudspeakers. Way too harsh up close, even at lower volumes, but if I put them close to the floor in a large room, crank them up and stand way back, things even out and it sounds like a live concert.

Is that how they were designed to be used? And does the mod in this thread just make them more near-field friendly? Or is it a genuine improvement arrived at via modern speaker design knowledge that will help them perform better in all settings?

 

[Robint]

I am sitting listening to my HPM-100's as I write this. I modded my pair per this thread and I am very happy with the result. This mod is reversible if required. This mod lowers the crossover points, to my mind makes it smoother. The answer is to recap and replace the inductor per this thread, and do the other one per other thread and report which one you like.
As Ed in TX states :- Or... you modified the 100 crossover closer to the HPM-150 (which no one I'm aware of's ever complained about harshness) mid-tweeter crossover point (new=2400, 150=2600 Hz) , and lowered the mid to woofer lower, closer in the 150 crossover point too. The HPM-150 15.75" woofer to mid crosses at 750 Hz which makes sense, mid to tweeter 2600. From that I doubt you have to worry about power handling. 150s do just fine with those lower crossover points. If I was into it, 'd be tempted to lower the crossover to the super-tweeter too, make it a little more audible.

 

[nsxrush]

I Think I finally have the answer

Hi All,

I think I hit the jackpot yesterday. Please bare w/ me as I go thru the steps. And do read the posts before on what I had done so far...so you can understand all the mods.

So to mod the X-over closer to HPM 150...

1) Used 1.5mH inductor instead of 0.90mH (or 0.6mH in original)...this lowered the Xover point to 750Hz (similar to 150)

2) Used a 0.1mH inductor in series w/ 10uF capacitor (for Hipass....similar to HPM 150).....HPM 150 has different capacitor value

3) Replaced tweeter w/ SEAS, H1189 (from Meniscus audio)

This was all done 3 wks ago.

The base became very tight (over tight)..Highs were not bright (NOW I CAN INCREASE THE VOLUME AND IT WAS NOT HARSH)

But still the sound was not to my liking....specially after listening to HPM150s. I was almost ready to give up on the project.

So last night...I did something very simple...and that opened up the sound like I could not believe...The HPM-100 drivers are shinning thru'.
I THINK THE HPM-100 ARE OVER DAMPED W/ FOAM

1) I removed the original the foam from the MID-range (fills the whole cavity)....and replaced w/ 1" thick Audio foam..ONLY TO THE BACK OF THE CAVITY.

Could not believe how the mids opened up...the sound stage got more open too.

Still the BASS was too tight...so
2) I removed all the original foam from the BASS enclosure...left behind the Audio foam I had installed..on the back side only. Now the BASS opens up too.

The sound is not HPM150 (lots of other variables)....
But I think I am very happy that I stuck w/ modifying the HPM100s

I HIGHLY RECO THIS MOD TO ANYBODY.

Future mods that I MAY TRY
1) Foam all the corners in the BASS cabinet (leaving the back foam in place)

2) Replace 10uF capacitor w/ 8.5uF. Based on my calculations...w/ 10uF capacitor the Xover point to trebble is 2000Hz....I think that is low....should be around 2400.

 

[aussiedan]

Very informative thread. I'm curious about your mod Mattsd, sounds like it could be a good thing. I've spent a long time hunting down a pair of 200w versions and I'm loving them. At first I felt they lacked the highs of HPM-60's, but after a week of solid going, they make the 60's sound a bit tinny and empty.

I'm curious to see if anyone has bi-amped these or uses an active crossover to fine tune their preferred crossover points?

To be honest, I'm no engineer, I struggle to understand how to design a better crossover, but I'd like to look into matts mod in time

 

[tinkerer]

mattsd.....looks like in your rework you used a Polyester Film Mylar cap for the .15uf replacement instead of the rather large Jantzen Superior Cap that I've seen used on most reworks. Is that true? I have been looking for a suitable way to do that as the bundle of 3 large caps is somewhat hard to manage.

 

[mattsd]

mattsd.....looks like in your rework you used a Polyester Film Mylar cap for the .15uf replacement instead of the rather large Jantzen Superior Cap that I've seen used on most reworks. Is that true? I have been looking for a suitable way to do that as the bundle of 3 large caps is somewhat hard to manage.

I used a Panasonic polypropylene film cap there, a lot smaller and easier to manage. Part is 667-ECW-F2154JAQ from Mouser.

 

[tinkerer]

Thanks

 

[tinkerer]

I'm looking around for a coil that's physically smaller to better fit on the board. Looks like I can get a .82mH coil with .6 Ohm impedance, or a 1.0mH coil at 1.2 Ohm impedance. Both are 1.5" Diameter which is close to the original. So, my questions are this: How do those mH effect the crossover points? And what effect does the simple impedance of the coil have. According to my meter the original .6mH has around .3-.4 impedance.

 

[dc270]

I suspect the HPM 100 woofer was a page taken from the Aquaplas JBL 12" L-100 woofer. To get a woofer to reach to 1600 hz is quite a feat and to keep it smooth and not beaming. So long the mid can handle the lower xover point you might well have found something that works for your taste and amplification!

I agree with you that the xover point on the woofer should be lowered and a more powerful mid to be in place. Had the HPM 100 been a 3 way I think it could have been a much better system!
DC

 

[Gibsonian]

I'm looking around for a coil that's physically smaller to better fit on the board. Looks like I can get a .82mH coil with .6 Ohm impedance, or a 1.0mH coil at 1.2 Ohm impedance. Both are 1.5" Diameter which is close to the original. So, my questions are this: How do those mH effect the crossover points? And what effect does the simple impedance of the coil have. According to my meter the original .6mH has around .3-.4 impedance.

Increased resistance is more power wasted and heating of crossover components. IMO you are going in the wrong direction. Instead of increasing resistance of your crossover I would be looking at decreasing it. The crossover does not have to be on that little board Pioneer placed in there, you can place it anywhere in the cabinet.

That being said I do not know what your goals are. If it is to improve the sound I would be going with better components and less resistance, if degrading sound, I'd go with the increased resistance.