Performance series + DIY

[skeptical1]

Well, I bought some new PT800's off Ebay in December, and started tinkering soon after. Actually, I immediately decided that $2200 for a pair of PS1400's wasn't gonna happen. Besides I had already been biamping in my current set-up, and had some woofs available. SO..... I bought some Parts Express boxes and threw my Le10H-1's in them. I know a lot of folks consider 10's too small for bass, but I think these are the most incredible drivers made. Period. The Le10H-1 has never sounded like a 10" woofer to me. If you set these guys up for bass they will deliver. So, after some tuning to get things the way I like em, I started doing a lot of listening.
The Pt800's are some really, really clean sounding speakers. But, I never,ever emotionally connected to the music while listening to them.. I listened to them and played them constantly for several weeks, giving them ample break in time, but there was something about them that I couldn't relate too. The only flaws that I could identify were a treble that was a little too emphasized for my taste( on occasion), and I thought most importantly, that vocals just did not sound natural. In particular male vocals would sometimes sound funny. Anyway, I have what I consider a pretty good rig and I have never had the cash or felt the desire to spend big bucks on speakers. I had hoped the PT800's would be all things for me- but they weren't. Certainly fine speakers for what I had paid for them, but really not worthy of what I was driving them with.
So that's the background, and here's the story. So I decided to build some xovers according to the schematics with all premium components. It was not a cheap affair- about $700 in parts, but the results are easily worth it. The improvement was apparent immediately upon installation, but I still did not consider them my last stop for a while until they had broke in for a couple of weeks. Not after the couple weeks break in the sound has become so good that I often cannot imagine the sound being better! And that is a first of sorts for me. I have played them now many times since they have opened up for me, to be sure that it wasn't the moment ( or the wine), and indeed they impress the hell out of me every time I play them.

I have some pics. The first is the xover that I built in the outboard box that I built to house it, compared to the stock xover. The Mundorf 8.2 mfd cap is about half the size of the entire stock xover network alone! The second pic shows the xover box on top of the bassss unit behind the PT800. I built the xover boxes to fit perfectly there. I then filled the with sand and covered them.

Short story- The improved xover really release the true potential of these speakers.

[edgewound]

Nice work...very nice.

[skeptical1]

Oh yeah, That was the wrong pic. this is the one with the box uncovered. And I forgot to mention that since I already had 3 runs of my favorite speaker cable, I went ahead and made the crossovers bi-wirable.

[4313B]

Yeah Baby! :applaud:





Let's see some pictures of those LE10's too please :)

I know a lot of folks consider 10's too small for bass, but I think these are the most incredible drivers made. Period.

Um, no...
Me too. I have six of them.

[Earl K]

Great Story ! Great UpGrade :applaud:


Let's see some pictures of those LE10's too please

Yes indeed , lets see those little 10" thumpers :p

[skeptical1]

Hey, Thanks guys. I knew there were other Le10H-1 fans here. I have put an honest 800 watts into the LE10h-1's on peaks when listening to Mettalica, or Tool. Not to mention they are probably the most natural sounding driver I know of. Everything sounds lifelike through them.
Here's a shot from the driver's seat.

[4313B]

The guy reflected in the fireplace looks weird, his feet are pointing in, but everything else looks great!

[skeptical1]

Oh yes, as far as bass goes, I love powerful bass- but it has to be fast and articulate for me. I also have 2 subs in my system- 1 is always off, and the other is only used on the rare recording that I think needs a little boost- and it is set on 2. the Le10h-1's cover all 95% of the time.

My listening is pretty much 2 channel only , although I do use for movies and sports sometimes.

[skeptical1]

Yeah, the guy in the reflection is definitely weird- one of those obsessive audiophile types. But I think the pigeon toed thing is a matter of reflection.

[4313B]

Yeah, the guy in the reflection is definitely weird- one of those obsessive audiophile types. But I think the pigeon toed thing is a matter of reflection.;)


Well, I think this is really great and thanks for posting it. :cheers:

[Earl K]

The second pic shows the xover box on top of the bassss unit behind the PT800. I built the xover boxes to fit perfectly there. I then filled the with sand and covered them.

- Among a few others ( including the Westies ) , I know that Jean will be pleased with the sand dampening .

- I see the 2 sub boxes but not any actual le10h woofs . Are there two per box ?

- Which portion of the new networks' circuit, uses the Mundorfs ?


:)

[Titanium Dome]

Excellent and inspiring.

[skeptical1]

Hi Earl, 1 Le10 per box. They are the 2 cu. ft. boxes. I used the parts express flared ports and finally wound up with a 3" length, I think.
The crossovers utilize solen caps in the two shunt positions 56uf. & 13 uf, with Kimbercaps for the bypass. All other caps were Mundorf Surpreme, with Mundorf PIO for Bypass. All resistors are Mills 12w, and all inductors are Jantzens, from Parts Express.

[briang]

Nice work!:coolness:

[Titanium Dome]

Dump out all the sand and get a closer, straight on shot of your handiwork? Also, the underside of the project board?

That's a fascinating exercise, and it deserves more exposure.

[skeptical1]

Fortunately I had these pics. I used a pice of 1/4 inch plywood for the mounting board. The pic with the board in the box shows that it is resting on a layer of sand before I covered them with sand.

If you are looking at the schematic, while viewing these, you can see where I tried to keep the components for each driver in some sort of order, with the woofer on the left , mid in the center, tweeter on the right, for the pic of the crossover in the box. The underside of the board is flipped left to right, and you can sort of tell that by the color of the wire ties.

For installation, I just removed the binding posts and crossover from the PT800, and ran the wires in through the holes where the binding posts are. So I could easily put everything back to stock, with no signs of molestation if I wanted to.

But I don't forsee that happening........

[Don Mascali]

Impressive:applaud:

[Titanium Dome]

I see things that were hidden before. Thank you!

[MJC]

looking at that box, I will probably need to built a slightly bigger box for a CC xo, as the number of caps will double.
Using Mills resistors, Jantzen coils and Solen caps will cost $450~475 for a pair of PT800s. Or about 50% more than the cost of my pair of CC xo for the L212s.

[4313B]

looking at that box, I will probably need to built a slightly bigger box for a CC xo, as the number of caps will double.It's easy to see why JBL didn't cc them. No room at all.

[MJC]

It's easy to see why JBL didn't cc them. No room at all.
Although the PT800s are about the same size as the L212s, it was easy to CC L212 with its open back. I cut up three cards the same size as the original, one for each driver. Mounted one to the left side, one to the right side and one accross the opening, to the wide side of the speaker array.
For stand alone PT800s JBL could have provided bases similar to the L212 bases and housed the cc xo inside, and/or added them to the PS1400.

There is one thing I would not have thought of, until reading through this thread, adding sand to the box, good idea.

[MJC]

While going over the xo for the PT800s to develop a parts list for cc xo, it became obvious that I would have to mate caps in parallel to get the capacitance values needed for each half of each series pair.
Then the question that came to me, is it better for each cap, of parallel pairs to be of equal value, or at least close, or to use totally unmatched, in value, for each parallel pair?
To my way of thinking, it would be better to have parallel pairs as close as possible to equal capacitance for best results. Would this be right?
Or does it make no difference?

[toddalin]

While going over the xo for the PT800s to develop a parts list for cc xo, it became obvious that I would have to mate caps in parallel to get the capacitance values needed for each half of each series pair.
Then the question that came to me, is it better for each cap, of parallel pairs to be of equal value, or at least close, or to use totally unmatched, in value, for each parallel pair?
To my way of thinking, it would be better to have parallel pairs as close as possible to equal capacitance for best results. Would this be right?

Interesting question and one that I just faced. When I built the XOs for my L,C,R with LE175-HL-91s, the mids called for 16.5 mF cap. I wanted to stay with one brand and use ALL Solens and made up this value using two 8.2 mF Solens (16.4 mF total).

When I ordered parts to build the XOs for the four surrounds that are to use 2425J, I also wanted to use the two 8.2 mF Solens. But I only ordered enough parts to build one of the surround XOs (and a few extra parts to get quanty discount where applicable) with the reasoning that I could build one and "tweek" it before ordering the parts for the other three.

Meanwhile, Domino was building similar (but not identical) XOs for his project that also use the 16.5 mF cap for the horn. In his case, he used a 16 mF Solen and a 0.47 mF Janzen (16.47 mF total).

Domino wasn't happy with the sound and decided to replace them with AuraCaps, so sent me the Solen/Janzens. So one set of surrounds will use two 8.2 mF Solens while the other two will use the 16 mF Solen and 0.47 Janzens. Also Domino sent me four 1.5 mF Janzens that will be used in the HF compensation network. (The L,C,R use Solens in the tweeter network.)

In my case, all caps (Solen and Janzen) in all XOs receive Theta Audio-Cap 0.01 mF bypass caps, that in theory, should impart a similar (but not idential) sonic signature on all of the caps regardless of brand.

I really doubt that I will hear a difference because of brand or because of the way the values were paired. :o:

In theory though, I would think that a large and small cap together could outperform two medium caps, much in the same way that a by-pass cap works. I had always heard (maybe incorrecly) that a smaller cap can react faster to transients than a larger cap.

[4313B]

While going over the xo for the PT800s to develop a parts list for cc xo, it became obvious that I would have to mate caps in parallel to get the capacitance values needed for each half of each series pair.
Then the question that came to me, is it better for each cap, of parallel pairs to be of equal value, or at least close, or to use totally unmatched, in value, for each parallel pair?
To my way of thinking, it would be better to have parallel pairs as close as possible to equal capacitance for best results. Would this be right?
Or does it make no difference?Here's the matrix I posted a few years ago for the Solen pairs. I just select the two closest value pairs.

[mikebake]

You had/have L212's; did you give us a comparison somewhere to the PT800's? Also, do you still have the sub1500's?

[MJC]

You had/have L212's; did you give us a comparison somewhere to the PT800's? Also, do you still have the sub1500's?
I've still got all 7 L212s, one pair cc, which I have setup with Citation amps and a turntable.
And I still have the pair of SUB1500s in the HT.
As you might expect, the L212 and PT800 are quite similar, if for no other reason, than they more/less share the same basic design. Both 3-way in boxes that are close to being the same size.
But when it comes to movie soundtracks, the PT800s are much faster, I suppose due to them being 100% Ti.
One slight difference, in comparing the main L/R of each, is that the main L212 were cc, where as the PT800s are stock.
The PT800 seems to be more airy, open, althought the cc pair of L212 are also much more so than when they had original xo.

AS Ti Dome has stated, on another forum,
In 5.1 multichannel music (DTS, DD, DVDA, SACD) the sound is immaculate. No sub is needed whatsoever. The sound is full, open, spacious, refined, clear, and dynamic. It's truly the most seamless musical experience I've had outside of a concert hall or music venue. In some cases, it's better than the live show.
But as skeptical 1, who started this thread, almost a year ago, has said, upgrading the xo improved an already very good system. Although he only built a by-pass xo, using higher end components. But I plan to build cc xos, for the main L/R first and then probably for the center.
At this time I think I'll have to skip doing the surround PT800s, as they are hanging on the walls, as there isn't enough room inside the PT800 boxes. Or so it would seem. I suppose I could cut out the sheetrock behind the speakers and mount a the xo boxes in the wall and re-mount the PT800 in front.

This is how the front end of the HT looks now. Notice that the sub boxes are square, as they were built to match the L212 boxes. I bought a pair of PT800 grilles for the subs.

[MJC]

One thing I've never had the chance to do is compare a PT800/PS1400 stack to the PT800/SUB1500 stack, as I don't have even one PS1400.
Although I get a very good bass with a Crown K2 amp driving the SUB1500s I can't drive the stacks as a unified full range speaker, as can be done with the PS1400 in the mix.
If I were to replace the Crown with plate amps and use their xo then I could run a true full range, bi-amped stack. Although I don't know if there would be any advantage compared to using the K2 amp and the bass management in the H/K receiver.