Sonic Heaven

[ClaudeJ1]

<<<<djk:

I've got two pair of the EV HP940 with the DH1A, theyt're real nice aren't they?

I've also got three pair of the EV HP640, they work better for PA.

How do you like your Peavey MB horns?>>>

I'm
in sonic heaven with these things. I lined up all the voice coils of
the MB-1, the HP940/DH1A, and the JBL, smack into the corner on top of
the MWMS, so I'm close to time aligned, . I hear much better ambience
in the recordings and incredible detail. Got rid of the attenuating
resistors, Zobel, etc. in the JBL Xover, since the MB-1 efficiency is
at about 109 db/watt I needed to match up everything else to it.

Just
finished my Xover tweaks today. Get this, I'm running all 1st order
slopes, just a 3uF cap on the JBL, wide open, a Bob Crites autoformer
at -4 db on the DH1A with a 12 uF cap. It's ruler flat from 1K to 6K
without CD eq., so i'm letting the natural 6 db/oct. rolloff
happen...right into the super tweeter. On the MB-1, I'm using the
chokes from a Klipsch KG-4 Xover in series 1 mH + 0.5 mH. I set my
receiver to "small speaker" so the signal is a 150 Hz Highpass into the
MB-1. The double set of MWMS take over at 150 Hz down from the mono
signal of the sub out and are fed by 4 discrete channel of Hafler amps.
I had to turn those up a little to mate with the MB-1. It's all cheap,
simple, and insanely efficient.

I used my friend's RTA setup
and those 5 horns/channel together are a smooth as a mile of velvet
(with the exception of the 55 Hz hump in the MWMS). I'm hearing detail,
depth, ambience, definition, and dynamic IMPACT like I've never heard
before on any speaker, including the Jubilees, Khorns, and the
Palladiums. There is no harshness of any kind at any volume. It all
sound so real, it'a almost scary.

The MB-1/HP940 have replaced my
LaScalas (no more 160 Hz hump to color the sound). They more efficient
and lower distortion, as the MB-1 makes a better MidBass horn than the
LS bass horn does (compromises). I get louder and with greater detail
at a lower volume control setting. Plus I'm finding myself listening at
about 3 db less than before BECAUSE of the extra detail and imaging.
Amazing what big horns with simple Xovers will do. Maybe Bruce Edgar
was right about simple 1st order networks sounding best. In my case,
there is not EQ anywhere, just running on the flat portions of the
horns and gently crossing to other horns. Now this is no slam on a
LaScala, which is still my favorite compromise in the Klipsch Heritage
line..........especially in the age of subwwofers. Other than low WAF
setup (not as insane as some others in the world, but close), nothing
beats an old pair LaScalas with fresh caps on an A networkwith Bob
Crites Tweeters and his 4500 mod, K-43, and your favorite subwoofer for
great sound and ease of setup.

THE MB-1's bring out subtle
nuance in vocals, piano, and drum attacks like never before, since
there is no Xover point in the most important range (150 to 1.2 Khz)
which they serve very well (probably because they have rally big phase
plug and a big throat). I'm really glad I took a chance on these. I
have an extra pair in the garage, just in case...............LOL.

[Erik Mandaville]

"Just finished my Xover tweaks today. Get this, I'm running all 1st order slopes, just a 3uF cap on the JBL, wide open,"

Great, I think that works very well, too, and my findings have been the same about the improvement at lower volume settings. Positive feedback did an interview with Bruce Edgar, and I remember in that he mentioned his preference for very simple crossovers, as well.

Did you connect the 3uf cap directly to the input or after the 12uf capacitor at the top of the autoformer? For me, the direct connection is a change for the better.

Good work -

Erik

[Erik Mandaville]

"Got rid of the attenuating resistors, Zobel, etc. in the JBL Xover,"

That is honestly refreshing to hear. I have read numerous times where modeling was done with specific reference to this -- where the designer wanted to do away with any circuit that might impose losses. Even at the cost of linear measured response (which in one case I remember had been described as 'boring' and uninvolving compared to plots that revealed certain mild bumps and deviations at specific frequencies. Simplicity can sometimes be very difficult to improve upon, and what is linear may not always equate with 'good' sound reproduction. The other side of the coin always remains, though. Subjectivity is such a significant element in all of this.

[ClaudeJ1]

"Just finished my Xover tweaks today. Get this, I'm running all 1st order slopes, just a 3uF cap on the JBL, wide open,"

Great, I think that works very well, too, and my findings have been the same about the improvement at lower volume settings. Positive feedback did an interview with Bruce Edgar, and I remember in that he mentioned his preference for very simple crossovers, as well.

Did you connect the 3uf cap directly to the input or after the 12uf capacitor at the top of the autoformer? For me, the direct connection is a change for the better.

Good work -

Erik

I connected the cap to the autoformer, then the autoformer -4 db tap to the driver. I will try it the other way, then, just to see.

What is better about it?

[ClaudeJ1]

"Got rid of the attenuating resistors, Zobel, etc. in the JBL Xover,"

That is honestly refreshing to hear. I have read numerous times where modeling was done with specific reference to this -- where the designer wanted to do away with any circuit that might impose losses. Even at the cost of linear measured response (which in one case I remember had been described as 'boring' and uninvolving compared to plots that revealed certain mild bumps and deviations at specific frequencies. Simplicity can sometimes be very difficult to improve upon, and what is linear may not always equate with 'good' sound reproduction. The other side of the coin always remains, though. Subjectivity is such a significant element in all of this.

There are no mild bumps, really that would show up based on Xover order, etc. except below 300 Hz, where the room modes kick in. Otherwise, the Midbass, Treble and super tweeter horns are all CD types, which only require EQ past their natural rolloffs. Since I don't use them past their natural rolloffs, , but cross to other drivers, it's not an issue.

If you look at the K-55 driver on the Khorn and LaScala (others too), there is no rolloff choke, PWK just went with the mass rolloff of the phenolic diaphragm at 6k, when crossed to the K-77 with first order on the A and 3rd order on the AA. The reason they want to higher order with back to back zeners on the AA is because people were frying tweeters. While it's perfectly save to ram +12 db of treble boos at 15 Khz. in the DH1A driver (I did it before), I'd rather use a 2404, which handles the super high frequencies above 15K without any ringing peaks, which ALL compression drivers have up there. It's real tricky to do high order Xovers with passives, so I avoid that also. I much prefer active Linkwitz-Riley, with time delays and PEQ's but event then, it's mild. I don't want to ram stuff into my drivers that they don't want to do naturally.

PWK's biggest complaint was the RCA connectors, which disconnect ground while keeping the positive still hooked up, so when you unplug a pre-amp connection, accidentally or on purpose, the signal slams the supply rail and the power amp fries the tweeter with a quick squeal. This was a solution for a disastrous condition, not necessarily because it sounded better.

In fact, funny story, when I was at PWK's house (one fine day in 1985), he was doing just that with his connections and the system was squealing while he was swearing at it, as he was swapping connections in the closet, so he was one to pull RCA plugs on purpose. LOL. He played his own symphonic recordings for me. All the stuff he published, he did. Including the resistor box for the 3rd channel and the 2 false corners. His Khorns and center Belle were oiled walnut right from the factory floor, nothing custom at all............FYI.

I guess there are issues with phase in using autoformers vs. L pads or resistors, which only turn the extra energy to heat rather than increasing circuit impedance, but I have not A/B'd those yet, and may not, since what I have sounds so darn great!

[Erik Mandaville]

"I connected the cap to the autoformer, then the autoformer -4 db tap to the driver. I will try it the other way, then, just to see.

What is better about it?"

For you it may not necessarily be better. To me it was. It also removes the tweeter from any association with the autoformer and input capacitor. That capacitor may be a source of slightly increased series resistance. A more modern way of connecting the tweeter filter, which is how some of the later networks were done, is to connect it directly to the amplifier input, with only the single capacitor between it and the amplifier. It simplifies the design, and may provide slightly more energy to the tweeter. Connected that way, it's a true first order network. As far as autoformers and L-pads: The older designs used autoformers. They worked and continue to work. The newer designs don't use them any longer, although I don't agree it's because Klipsch is trying to focus on profit at the cost of performance in doing so. If what the autoformer contributed to the sound was so significant, it seems to me that the slightly higher cost would be judged worthwhile. Altec and JBL used resistive L-pads, including variable types. It's a design choice, and Mr. Klipsch preferred the autoformer.

If you decided to try the network without it, some changes have to be made to off-set the altered reflected impedance. I prefer resistor L-pads, and I don't agree with the traditional idea that they are inferior. I compared them, and just use what sounds best to me. This doesn't mean I don't respect PWK. In choosing two resistors over a heavy winding of wire, I've actually changed HIS original design far less than those who swap out the entire midrange branch of the speaker, including both the driver and the horn -- along with a new tweeter. I would argue that the midrange branch of a system like the Klipschorn or La Scala is responsible for a signficantly greater percentage of the overall sound of the speaker than does the method of attenuation it uses -- aka: autoformer. That's why I have kept that part of the speaker original. A complete alteration of the entire top section of the speaker weakens the argument, IMO, that choosing a couple of resistors over a multi-tapped choke is invalid. As I said, I respect PWK's choice; I just suppose I process sound differently.

That's all! It sounds like you're enjoying the changes you made. That's good.

Erik

[Erik Mandaville]

"In fact, funny story, when I was at PWK's house (one fine day in 1985), he was doing just that with his connections and the system was squealing while he was swearing at it, as he was swapping connections in the closet, so he was one to pull RCA plugs on purpose. LOL. He played his own symphonic recordings for me. All the stuff he published, he did. Including the resistor box for the 3rd channel and the 2 false corners. His Khorns and center Belle were oiled walnut right from the factory floor, nothing custom at all............FYI."

That must have been a neat experience! All I had at that time was the literature for the speakers. I longed for a pair of Heresies back then. The closest sound I could find that was like them was a pair of Cerwin Vegas. They actually weren't too bad, but they weren't the Heresies.

Erik

[fenderbender]

I'm glad you two know what the heck your talking about [][][] that , or it's the fact I'm on vacation this week and I'm already on my 5th...6th margarita tonight.

[Erik Mandaville]

And FWIW: I have no disagreement or problems with anyone changing their original Klipsch speakers in any way they may choose. There are lots of guys/gals who have altered them with completely different drivers, horn lenses, crossover designs, and so forth. Those are in fact the parts that provide the characteristic Klipsch Heritage sound. My premise is simply that the autoformer is of less importance, IMO, in what it contributed to that sound.

Have fun!

Erik

[Kevmosmith]

Hi Erik,

I think I will give this a try. Does wiring directly from the input to the tweeter cap require a different value capacitor or can you use the same value? Would that work equally well for the A and AA networks? Thanks in advance.

Kevin

[Erik Mandaville]

Hi, Kevin:

I envy your comparative handful of posts. Honestly. When I see the close to 5,000 of mine it makes me think I need to be doing other things.

So. This is really a very simple thing to do. On the Type A, you remove the connection between tap #5 on the autoformer to its connection on the 2uf capacitor. Leave the other connection on that same cap that leads to the (+) tweeter connection. The now-free side of the 2uf cap (the side that previously was connected to the top of the autoformer) is instead connected straight to the (+) input of the crossover. Another way to make that connection would be to run a lead to the input end (not the autoformer end) of the 13uf capacitor, because it also goes to the crossover input.

For a first-order network with an 8 ohm driver @ 6,000Hz, the calculated series capacitance is a little over 3uf. On the network below to help illustrate this for you, I'm using a 3uf motor run that is paralleled by a .33uf poly film type. You already have the existing 2uf, and can get by to try it by paralleling a 1uf capacitor with it. If you don't have one, Radio Shack sells a mylar in that value which would work fine (just cost too much).

I've been connecting tweeter networks like this, including these old Heritage types for years. Nothing bad will happen -- you'll just think it worthwhile, or not, just as some would prefer to leave it where it is because it sounds 'better' for whatever reason.

The type AA is a 3rd order, which can be done the same way. DJK and I arrived at almost identical values for the three elements needed. Let me double check this, but I'm quite sure the single inductor, which is connected to ground on one end and between the two series capacitor on the other is close enough to what is needed. You would just change the cap values, and you'll end up with exactly the HF branch that I made on the second crossover shown. In both cases, the crossover point is the same, Kevin. It's just simplifying the design by connecting straight to the input, which is common practice.

Like ANY of these modifications, if it's not for you, it's really easy to put things back to how they were.

Erik

[Erik Mandaville]

Kevin: For the 3rd order on the type AA, it was for the lower crossover point, not 6,000Hz. I need to look at that again for the different values that would be needed. I know what tweeter you have, and a 3rd order network is actually what is specified, but for 3.5kHz.

Erik

[Kevmosmith]

Erik -

I think the difference in the number of posts is I have asked 80+ questions and you have provided 4,660 solutions.

I will give it a go!

Thanks - Kevin

[ClaudeJ1]

And FWIW: I have no disagreement or problems with anyone changing their original Klipsch speakers in any way they may choose. There are lots of guys/gals who have altered them with completely different drivers, horn lenses, crossover designs, and so forth. Those are in fact the parts that provide the characteristic Klipsch Heritage sound. My premise is simply that the autoformer is of less importance, IMO, in what it contributed to that sound.

Have fun!

Erik

Ah, I see from your prior post what you mean. On my Khorns, all I did was refresh the caps and left the AA's original. When I put the JBL 2404's on top, the tweeter section of the AA sounded terrible, so I built John Warren's 3rd order Xover with Zobel exactly like his article. I ended up using the same resistor values as he did after going up and down with them. I left the original K-77's in the Khorn disconnected.

I sold the Khorns to buy MWMS bottoms after hearing them with Roy Delgado's amazing K-402 horn with the K-69 driver (the upper half of a Jubilee). I preferred the MWM's to the Jubilee bottom. With the leftover cash from my Khorn sale, I got 2 more LaScalas to use on top of the MWMS bins, which sounded great using the exact same JBL tweeters with the Warren Xover. That combo sounded even better than the Khorns ever did. The tweeter section was fed directly from the amp as a totally self-contained unit, just like the LaScala, except the K77's were also disconnected. I was only using the midbass and K400/K55V portion of the LS as vanilla stock hookup.

I decided I wanted even better midbass definition and I coudn't find any Klipsch MSSM midbass uint after looking for 6 months. I had heard from others on the Web that the Peavey MB-1 was one of the best midbass horns ever made and I found 2 pairs 2 weeks apart from each other, one pair only 1 1/2 hours from home. I matched all the other gains to it, and for best sound, I had to simply use a single capacitor on the same old JBL 2404 to increase it's output. It is still fed directly from the amplifier as a self-contained unit. I ended up taking out all 7 of those other premium part I had bought and only used the 3 uF the cap, which was calculated as the requred value. It worked perfectly, and the 2404 got louder to keep up with the DH1A/HP940, which had to be tamed by the Crites autoformer. Basicall all the drivers are separate. PWK's original Jubilee used a 2" driver on it's horn. Roy's commercial K402, for the Jubilee, uses a 2" throat driver also. Roy tested one of my DH1A drivers in the Klipsch chamber during last year's pilgrimage and told me it was a very good driver. So, because of his blessing, I decided to keep them and use them eventually. I'm glad I did because I get the most real life sound out of them from 1K-6Khz along with the JBL tweeter.........scary detail.

So I never really messed with the original Khorns or LaScalas, just dsconnected the tweeter. While I like the Klipsch heritage sound very much, what I put together (using only my Khorn money the whole time) is FAR superior, sonically, but huge and ugly, hence, the title of the original post.

[Erik Mandaville]

Claude:

"So I never really messed with the original Khorns or LaScalas, just dsconnected the tweeter. While I like the Klipsch heritage sound very much, what I put together (using only my Khorn money the whole time) is FAR superior, sonically, but huge and ugly, hence, the title of the original post."

Absolutely, I understand what you are saying. Truly, there is nothing wrong with modifying these great old speakers in any way one wishes to. I'm using new tweeters myself in ours, but I just like they way Bob's solution works. Some here have thought it cliche' to make reference to the comments of spouses, which is fine for them, but when I was contemplating a complete reconfiguration of our Klipschorn top section, my wife, who is very tolerant and supportive, gently put her foot down. The point was that we were starting to drastically change a design that is already very good, and on which a certain very well-respected designer and thinker had invested a great deal of time and energy. The point is valid, I think, and at the same time I'm guilty myself! I've altered the crossovers (slightly) by choosing to use a resistive L-pad over the autoformer; I've chosen a new tweeter that is quite different from the originals; and thought the speaker sounded less 'muffled' with the grille fabric removed. I've changed them too because the changes I made sound better to me. I also installed acoustic damping material in our Heresies, which to me was an improvement (you just don't know it's there!).

Similarly, the very competent and talented woman who designed our back-loaded Lowther horns suggested to me strongly that I fill all the cabinet voids with sand to deaden the enclosure. With lots of effort I did it, turned the system on, and was met by a sound that I just couldn't live with. To me, it ruined it, even though in my mind I understood the importance of the theory of a loudspeaker cabinet that was as inert as possible. This means that some of what I like about the sound of the Lowthers is, in fact, the way in which the cabinet contributes and COLORS the sound -- just like every single component, passive or active, in the signal path -- sources, preamps (passive or active), amplifiers, transducers (phono and loudspeaker), etc.

The point I have tried to make for too long is that in light of what CAN and has been done as far as manipulating and changing an original and classic design, deciding that a simple resistor L-pad sounds better than a multi-tapped choke is relatively benign. I also am very familiar with PWK's research on this, and still prefer to stick with what sounds best to me -- just as those who have installed different horns and drivers in their La scalas and Klipschorn top hats. To my knowledge, he never published any paper or modification that suggested the use of squawkers and tweeters from companies such as Altec and JBL. (I say this jokingly).

Enjoy what you have, including the experimentation with new components. We all have our own objectives and preferences as far as what we choose to do to make these speakers sound better.

Kevin: On the picture I posted, the leads are color-coded. The yellow connections, that may be a little hard to see, are for the tweeter. There was a schematic of a Heresy II recently posted, where the tweeter section also completely bypassed the autoformer. Interesting, it's also I higher order circuit, which can also have the effect of some insertion loss, which in turn can thus be a way of balancing and equalizing driver outputs. If you don't care for the result (which will probably be subtle), it's always easy to put things back the way they were.

Erik

[ClaudeJ1]

FYI, I just got done listening to the 20 bit remaster of classic, Kind of Blue, by the Miles Davis sextet. That is one heavenly recording session, not even considering it was made over 49 years ago. With my new setup, it's like I invited all the spirits of the musicians back into my room to play. It's the most realistic presentation of that recording I ever heard. Every nuance of that recording is revealed, brushes on snare and cymbals, the dynamic of the saxes, the subtleties of Bill Evans piano and Miles Davis muted trumpet right down the middle with the Paul Chambers bass echoing in the ambience of the studio. It's like a time machine.

[fenderbender]

Hey Claude...

,p> if you don't mind....were is the 20 bit remaster from??? which format? I love that album.....

[ClaudeJ1]

Hey Claude...

,p> if you don't mind....were is the 20 bit remaster from??? which format? I love that album.....

Columbia, 2004, it's a DVD video on one side with interviews with several jazz lover, players, and stars. Rare footage, photos, and audio from the actual recording session, and an interview with the drummer, Jimmy Cobb, the last survivor from the session, since passed on.

Not sure about the 20-bit, I think I read that from the last version I gave away as a gift. I have given people lots of these because it's so good.

[fenderbender]

thanks Claude....I'll keep my eyes open for a copy.....