Jubilee and passive networks - long and possibly inflammatory

[greg928gts]

Richard (coytee) sent me a pair of passive networks that Dean built to try on my Jubilees and I said I would post my thoughts about them here.

I’ve been asked to give my impressions of the Jubilees that I own. Those impressions will contain positive comments as well as negative. If you don’t want to hear negative things about Jubilees, or if you’re the type of person that ignores the good things that someone has to say about something and only focuses on the bad, and that upsets you, you should close this thread and go somewhere else. I’m sure what I’ve said here will ruffle feathers and my words will be used against me by those of you who look to argue with someone’s opinion, but I don’t care, I can take it, I’m going to let my voice be heard on this open forum. In fact, even with all the goading that I'm sure will follow, I may not even post again in this thread.

It only took about 5 seconds as I walked back to sit on the couch. The passive networks sound much better than any of the active setups that I used. It's like the speaker instantly became smoother sounding and more coherent. I was hearing music. O.k., now to sit down and evaluate what I’m hearing. . . .

It had been a long day. I’ve been reveneering my own Khorns over the last few months and I have plans to replace all the internal components with upgrades, but my friend Karl had never heard Khorns and I wanted him to hear what stock Khorns sounded like before I go messing with mine. So I put mine back together with the stock components and set them up in my living room. We spent a couple of hours listening to various types of music and then decided that it was time to listen to the Jubilees with the passive crossovers.

It took a few hours to bring the Jubs over from the shop and bring the Khorns back to the shop. We got the Jubs hooked up with the passive networks and we were using a NOSValves rebuilt Scott 299A, about 17 watts per channel. Karl was very impressed with the Khorns and I think equally so with the Jubilees. He kept saying how the same songs we listened to on the Khorns sounded so different on the Jubs. He thought the Jubs went deeper but the bass was not as focused, almost a little boomy. He noted how the Khorn bass doesn’t come right at you like the Jubs, but more from around the whole room. He didn’t say much about the high end, just that it was different. I think he needed more time with them, but he did say that his impressions have completely changed since hearing the Jubs in my small room at my shop. That small room didn’t do the Jubs justice, I probably shouldn’t have even invited him over to hear them in there. The more I listened to them in that tiny room, the more I realized how many problems there were. My living room, which was built with Khorns in mind, is a much better room for Jubs (although not according to my wife, WAF!)

Karl had to leave after a few songs, but I listened for another hour or so. I offer the following as my updated impressions of the Jubilees, with passive networks.

My thoughts on the Jub bass bins are that they sound better loud than soft. At lower volumes, they are a little muddy sounding, and even with higher volume levels I’ve noticed some boominess and smearing in the bass tones that I would not have noticed if it were not for the Jamboree bass bins that I’ve built and tested against the Jubs. But there’s no denying, when you crank up the Jubs, they produce a huge authoritative bass that is very impressive.

The whole Jubilee system is voiced lower than the Khorn, which is notable in the deep bass and how strong it is compared to the Khorn, but also maybe more importantly on the mid-bass frequencies. Instruments like Alto Saxophones and piano take on a decidedly deeper and richer tone and vocals sound more realistic than the Khorns. This deeper voicing, both in deep bass and in the richer, warmer midrange is why I consider the Jubilees to be better overall than the Khorns, even modified Khorns that I’ve heard with Trachorns and Beyma tweeters. I like more bass than stock Khorns provide, so I really like that part of the Jubilee.

I just don’t like the K402/K69. The farther down I attenuate it, the better I like it. When it’s up high enough so that it’s properly mixed with the bass bin, it has inherent problems that I just don’t like. When I get it down low enough so that those problems go away, the horn is really not hot enough in the mix and the clarity of the midrange really suffers. It’s similar to the experimenting I’ve done with adjusting the midrange output of the K400/K55 on Khorns. Turning down the mid horn on Khorns is a way to soften them, to smooth them out and make them sound more “hi fi”. But at a cost in clarity and realism that is just not worth it to me.

When it comes to the high frequencies coming out of the K402/K69 (the frequencies that normally come out of the tweeter in a 3-way system) there’s a real lack of the very high highs coming from the horn, say from 8K on up, or perhaps it's that the high highs are being overpowered by other frequencies. What I hear instead of smooth high highs, is an aggressive sound from frequencies that seem to be an octave or so lower that is harsh and sounds over-driven. It’s the kind of sound you hear when cymbals are almost sizzly sounding, instead of being clear and detailed. I think this sound is consistent with what you get when a speaker is being manipulated electronically and frequencies are being boosted beyond what the speaker is really capable of producing on its own. When I listen to the K402/K69, the harshness in the high end sounds like a speaker being pushed too hard in that frequency range. I think this is a good example of how a test with a graph might look good to the person doing the testing, but the end result tested by the human ear is quite different.

Like many other people, I hear harshness in Khorns too. Perhaps a little lower in the frequency range, coming from the mid horn I would say, but that harshness is there, and it’s what so many people over the years have been trying to modify with the Khorns to make them sound better. I would say the same thing about the Jubilee.

I think the Jubilee high end would be much better if it had a tweeter and a midrange horn that didn’t require processing beyond a simple crossover network. I think some of you Jubilee owners out there would be surprised at how good the Jubilee bass bin would sound with a wooden tractrix horn with a quality 2” driver, a Beyma CP-25 tweeter and a simple crossover network. Or, the type of two-way setup that Mike Klementovich is using, a Martinelli wood horn with a Beyma CP750ND on the Jub bass bins with a simple passive crossover network. Or HECK, how about a Khorn top end with a Cornwall crossover?

Overall I'm impressed with the Jubilee and disappointed at the same time. I've negotiated two more weeks (WAF) for them to be in the living room, and I intend to enjoy the heck out of them while they're there. Then it's back to modifying my Khorns, which are allowed in the living room anytime. I also intend to continue my quest to build a really nice fully horn-loaded loudspeaker around the Jamboree bass bins that require no more processing than is found in a Khorn, and will also be allowed in my living room.

Greg

[greg928gts]

The network to the right of the Scott 299 is for both low frequency cabinets, the network to the left is for the left K402.

Greg

[laager]

Interesting. I'm somewhat surprised that anyone would consider buying Jubilees without the KPT-Grand-HF-T tweeter.

[JohnA]

Hmmmmm. Your ears must sound a lot like mine. Yours is about the same reaction I had when I first heard Jubilees in Hope. I did not think the ultra highs were harsh, but slightly muted. I generally liked that. We listened loud, too loud most of the time and they were WaaY bigger than life. I also thought they were boomy. A lot like many of ther ultra high end speakers I've heard (Infinity Reference Standard, Pipedreams). I wrote that off as a development deficiency since it was a prototype. I'm pretty sure those units had passive crossovers.

When you say K402, do you mean the horn, driver, or the combination? I built a 2-way system using an Altec 511B902-8B and a Peaver FH-1 bass horn. This setup sounds much like my La Scalas and I don't sense a loss of HF. The 902/511B is smooth and detailed. The 511B has some ringing problems, but like the K400, but most go away when I bolted it to a case. I can imagine a 511B (or better yet, a 1.4" 511C) made from glass reinforced polymer that wouldn't ring; it should sound superb.

[PrestonTom]

Greg,

Thank you for taking the time to do a detailed review. I do have a couple of questions.

1. You mentioned the Jubs sounded best in a larger room. What was the approx size of the two rooms in question?

2. It also sounds like you generally prefer a high end that is toned down. Do most speakers, strike you as being "too hot". I have known others with such a bias.

3. The active crossover you were using, was this a EV dx38 or was it the Crown XTI amps?

4. Perhaps in a separate thread you may want to comment on the Jamborees (their build and sound). Very little info is available about them.

Take care,

-Tom

[Marvel]

Greg,

Great post! Thanks for sharing your thoughts. It's certainly hard to convey what we each hear in our own locations and setups. I appreciate you trying to get across what you are hearing.

This really makes me wish I could hear Rigma's passives. His are a no holds barred version, and it would really be interesting to hear some that have been tuned a bit more. (Not to knock Dean's work... [] )

I was thinking some of it could be the amp, but Rigma uses some 300B amps on his, too. What a hobby.

Bruce

[greg928gts]

John - my K402's have the K69 drivers and that's what I'm referring to. I've edited my post.

Tom - my living room is 21 x 16 x 9' with beams 3' on center across the ceiling. No matter what speaker I have in there, I wish I could take half the crap out of the room, it would make the whole system sound better. No, speakers generally don't sound too hot to me, I would say that I hear the horn harshness or edginess that so many people talk about with horn loaded speakers in general. Generally I prefer the high-mids down a bit, and the high highs up a bit. I also prefer the low frequencies tipped up a bit. I own and have used both the dual crown amps and the EV DX38 with the Jubilees. I was genuinely disappointed with the sound from the crowns and pleasantly surprised by how good the EV is. I think the EV would be a great tool for designing passive crossovers.

Bruce - Dean told me it was an intermediate build on the passive networks. I agree that some tuning and/or higher quality parts would be fun to try. The choice of the 299A was for the Khorns for Karl to hear. I didn't want to use my 2A3 SET amps for Karl's first time hearing Khorns. The 2A3's are an acquired taste. The 299A is a sweet amp that works really well with Khorns and it gave me the option of nudging the bass for some of our listening. It turns out it's an awesome amp for Jubs too! (no bass nudging necessary)

Greg

[stereohermit]

what kind ofpassive HF eqingare you doingm if any. Love to see a schematic of your XO.

[greg928gts]

what kind ofpassive HF eqingare you doingm if any. Love to see a schematic of your XO.

The design is from Roy Delgado, Klipsch engineer. I've attached it to this post.

What is not shown in this schematic, is how much the signal is being manipulated.

Greg

KPTKHJKPT402K69A.pdf

[Guest " "]

I may have missed it in another thread.....are these OEM Klipsch Jub cabs or DIY versions?

[greg928gts]

I may have missed it in another thread.....are these OEM Klipsch Jub cabs or DIY versions?

OEM

Greg

[Arky]

Greg

How much smaller is your shop room? Hope the negotiated 2 wks didn't cost you too much.[]

[stereohermit]

Try running a 1.5 to 3 mf cap diectly from input + to HF driver+. This will give a 6 db/octave eq to the top. Leave the existing filter intact. Adjust the value of the cap, bigger lowers the hinge frequency. This is for 8 ohm driver, if 16 ohm, cut values in half.

[djk]

I think you would be better off to use a 2µF cap in series with a 40µH inductor and run that from the amplifier + to the HF +

This will bypass the attenuation of the HF above 8Khz, and not affect the rest.

[greg928gts]

Greg

How much smaller is your shop room? Hope the negotiated 2 wks didn't cost you too much.

12 x 14 - with one of the 14' side walls open about 2/3rds of the way to another space about the same size. It's a good Heresy, Cornwall, Acoustat One, AR-90 room, and it was also the room where it all came together in that mystical way one day with the split La Scalas with the bass bins turned backwards.

Greg

[colterphoto1]

I think generally passive networks can only cut frequencies.

Roy's eq curves clearly call for a shelving and high bump in the active network for proper HF section with the K69 driver.

No wonder you weren't happy with the top end.

Michael

[colterphoto1]

what kind ofpassive HF eqingare you doingm if any. Love to see a schematic of your XO.

The design is from Roy Delgado, Klipsch engineer. I've attached it to this post.

What is not shown in this schematic, is how much the signal is being manipulated.

Greg

See the bits in the network where there is a resisitor, cap, and choke in line ACROSS the +/- for each driver? That is a 'parametric' eq filter cut of a certain bandwidth of a certain depth of a certain 'Q' or width of frequencies, all determined by the choice of parts for that filter circuit.

If I'm reading the schematic correctly, the LF has a 24 db/octave low pass cutoff with a single PEQ filter. The HF section looks like 24 db/octave slope with the resistor padding down the circuit and two PEQ filter sets. EDIT, I stand corrected on my original read of of the network slopes [:$]

I'm sure one of you bright lads can correct me on this.

Michael

[stereohermit]

I'd say 24 db LF, 24db HF.

[colterphoto1]

Thanks Hermit, above post edited. Reading the network sideways, I missed entire sections.

[Chris A]

...Tom - my living room is 21 x 16 x 9' with beams 3' on center across the ceiling...Generally I prefer the high-mids down a bit, and the high highs up a bit. I also prefer the low frequencies tipped up a bit. I own and have used both the dual crown amps and the EV DX38 with the Jubilees. I was genuinely disappointed with the sound from the crowns and pleasantly surprised by how good the EV is. I think the EV would be a great tool for designing passive crossovers.

Bruce - Dean told me it was an intermediate build on the passive networks. I agree that some tuning and/or higher quality parts would be fun to try. The choice of the 299A was for the Khorns for Karl to hear..

I know that you have a strong bias against active crossovers, but I'd try Roy's EQ settings once again on actives in your now bigger room, biamping. (Actually, I find that the Jubes like an even larger room than the dimensions you related above.) I'd push the center of highest PEQ frequency up to about 13.5 KHz, increase the "Q", and boost the gain from Roy's setting about 1-2 dB (to taste). In addition, I would try a significantly different lf EQ than that published by Roy. It removes most of the boominess, and adds some more gain on the bottom end to add back a little for "expected room gain". I found these changes added a great deal for the older recordings that I own, etc.

I've got a different lf set of PEQs if you are game to try it again. Just let me know (email or PM) if you are interested, and I'll forward the curve to you. I'm guessing that the passive you are using doesn't handle those big 180 Hz and 97 Hz peaks, or the boost you'll enjoy on the bottom end (if you can believe it...).

Chris