K31 and the Jubilee

[PrestonTom]

I had a couple of questions about the K31 woofer and the Jubilee

The original Jubilee prototypes were said to contain K-31 woofers (the same woofer used in the KLF-30). I believe this was from a knowledgeable source(s).

1. My assumption is that this was also the woofer used on the Delgado & Klipsch article in JAES (the true original prototype). Any comment?

2. Although the K31 was used in the prototypes, was it also used in the commercial/theater version of the Jubilee?

The reason I ask this is that in the past there have been substitutions of drivers between the home and commercial versions. For example this was done with the K-33 vs the K-43 in the La Scala for instance. Obviously, some of the speaker's parameters will change with the "beefier" versions used for the higher wattage applications (again consider the K-33 vs the K43). Any comments?

3. The JAES article specifies the T/S parameters required but has anyone presented the actual T/S specs for the K-31? I am not sure if these are availabl. If they are propritary, I'll respect that issue and not pursue it

4. Is it still the consensus that the Pioneer 51D is the "closest match" for the T/S outlined in the JAES article? I know that JC suggested that the Pioneer 51F may have actually "sounded better" than the 51D (in spite of being a poorer match in terms of the numbers). However, at this point I am trying to "understand" the Jubilee in order to do some experiments, so the numbers are important.

Thanks,

-Tom

[Guest " "]

This was posted on the forum by a forum member who actually tested one.

Be advised, there is a k-31-e and a k-31-k. I'm told that the k-31-e is the one you want to use. Not sure why.

[jwc]

Tom.

Yes. I have that same info from an unknown source.

It is difficult to find a "quality" woofer with the spec like the K31. If you were to go through Partsexpress.com or USSpeaker.com...there isn't much the same as any pro woofer listed.

Non expert stuff coming...brace yourselves.

In the Non pro section of Partsexpress....there are the pioneer options and then there is one 12" Dayton woofer that is pretty close. The problem with these non pro woofers is there weak Xmax. The Pioneers weren't as punchy as the K31's but the 51F was a real grunter and probably has slight less SPL. The Dayton option would be about the same I would guess.

The Kappa Pro 12" worked somewhat as the Vb calculated close the same as the K31. I would guess the "annullment" would be closer. Big time punch. No grunt. If you were one to throw in a Subwoofer with the Jubs...these might be a good setup. Much louder too.

If you find a good pro woof as a substitute....love for someone to try it out.

jc

[colterphoto1]

a subwoofer with a 'jube'? - sacrilege.

not to discourage r&d, but what's the point?

[Coytee]

a subwoofer with a 'jube'? - sacrilege.

not to discourage r&d, but what's the point?

Clearly you have never experinced the suckatude of their bass...

[*-)]

[PrestonTom]

.....

not to discourage r&d, but what's the point?

Michael, perhaps your comment is directed toward me.

As I mentioned in an e-mail to Roy, the analogy is that of building a '67 Mustang vs hot rodding '67 Mustang. I am in no way taking away from their (Roy & PWK) accomplishment. However I do come from a generation of father-son projects of building Heathkit amps (and learning something on the way) and this has progressed to DIY projects of all sorts. As a DIYer with a technical background and a love of audio, this is a natural.

I do not expect to stumble in and do a better engineering job then an experienced engineer. I am not that presumptuous. However, to get up to speed I need to understand the Jubilee.

As with anything there is always room for improvement or customization. For instance there were various criteria listed in the JAES article. Some of these were constraints (e.g., no larger than the the footprint of the K-Horn, height, eliminating compound cuts). For my own use, I would re-prioritize these. There are also some other features I might like to include, but I am getting ahead of myself.

First, I am laying out a physical model of the cabinet (in 2-D) in order to get a better feel for the geometry and flare rates. It is interesting, although at this point I am probably simply rediscovering what others have already found.

Please indulge my curiosity,

-Tom

[colterphoto1]

oh, don't get me wrong- tweak to your hearts content.[Y]

I was just responding to the idea that a Jubilee needed additional bass support. Yes for any HT use a dedicated sub is always a good idea, but for normal 2 ch listening, I can't imagine a more gorgeous natural sounding bass than I have heard with the Jubilee.[]

Paul and Roy's variety that is. []

[Guest " "]

PrestonTom

Last weekend 4 k-31-k's new in a box where sighted off the coast in warm waters. They were initally offered to one forum member, but after some exchange of emails, were sold to a forum member whose time line for using them was in the short term.

If there are more sightings for new k-31-k's, do you want to be notified?

[PrestonTom]

PrestonTom

Last weekend 4 k-31-k's new in a box where sighted off the coast in warm waters. They were initally offered to one forum member, but after some exchange of emails, were sold to a forum member whose time line for using them was in the short term.

If there are more sightings for new k-31-k's, do you want to be notified?

SF, Thanks for thinking of me, but I will defer since I am still in the drawing and planning stages.

I still wondering about whether it is actually the K31 being used in the commercial cabinets (as opposed to some beefed up, heavy duty version). It is concievable that since the time when the JAES article (and the original prototypes) Klipsch Inc was able to procure or specify a better driver. This is just wild speculation and I was wondering if anyone actually knew.

By the way, where are you on your project. I saw some plans you posted (with some tricky cuts on the ramps), did things come to fruition?

Good Luck,

-Tom

[Guest " "]

PrestonTom

I have a modified deisgn which is still on the drawing board.

I have most of what I need.

Just a little more space needs to be freed up in my Garage shop.

There are two versions of the K-31 that I am aware of. A K-31-E amd a K-31-K.

[bodcaw boy]

I had a couple of questions about the K31 woofer and the Jubilee

The original Jubilee prototypes were said to contain K-31 woofers (the same woofer used in the KLF-30). I believe this was from a knowledgeable source(s).

1. My assumption is that this was also the woofer used on the Delgado & Klipsch article in JAES (the true original prototype). Any comment?

yes it is.

2. Although the K31 was used in the prototypes, was it also used in the commercial/theater version of the Jubilee?

yes it is.

The reason I ask this is that in the past there have been substitutions of drivers between the home and commercial versions. For example this was done with the K-33 vs the K-43 in the La Scala for instance. Obviously, some of the speaker's parameters will change with the "beefier" versions used for the higher wattage applications (again consider the K-33 vs the K43). Any comments?

3. The JAES article specifies the T/S parameters required but has anyone presented the actual T/S specs for the K-31? I am not sure if these are availabl. If they are propritary, I'll respect that issue and not pursue it

yes they are.

4. Is it still the consensus that the Pioneer 51D is the "closest match" for the T/S outlined in the JAES article? I know that JC suggested that the Pioneer 51F may have actually "sounded better" than the 51D (in spite of being a poorer match in terms of the numbers). However, at this point I am trying to "understand" the Jubilee in order to do some experiments, so the numbers are important.

Thanks,

-Tom

have a blessed night,

roy

[sunnysal]

well now that was easy and painless. but what about the 31e versus 31k question? Tony

[DrWho]

My guess would be that 31-E means it was built by Eminence and that 31-K means it was modified by Klipsch? Or built by some other company that the codename K stands for?

Does anyone know how low the squawker in the KLF-30's go? It might be a wild upgrade to throw a Jubilee bass bin under that squawker/tweeter combo. I believe the KLF-30 and Chorus II share the same tractrix squawker which I also believe shoud be capable of driving up to 20kHz with an appropriate driver...sorta like a mini 510?

[bodcaw boy]

well now that was easy and painless. but what about the 31e versus 31k question? Tony

hey tony,

how are you doing?

k-31-e is an eminence built woofer (current)

k-31-k is plye built woofer (klipsch used to own pyle)

both woofers almost identical since we own the tools for the pieces the woofers uses.

have a blessed day,

roy

[ZAKO]

Klipsch used to own Pyle? YUK !!!! No wonder the magnets always fell off.

[sunnysal]

HI Roy, Thanks for the clarification. Things are great down here in Sunny El Salvador, I have been so busy with work that I have not had much time for the hooby side of audio, just listening to great music on my system and enjoying the wife and kids...kinda healthy now that I thinkj about it. Hope you are well and happy too! Regards, Tony

[Duke Spinner]

Klipsch used to own Pyle? YUK !!!! No wonder the magnets always fell off.

+ 1 , Maron .....[+o(]

[babadono]

Resurrection from the dead???....

So I got a new Jube bass bin yesterday, well actually a set and the woofers are definitely wired in parallel according to the jumpers on the cabs. But the label says 8 ohms. Is this correct? Are there impedance curves for these babies?

@Chief bonehead@Chris A@mikebse2a3

Yea and pics later in another thread yada...yada..yada

[Chris A]

Well, I'd call it "8 ohms, nominal":

[mikebse2a3]

1 hour ago, babadono said:

Resurrection from the dead???....

So I got a new Jube bass bin yesterday, well actually a set and the woofers are definitely wired in parallel according to the jumpers on the cabs. But the label says 8 ohms. Is this correct? Are there impedance curves for these babies?

@Chief bonehead@Chris A@mikebse2a3

Yea and pics later in another thread yada...yada..yada

 

Like Chris stated 8 ohms nominal seems reasonable with a 4 ohm minimum rating.

 

If using tube amps I would suggest trying both 4 ohm and 8 ohm taps. The 4 ohm tap will give the best electrical damping and is what I have used but like much in sound reproduction there can be many variables in a reproduction system/listening room such that the 8 ohm tap might be preferred in some situations.

 

miketn