Vintage speaker small box syndrome?

I have a pair of Kenwood KL-777 speakers. They have 15 woofer, dual 5 in mids, and dual hornish looking tweeters plus one ultra high tweeter per speaker. Gotta love the more was better back in the days.
I really like the sound of these speakers. They have very fat bass and huge mid which helps my V-shape hearing frequency response. The tweeters are not very good due to very narrow dispersion pattern.
Anyways, they are sealed speakers and the boxes seem like kinda small for how big the woofers are.
I wonder if I could make bigger boxes for better low frequency extension also allows me to use modern tweeters?

The Sansui, Kenwood and other speakers of the era these came from all emulated the more furniture-like appearance of a Barzilay or McIntosh speaker - they were knock-offs!

The fact that all of the front panel was covered with drivers indicates that these were built to be marketed to the returning GI of the 70s (from overseas duty) in the late 60s and early 70s. How do I know? I went to school with the guys who came back with the gear!

As far as re-engineering them with larger cabinets, sure you can do that. I'd suggest, though, that they're likely worth more to collectors in original form. You might, instead, consider building some speaker kits from places like Parts Express or Madisound. There are others, of course, but those come to mind first.

The build quality and design technology of drivers these days far surpasses anything of the vintage of the Kenwoods you have.

Cheers,

David

Yeah The boxes of a lot of vintage speakers are often too small it seems for woofer size, except some of the better ones . They might still sound good though despite too big of a woofer.

Hey mang,

I hope this doesn't turn into another thread for bashing, let's cross our fangers.

I'm another one for keeping them the way they are. Especially if the enclosures are more than serviceable, it'd be a shame to gut'em. If you were to find another pair with mashed ones, good drivers, then I'd say tear it up and see what you can come up with.

I've got 4 Sansui SP-3500's in my living room jacked into a Sansui quad receiver. The word on the street is that they too suffer from the too small enclosure and can't go low enough for many. I would agree that they aren't an every day speaker that will handle all genres. However, when you put some bluegrass, vocals, midrangy music through them? The hairs on your head will stand up tall. They give me the shivers, in a good way. For what I paid, for what many pay for them, they're an outstanding value.

The first thing that you absolutely must do, is replace the capacitors in the network. They're probably more than 35 years old and weren't all that great when new. I'd be willing to bet you a burrito and a Mexican Coke that those tweeters and mids will open up on you like a fresh ocean breeze with new caps. Unless you've already replaced them, then nevermind.

xo, Biggles

To answer the question: generally a woofer in too small a sealed box will roll off pretty high and often have a boomy peak just before rolloff. So a bigger box <might> improve performance.

I'm thinking that your not liking the tweeters HF may have much more to do with tweeter in general, regardless of "dispersion pattern" narrow or otherwise.

Just a guess.

RC

Thanks for all of you guys suggested.
I kinda agree with some of the people says about just keep these as they are.
For $75 bucks I paid, they are in pretty good condition. Probably not as good as Sansui ones but they are way better than most of the entry level modern speakers.
As for the tweeters, the optimum listening location is very narrow. You move side to side and one side would lose it's high frequency.
I might recap the crossover when I find time.
I wonder how much work is there to build my own speakers. I guess designing the crossover is gonna be the hardest part.

I don't think moving these to a larger cab would be much of an improvement. Definitely not one that would make it worth the effort. Low bass extension was not even a topic for the music of the era these were designed for. Heavy bass, sure but not the low deep bass we've become accustomed to with modern sub-woofers and all. drbiggles suggestion to replace the capacitors makes the most sense. A clear high end will make the whole speaker sound fuller.

jasonsong86 said:

...Anyways, they are sealed speakers and the boxes seem like kinda small for how big the woofers are.
I wonder if I could make bigger boxes for better low frequency extension...[/IMG]

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I would keep the boxes and build an extension onto the back, or make fake stands/risers that attach to the bottom. You cut a huge hole in the bottom of the cabinet and seal the riser to it, effectively increasing the cabinet volume. The tweeters? It may actually be a crossover issue, as I've seen bad caps destroy a tweeter's sound quality... it could affect dispersion in theory (if the improper frequencies aren't even making it to the driver, it could sound like the dispersion has decreased), and caps are cheaper than completely new drivers. Try new caps first, then try new drivers.

As for the poor dispersion of the speakers I wonder if I place them horizontally (tweeters vertically), would it make the shitty dispersion get better?

So, lemme see if I have this right. You want a speaker with a nice, fat upper-bass response and rich, pronounced mids (to help with your scooped hearing range), and clear, nicely-imaging highs, right?

Sounds like a Pioneer HPM situation to me.

Gang-Twanger said:

So, lemme see if I have this right. You want a speaker with a nice, fat upper-bass response and rich, pronounced mids (to help with your scooped hearing range), and clear, nicely-imaging highs, right?

Sounds like a Pioneer HPM situation to me.

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There is a guy selling a pair of 700 for $300 and 100 for $900. I think these prices are outrageous.

The time, money and effort you might put into these would not offer a monetary return, and may well do the opposite. Also, sonic value for the change is also iffy. There is not much upside to the butchery contemplated. I very much agree with those who recommend starting a diy from scratch, and if you don't like the vintage speakers you have then sell them to help fund your new project. If you like the idea of using old cabinets, then you can find them cheap with missing or damaged drivers, but the ones you have seem to be in very good condition and worth conserving for posterity.

jasonsong86 said:

As for the poor dispersion of the speakers I wonder if I place them horizontally (tweeters vertically), would it make the shitty dispersion get better?

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Probably would. Any horizontally mounted pair of drivers is going to have a narrow horizontal dispersion pattern, but better vertical dispersion due to cancellation effects.

The first thing I would try is disconnecting one of each of the tweets, (and mids!) to see if the dispersion at least improved. Removing one load from the crossover may substantially change the crossover frequency though, unless the designer used two identical filters for each one of the pair, which is unlikely given the added cost.

Maybe just block one tweeter to see what that sounds like.

Right, if in series, the ohms change when disconnecting one of the speakers.

I'm a bit surprised that they are sealed boxes. Typically 12" woofers are about max size for an acoustic suspension design. Since they are sealed, pull one of the woofers and see how much fiberglass stuffing is in them. It may be that adding more stuffing would help the bass response. And as already stated recap the crossovers. That should really help out especially mid and HF's. I added a sub in with a set of Sui SP-2500's. That was the fix that was needed for them to sound very good.