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Old Hereseys, general info?


mmmalmberg

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I have a pair of old Hereseys which have been living in the garage for a while, got them at an estate sale for less than $100.

These have cane grilles, a blond mahogany sort of looking veneer, and are in pretty nice shape. But they sound a bit droopy compared to what I imagine they should sound like.

Here's some info from them:

Model: H700 Heresey

Type: H-M2-12

Serial # 2G405

Inside, crossover type appears to be "C" but hard to read. It has a 2 uF 600V square can cap (WestCap) and another (Aerovox) which I can't read the value but it's rated 1000 VDC and is oozing some orange goop.

Woofer = K-22

Mid = K-55-V

Tweet = K-77

1/2" plywood backs.

They seem to lack a bit of punch at either end - the highs are muted and the bass is not particularly impactful. They don't sound bad, just not quite hi-fi. They sound lifeless next to a pair of KEF Coda-90's I have, for instance.

So, not being a Klipschionado (although I do also own a pair of their pro audio 12" 3-way PA speakers), are these worth pursuing? What would be obvious updates? I'm guessing the drivers are OK and maybe just finding some new caps might bring something back?

Anyone know how old they are?

Thanks much for any info and/or thoughts about these.

Mark M.

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Think that you are right that new caps on the crossovers would be helpful. Bob Crites (BEC) on this forum is a convenient source for them. Hearing you describe the sound, I sure wonder if the tweeter diaphragms are sound. If you can hear them they probably are, but would require putting one's ear close to confirm.

I'd think they should sound pretty similar to your pro audio Klipsch speakers, but haven't had the opportunity to hear them. Maybe someone could chime in on that.

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Thanks, all.

Dodger, if you mean the logos, it's the same on all drivers and on the grill, the old logo with the backward P, the PWK sitting over a big V. The woofer has a square magnet structure.

Daddy Dee, Does BEC provide some sort of NOS caps, or can one use Solens or other popular caps, or is it critical to use a particular new cap? I know there are discussions of cap replacements around this forum but I don't think I saw anything for this old a unit, but it was a while ago I originally looked.

They certainly don't sound anything like my Klipsch PA speakers, 'though they are the same size and format. Would be great if they could end up sounding more similar, that is for sure. I should probably disconnect the tweeters and see if it sounds any different...

Again, thanks for these and any forthcoming thoughts.

Mark M.

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The way I understand it, those Hersey's should have the 16ohm woofer which need to have the Type C network. In '72 or '73 they changed to using an 8ohm woofer and changed the network to a Type E. I'm guessing that the 16ohm woofer had an orange surround, the 8 ohm didin't.

In my 71 Hersey's, the woofer had been replaced with the newer 8 ohm woofer but the crossover was never updated. They sounded just like you described. At that point, I reworked my C network into an E network and they sounded great.

The C and the E were close, but the C used a different capacitor, different taps on the Ta2, and was wired differently.

In any event, it sounds like you need to rebuild those crossovers, oozing goo can't be good.

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Well, this is getting more interesting:) I have ordered caps from Bob to update the crossover to "E", as suggested. So now, the woofers... They don't have an impedance marked on them, just the number 4171 stamped onto the label. They do have an orangish cloth surround, and a stamped steel frame.

This will be intesting, if it turns out I'm wiring a 16-ohm woofer with the later network designed for 8 ohms. I've no idea what the result of that would be. Sure not looking to replace the woofers at this point.

I did put my ear to the tweeters and my belief is they are working, just muted. I guess I'll post my findings once I have rewired/rebuilt the networks. Perhaps I should first, however, resolve this issue with the woofer spec. Can the impedance be measured with DC, i.e. a vu meter?

Thanks one and all...

Mark M.

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Well I'm pretty sure those are the 16 ohm woofers if you have the orange surround and No, you don't want to replace those. Someone will have to chime in on whether you should update to the E. I would say no, just rebuild the crossover as a C. I don't think anybody has a C schematic, but I made notes on mine that I can dig out if needed. The C used a 2uf cap and a 1uf cap, the E used two 2uf caps.

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----------------

On 1/26/2005 8:54:22 PM mmmalmberg wrote:

Well the DC resistance of the woofer voice coil is in the neighborhood of 6.5 ohms. So perhaps these are the 8-ohm woofers and just as suggested need the later xover in which case I'm feeling good... hope so.

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Assuming you measure the driver disconnected from the x-over... sounds like the 8ohm variety. Don't be shy and ask Bob about the switch... he is quite helpful.

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On 1/26/2005 9:25:08 PM scott0527 wrote:

Well I'm pretty sure those are the 16 ohm woofers if you have the orange surround and No, you don't want to replace those. Someone will have to chime in on whether you should update to the E. I would say no, just rebuild the crossover as a C. I don't think anybody has a C schematic, but I made notes on mine that I can dig out if needed. The C used a 2uf cap and a 1uf cap, the E used two 2uf caps.

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My understanding is recone kits were offered with either the orange or black surrounds, in either 8ohm or 16 ohms. I have a pair of 8ohm Alnico K22 with the orange reconed surronds... as well as some with black surronds.

Later...

Rob

PS: It's my opinion that the Heresys are pretty bass SHY by design... they aren't a Klipschorn 2.gif

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I don't have a schematic of the Type C crossover, but I think the woofer circuit in the C and E may be identical with just a 2.5 mH inductor. Also, you may want to note that the Klipsch schematic for the Type E crossover states at the woofer output: K-33-E 11 ohms.

Bob

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I don't know the value of the inductor in the "C", which is marked 2133. Comparing to the Type E diagram, the woofer wiring is identical.

It appears to me, if I'm not crazy, that the woofer is out of phase with the squawker and tweeter in the Type E configuration, and in phase in the C configuration.

Bob I've done a sketch of the C schematic which I can email to you (or anyone...) if you're interested. The tweeter goes to the #2 tap through a 2.1uF cap. The squawker is going to tap #1, and the woofer goes through the inductor and a 1uF cap to tap #5.

So in any case I'm figuring the woofer's probably not a problem, although I don't know if there's a correlation between the woofer impedance and the selection of cap values - ?

Should I drive these units off the 16 ohm output of my amp?

Why would the phasing be different between these two crossovers?

thanks...

Mark M.

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"It appears to me, if I'm not crazy, that the woofer is out of phase with the squawker and tweeter in the Type E configuration, and in phase in the C configuration."

Reversing the squaker leads was a positive change made by Klipsch in the early seventies and continued. A bulletin was sent to Klipsch dealers to rewire all their stock with the reversed connections. Information about this can be found in the "Dope From Hope" papers.

Rick

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Well that seals the deal on woofer confusion, I'm sure I'd need to measure to know for sure at this point.

I'll probably go one step at a time, get some new caps in there, test with different wirings of the crossover and see where that gets me, based on sound.. Clearly given the differences between the C and E networks there's some room to play.

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