Updating Heresy Speakers

[KDNoyes]

Could someone tell me what would be available to upgrade a pair of Heresy I speakers, purchased in 1983 new. Still have them, still love them. Or do I just leave them alone. Thank you.

[Groomlakearea51]

Welcome to the Forum. Many things can be done....

First....

• Replace the caps
• Unscrew the woofer and turn it 180 degrees.
• Seal the back with speaker gasket tape.

Second, at some point....

• Either replace the tweeter diaphragms, or replace the tweeters with Bob Crites (BEC on this Forum) CT-125's
• (NOTE: Late model 83's have the K-701/K53 midrange horn/driver; if that applies to your pair, consider replacing the midrange driver diaphragm with new ones also)

Third..... and maybe at some point.....

• Consider replacing the old worn out woofer (K-22 or especially if it's a K-24) with new K-28's from Klipsch Parts (used in the Heresy-III's), or Crites' CW-1228.
• Finally, consider refinishing, replacing grill cloth, etc.

See the below threads for details on working with Heresy's

http://forums.klipsch.com/forums/t/103886.aspx for serial, driver, finish data on the Heritage series

http://forums.klipsch.com/forums/t/109693.aspx for complete refinishing instructions

http://forums.klipsch.com/forums/t/110684.aspx for how to replace your grill cloth

Hope that is of some assistance.

[H]

[radiogram]

Replacing the tweeter with CT125 with the stock crossover is to be approached with some caution as it is technically not a direct drop in replacement for the Hersey and due its consequent end result. A "drop in" replacement driver by definition is one that has to satisfy the following criteria:

1. Same sensitivity

2. Once dropped in and integrated to the given crossover, its net acoustic response output shall have quite similar (if not exactly the same) acoustic bandwidth and roll of rates as the one it replaces.

While the CT125 is a good tweeter in some absolute sense, it is a mismatch with the Hersey or any heritage speakers that employ K77 with a 1^st order filter and a squawker section that is just high pass and not bandpass, like TypeA and some Conrwalls.

These networks in a sense "sort of" get away with it due to the natural roll off of the K77 below 4000Hz. Replacing it with any tweeter that has an extended response below 4000Hz to as low as 2000Hz will end up with exaggerated lower treble overlapping with the squawker’s full passband.

And given that the CT125 has sensitivity that is lower anywhere from 3db - 5dB, what you may get is relatively muted output above 5000Hz and exaggerated output in the lower range. Now one may be able to match the sensitivity by moving it up the T2A tap, while this will restore the high freq balance it is going to accentuate the lower freq overlap even more.

Forget all the technical stuff, I compared the K77 in my Hersey tweeter network, with the CT125 by listening to the tweeter alone disconnecting the woofer and the squawker and played a Bob Seger CD. With the K77 I could barely hear his voice, but with the CT125 his voice was well audible and clear. This part of the spectrum is already in the full passband of the squawker reproduced at full 0dB. So what you have is a different sonic signature from the original. Now one may like that is an entirely different story, but I would hardly call this transparent driver swap. Transparent by definition means one should not notice the swap.

The words “drop in” replacement by definition implies that when the replacement driver is mated with the given network its acoustic passband corners and roll off rates are very similar (if not exact) to the original. Within the passband it may have different performance aspects (distortion, different dips or peaks, smoother response, etc) that may lead one to choose over another. Nevertheless to be a drop in (meaning no change to crossover) it has to have similar passband corners and roll off rates and of course same sensitivity.

If one likes the sound subjectively I have no argument for that, but objectively it is not correct unless the crossover is steep enough to mitigate this by providing enough attenuation as to making it audibly not much perceptible or the squawker network is modified to be band pass with appropriate high frequency limit and slopes.

Having said these, I think the CT125 may be better suited with speakers using higher order tweeter sections like the TypeAA, Type AK3 and higher, with the following caveats:

1. There is still a lower sensitivity matching issue to deal with

2. The CT125’s sonic signature is very different from the K77, where its lower tones seem to dominate the higher tones, which whether you will like or not only you can be the judge.

[radiogram]

Deleted.

[radiogram]

I would first suggest replacing the Stock Caps with Audiocap Theta (from my experience) or Auricap (from others' experience). In addition if your Hersey is the same as what I have (K22, K53/K701, K77, E2 Network), then I will have some additional suggesstions.

[Ironsave]

Bob Crites sells a Sonicap kit on Ebay. He is a prominent member here who know his shit!

I replaced my original caps with these and it made a nice difference. (Around $50).

Bob is top notch and I trust his reccomendations regarding tweeter replacement; etc over other info.

Grooms links are very informative, and he knows his Heresies as well!

I also did seal the backs with foam sealing tape. (More bass). They now thump nicely, though I use my sub more often than not.

I think starting with the caps will make the biggest difference. (And while you are in there, you can seal the backs and rotate woofers if you desire).

Good Luck!

[KDNoyes]

Thank you very much. I'm overwhelmed with the information that you guys can provide. This is great. I read that you also use a subwoofer. Do you have Heresies hooked up to a surround sound amplifier? Because that's a predicament, how to go forward with say 5.1 and keep the Heresies.

thanks much for the help

[Ironsave]

Thank you very much. I'm overwhelmed with the information that you guys can provide. This is great. I read that you also use a subwoofer. Do you have Heresies hooked up to a surround sound amplifier? Because that's a predicament, how to go forward with say 5.1 and keep the Heresies.

thanks much for the help

You can see my system in my signature.

I live in an apartment..... If you have enough room, there are members who have 5 Heresies set up +1 sub.

I do use a 7.1 receiver (5.1 for now till the KG3s are done). I listen to music set to 2 channel + a sub.

Lately (since I got the KV-4) I have also been using Neo 6 Music and Prologic II Music decoders with really nice results.

So for movies or TV; I just switch to a different decoder (I like Enhance or Neo6 Cinema)......

So.... it can be done.

Others will set up a dedicated 2 channel setup in a preferred music listening area and then use a seperate 5.1/7.1 system strictly for HT.This is my goal someday, but not possible in a 900 sq foot apartment.

Hope that helps...

[SilverSport]

I have three Heresys across the front for HomeTheater and the sound is wonderful...I updated the crossovers (Bob Crites did the work, I just installed) and I replaced the Tweeters withhis CT-125 as the Center Heresy I had ought already had it...I have had Heresys as rear surrounds but replaced them with KSP-S6s for size considerations (...and I thought I was wasting the Heresys back there)

Bill

[KDNoyes]

Thanks Bill,

I'm guessing you're driving those with a 5.1 receiver of some kind??

[psg]

Replacing the tweeter with CT125 with the stock crossver is a very bad idea and clearly technically very wrong. One needs to understand clearly that a replacement driver is one that has the same electrical response characteristics as the one it replaces given a certain crossover network. While the CT125 is a good tweeter in some absolute sense, it is a mismatch with the Hersey or any heritage Klipsch for that matter with the stock crossovers. All Heritage netwroks are not only low order networks, in addition they also depend on the natural rapid roll off of the K77 below 4000Hz (and thus depend on the natural high roll off of the squawker driver without imposing any high freq limit to it like by using a band pass for the squawker). Replacing it with any tweeter that has an exteneded response below 4000Hz to as low as 2500Hz is absolutely wrong. CT125 is not only lower in sensitivity compared to K77, in addition one will end up with exagearrted lower treble (2500 - 4000 Hz) overlapping with the squawker (K53 goes well upto to 6KHz).

So, what you get is relatively muted output above 5000Hz and exagrereated output in the 2500 - 4500 Hzz range. Many people claim they get more details and crispness with this replacement. This is not true detail or crispness but only exagerrated lower treble and technically wrong. If one likes this sound subjectively I have no argumet for that, but objectively it is all wrong unless the crossover in the Squwaker-tweeter area is extereme slope like ALK networks or the crossover for the squawker is modified to be band pass moving the high frequency limit significantly lower.

I was under the impression that the AA and A networks (La Scala and KHorn) were high-pass for the tweeter signal, and thus that the CT-125 was a drop-in replacement in those speakers.

[radiogram]

psg:

I was under the impression that the AA and A networks (La Scala and KHorn) were high-pass for the tweeter signal, and thus that the CT-125 was a drop-in replacement in those speakers

I am sorry that I do not undertand your question clearly. While I do not have personal experience with either AA/AA, they are not just high pass tweeter netwroks. Both are balancing networks with a Low pass woofer section, squawker section tweeter section. In fact all Klipch networks are full dividing networks.

Also, AA/A networks are for Khorn/LaScala and have nothing to do with Herseys. If you can explain me more your question, I can answer better.

Cheers

[psg]

psg:

I was under the impression that the AA and A networks (La Scala and KHorn) were high-pass for the tweeter signal, and thus that the CT-125 was a drop-in replacement in those speakers

I am sorry that I do not undertand your question clearly. While I do not have personal experience with either AA/AA, they are not just high pass tweeter netwroks. Both are balancing networks with a Low pass woofer section, squawker section tweeter section. In fact all Klipch networks are full dividing networks.

Also, AA/A networks are for Khorn/LaScala and have nothing to do with Herseys. If you can explain me more your question, I can answer better.

Cheers

I am bringing up the LS and KHorn because you said or any heritage Klipsch for that matter. AFAIK, the AA network is high-pass for both the tweeter and mid sections, i.e. it is not band-pass for the mid and assumes that the mid simply isn't outputting any sound for the frequencies also fed to the tweeter. The high-pass frequency for the tweeter doesn't depend on the tweeter's low-end drop-off and so a CT-125 can be swapped in.

[Groomlakearea51]

The CT-125 is a "drop-in" replacement for the K-77. Specs are very similar and while I will support radiogram's observation about the 4500 type crossover being particularly suited for CT-125 applications (it takes advantage of the wide response curve), but.... it will work transparently with the other crossovers in the Heritage series. I now use the CT-125 in almost all my Heritage series (see profile), and with outstanding results. I do use the A/4500's on the K'horns in the "man cave", and on the Belles in the living room; Notably, all of my Heresy's are E/4500's with CT-125's, either K-55's/700; or on 2 pairs, D250X's with the tap dropped down one to compensate for the 250's high sensitivity; and either K-28' or CW-1228 woofers. I have done extensive A/B testing, with alot of folks who have visited my home and all can attest to the sound from the CT-125's.

Just my humble opinion based on 35+ years of owning a boat load of Heritage series (still do...) and pretty much listening to them (and rebuilding & restoring etc.,) every day.

[radiogram]

psg:

Ok. This warrants a corrective statement from me. I have rephrased and corrected my post accordingly. So please read the same again

The typeA falls into the said category. Its tweeter section is same as Hersey being first order. The squawker network except for the low cutoff being different is the same otherwise in that it is not a bandpass, thus allowing the full electrical output to be presented to it all the way to 20Hz. Even though the first order tweeter network only provides say a limited –xdB attenuation, the acoustic output of the K77 is actually much lower than –xdB, because the K77 itself acoustically drops off below 4000Hz (it is more than 10dB down at 3000Hz, all by itself fed with 0dB signal).

Now if one were plug in directly a tweeter which extends much below in frequency into the same network, then its acoustic output will be attenuated only by –xdB imposed by the network and not lower since say at 3000Hz it is within the full passband of the tweeter. So in comparison there will be more overlap now.

There is another aspect with TypeA is that there is no more room for higher sensitivity tapping as the tweeter section is connected directly to the input Cap. So there is no way to compensate for the lower sensitivity of the CT125 other the having to lower the sensitivity of the squawker and tweeter. My CT125s are about 6dB lower than K77, Greg of Volit Audio has reported 5.4dB lower and ALK also sometime back reported lower sensitivity.

Now, getting to TypeAA - It is not in the same category as above. While its squawker section is still high pass and not bandpass, it has a 3^rd order tweeter filter. This higher rate of attenuation should mitigate the CT125’s extended lower freq acoustic output. While it will still be more than the K77 in absolute terms, it may be at levels where it may not be audibly noticeable.

So, in that context for TypeAA sure CT125 is a good possibility. However again note the sensitivity issue. In the TypeAA also (like the typeA) there is no more room for higher sensitivity tapping as the tweeter section is connected directly to the input Cap. One will be forced to lower the sensitivity of the woofer and squawker which is a more complicated affair and further negates the higher sensitivity advantage of the Khorn or Lascala.

There are many tweeter choices out there (Beyma, Jbl, Selenium, etc). It is important one understands how they differ electro-acoustically form the one it replaces, does it need crossover mods and if so what changes and if one does not want to get into crossover mod at least understand what effect is.

I would categorize CT125 as an alternative choice like many others, rather than a direct drop in. At the minimum even if one had a steep slope network, crossover mod is required for sensitivity difference alone.

Again all said and done, one may like the end result subjectively, for which I have no argument. I can only give some perspective based on some objective aspects when in my experience it also somewhat seems to correlate with my perceived hearing.

BTW, Thanks for helping me to correct myself.

Regards

[psg]

Okay, thanks!

[JohnA]

Just to throw a kink in the works,if you have use the speakers regularly, the caps may not need replaqcement.

Two tests, use FM radio hiss and a sound meter to see if the output of one of the horns is significantly less than the woofers (>3 dB), or the 2 speakers don't match. OR, ..... Have someone not familar with the speakers listen to see if they sound dull. If they are not dull sounding or the squawker and tweeters are loudeer than the woofer, the caps are normal.

[spamer]

Hi,

I just purchased my first pair of Klipsch Heresy's, 1978 Decorator's.

You mention replacing the diaphragm's. I see that Crite's says that he is

out of stock of diaphragm's for the K-77's, indefinitely. Has anyone tried these

from a vendor on E-Bay? Seller is midwestspeaker.

http://cgi.ebay.com/Klipsch-Tweeter-Aftermarket-Diaphragm-K77-K-77-K-77M-/160460052032?pt=LH_DefaultDomain_0&hash=item255c2a1640

So far (3 weeks) I really, really like the Heresy's, they are definitely an upgrade from my Dynaco A25's and

sound great with my diytube ST-35. The one thing that bothers me is that the top end

gets too pronounced as I turn it up. I am hoping that some of your mods will help tone them down.

Thanks

Steve

[Islander]

So what you have is a different sonic signature from the original. Now one may like that is an entirely different story, but I would hardly call this transparent driver swap. Transparent by definition means one should not notice the swap.

The words “drop in” replacement by definition implies that when the replacement driver is mated with the given network its acoustic passband corners and roll off rates are very similar (if not exact) to the original. Within the passband it may have different performance aspects (distortion, different dips or peaks, smoother response, etc) that may lead one to choose over another. Nevertheless to be a drop in (meaning no change to crossover) it has to have similar passband corners and roll off rates and of course same sensitivity.

If one likes the sound subjectively I have no argument for that, but objectively it is not correct unless the crossover is steep enough to mitigate this by providing enough attenuation as to making it audibly not much perceptible or the squawker network is modified to be band pass with appropriate high frequency limit and slopes.

radiogram, you have a very narrow interpretation of the term "drop-in". Most members here take it to mean that the tweeter will physically fit and will sound good with no other changes being made to the speaker, not that it will be "stock-for-stock" in both size and sound.

When one is looking for an improvement, installing a tweeter that sounds exactly like the one you just removed will not give you that improvement. No-one claims that the CT125 tweeter sounds exactly like the K-77. To most people's ears, it sounds much better, and not just in the midrange. Cymbals sound noticeably more realistic, and they're definitely in the upper treble.

As well, the difference in output between the two new CT125s that I installed was less than 1dB, while the old K-77s that I took out differed from each other by 2-3dB, which did not help the stereo imaging. I didn't realized there was a problem until I heard the La Scalas with the new tweeters.

BTW, these are 1974 La Scalas with AA crossovers and fresh Sonicap capacitors, although they've since had the 510 JubScala conversion, so they're now 2-way with the 510 Jubilee tweeters.

[radiogram]

Islander:

radiogram, you have a very narrow interpretation of the term "drop-in". Most members here take it to mean that the tweeter will physically fit and will sound good with no other changes being made to the speaker, not that it will be "stock-for-stock" in both size and sound

I totally disagree. Just beacuse a tweeter is a physical Drop In has absolutely no bearing on how it matches with your existing speaker & network. Certainly subjectively one couls find it an improvement, but if subjectivity is the thing, then any one can drop in virtaully ANYTHING that physically fits can claim improvement.

My post was based on objectivity not subjectivity. One could use an equalizer or a tube amp with high output impedence and find the altered response better. The point here is when we say Drop-In it has to have some objective basis and CANNOT be based on subjective impressions. One's subjective opinion is as good as another.

No credible equipment manufacturer blindly builds things on subjective hearing including Klipsch. They may use it to tweak the end result but the foundation is still solid objectivity. Objectively the CT125 is a mismatch with first order networks that have squakers extending up to 6KHz. Just beacause one likes its overlapped sound cannot not in anyway make my analysis wrong.