Heresy speaker balance question

[jfmacken]

There seems to be a lot of topics covering the attenuation of heresy I tweeters, and their midrange drivers as well. Are they both 3db above the woofer in their stock positions? Are any modifications to the crossover absolutely necessary if one were to take both of these drivers down one tab on the autotransformer, or for two tabs? What I mean by this is, are there any significant changes that would change the quality of sound for better or worse (besides attenuation). Just curious:)

[dbflash]

This has been around for awhile.

I have never tried this and only works on Type E xovers.

Background: I have been enjoying Klipsch speakers since I heard my first pair of K-horns back in the 70's (instant addiction). However, until a year ago I had only had experience with the large Heritage Klipsch speakers and had never owned or listened to a pair of Heresys, so I bought a pair off Ebay.

They are 1980 Heresy I's with a K22-E woofer, K55-V squawker, K77-M tweeter, and a Type E balancing network.

I have owned and been listening to a pair of Cornwall I's (100% stock) for years and I am in love with the sound - I expected the same for my Heresy's. However, when I heard the Heresys, I didn't want to admit it, but they were just too bright and sounded to me nothing like the K-horns, Cornwalls, or La Scalas (lots of listening experience with each). The Heresy tweeters were just screaming loud compared to the squawker. In my Cornwalls, the tweeter plays at about the same level as the squawker when you put your ear by each one. This is also true of the K-horns and the La Scalas. I was contemplating getting rid of them and dismissing them as "not real Klipsch speakers." This sentiment was coming from one die-hard Klipsch fan too. My feeling was that the Herseys sounded decent, but not great. With all the Heresy modification posts here, I assume there are many who feel like I do.

Anyway, enough background, on to the good stuff, read: solution. After careful listening, I decided that the problem was definitely a tweeter problem, not a squawker problem, no need for a P-trap, or some caulking dope. After a quick search, I found a schematic for the Type E network on this BB and copied it down (search T2A, then read "The great inductor face-off"). The T2a transformer provides the attenuation for both the squawker and the tweeter. Each tap (six of them in all) is a 3dB increment. Note: the tap #'s on this BB's schematic is hard to read, the numbers should be 0,1,2,3,4,5 for the bottom tap to the top tap.

Anyway I figured "Hey why don't I just change the attenuation by trying different taps?" So I opened up a Heresy and unsoldered the wire from the #3 tap on the T2A (which goes through a 2uF cap then on to the negative terminal of the tweeter on the crossover). And here's what I found. (A copy of the schematic will greatly help you follow what's going on, even though it's quite simple.) Also, the #'s of the taps is written right on the T2A, so there is really no chance of making a mistake.

1. First I tried tap #4, which is unused. This brightened the tweeter up a lot (by 3dB, I guess). No dice.

2. Next, I tried tap #1, which is also unused. Dramatic attenuation of the tweeter, however, 6dB was too much attenuation. By the way, I'm using alligator leads for the tests. Also, I'm doing A/B comparisons with my vintage Alnico Cornwall I's for reference.

3. Finally I tried tap #2 which is the same tap used by the squawker's negative lead (so basically I just loosened the screw on the negative terminal of the squawker on the crossover, put the bare wire under it, and tightened the screw - piece of cake). This lowered the output of the tweeter by 3dB and was perfect! The voicing of these Heresys now very closely match the sound of my Cornwalls and other big Klipsch (less some low bass) and I must say I am thrilled with the results. These speakers now sound like "real Klipsch" to me. The Heresys also sound way better loud than they used to - they sound more like a big speaker. The bass and midrange are greatly improved because they are not being drowned out by the overzealous tweeter. My goodness, now THESE speakers have beautiful midrange too! Hail Klipsch!

I hate modifying anything from the original, but this was an exception. The results from this are also very apparent, none of that "deepened the sound stage" or "fuller bouquet" stuff - we're talking real results. Somebody else please try this modification and write back to this BB and post your opinion/findings.

Couple other things. 1) this modification is easy, FREE, and 100% reversible. I printed my modification on a piece of masking tape and taped it to the T2A for future reference (Although I'll never change it back, unless deep shag rugs come back in style and rob 3dB of my highs). You may or not like the mod as much as I do, but it sure is an easy way to change the tweeter attenuation, in both directions. Another benefit is that with 3dB of attenuation, you cut 1/2 of the power going to the tweeter (but with only a perceptable difference in loudness) thus protecting it from burnout.

One last point. I also tried stuffing one cabinet loosely with some damping material and compared it to the other speaker. The damping material definitely robbed some punchyness from the woofer and, in my opinion, was not an improvement - I removed it instantly. Also, any thoughts on my modification would be appreciated - I haven't read of anybody trying this, have you?

Hope this gives you some idea's.

Danny

[jfmacken]

I have tried cutting the midrange down, in addition to the tweeter, and found the results to be unsatisfactory. I'm not quite sure what the perfect balance point for heresy I is, but the tweeter is certainly too loud. Also, I find the K-55 midrange to be a much better sounding speaker than the K-77 tweeter in general, so it's nice to have the midrange stick out a little more:) So far I haven't done any experiments with damping, but I think heresy's sound great so long as you take that tweeter down 3db.

[fromnowon]

The 3rd point in post #2 of this thread seems very interesting - simply attenuate the tweeter this way.  I wonder if doing this could have any adverse consequences relative to crossover frequency or impedance load.  It didn't get a lot of discussion back in 2004!  I'm curious if anybody else has tried it and how they liked the change.  

This lowered the output of the tweeter by 3dB and was perfect! The voicing of these Heresys now very closely match the sound of my Cornwalls and other big Klipsch (less some low bass) and I must say I am thrilled with the results. These speakers now sound like "real Klipsch" to me.

.  

[SilverSport]

Hopefully someone else will chime in here but I thought something along the lines of Klipsch had already incorporated this change to their later Heresys by the late 1970s...

 

Bill

[Marvel]

Are any modifications to the crossover absolutely necessary if one were to take both of these drivers down one tab on the autotransformer, or for two tabs? What I mean by this is, are there any significant changes that would change the quality of sound for better or worse (besides attenuation). Just curious:)

 

Just moving the connections to different tabs would shift the crossover points. If you go to the following thread and read post # 35 by John Albright, and post #46 by Deang, you will find what came out of John Albright's mod and Dean's explanation. You can read the whole thing, too, for more background info, and Gil explains how autoformers work. Also, the mid and tweeter are much hotter in the original Heresy, and really intended to be placed on a wall or corner boundary, to help with the bass.

 

https://community.klipsch.com/index.php?/topic/21969-heresy-crossover-mod-less-bright/page-2

 

Some of this will also depend on how loud you listen. Since the bass is a bit weaker to most, when they get cranked up (over 85-90db+) the bass comes up due to the fletcher-munson curve. So does the treble then, too, which with a K-77 tweeter can be pretty annoying. The single 11 ohm resistor mod and moving the tap will greatly smooth out the tonal balance, and stay a bit more constant over a fairly wide range of volumes.

 

Bruce

[Pio]

https://community.klipsch.com/index.php?/topic/119380-heresy-hbr-i-xover-smoothing-modification/

 

link to mod pdf:

 

https://community.klipsch.com/index.php?app=core&module=attach&section=attach&attach_id=59142

 

very similar to John Albright's mod but for e-2 version, i think can be used with "e" version too, i like more DrTube version because uses a cheap (smaller) capacitor and retains too all the originals parts. no need to move taps,  i think worth a try.

 

by the way, this mod sounds very, very good.

 

 

best regards

 

Pio

Edited May 26, 2016 by yo0

[fromnowon]

Thanks very much!!  Post #35 in the linked thread does look like a very good, well-thought-out solution. I'd like to try that one.  

I really appreciate all the knowledge on this forum.

 

I wanted to get the resistor and capacitors for this at Parts Express, but having some trouble - 

 

Parts Express has this resistor but it's rated 10 Watts (not 20 as indicated in John Albright's mod).  http://www.parts-express.com/11-ohm-10w-resistor-wire-wound-5-tolerance--016-11    My amps are 35 watts and around 70 watts.

 

I also can't find a 21 uF cap at P.E., but they do have a 20uF 250V one:  http://www.parts-express.com/dayton-audio-dmpc-20-20uf-250v-polypropylene-capacitor--027-436

 

Are those close enough or is it critical to get the exact values?

 

Also, I wonder if the resistor is strapped across 0 and 5 directly on the side of the autoformer.  I can't seem to find a picture of the mod done on an actual cross over.  I suppose I could install the resistor between the leads that attach to 0 and 5, instead of across those taps directly.  

 

Thanks again for all the help.

[Marvel]

Directly across the terminals 0-5.

 

Bruce

[fromnowon]

Thanks Bruce (and Pio).  That helps a lot to see an example.  

 

P.E. tells me that 027-436 20uF is close enough to 21uF to work in this mod, and that 016-11 is ok to use at 10 watts (instead of 20 watts) so I'm planning to give this a try using those parts unless anyone has other advice.

 

My Heresy's are I's.  I really love them; they just need a little help I think.  

[fromnowon]

Sorry one more post if anyone is out there for comment:  I could put these together in parallel to get 21uF . . . 

 

Dayton Audio PMPC-1.0 1.0uF 250V Precision Audio Capacitor

Model: PMPC-1.0|Part # 027-210

 

Dayton Audio PMPC-20 20uF 250V Precision Audio Capacitor

Model: PMPC-20|Part # 027-252

 

Also, I noticed that the inductor for the woofer is suggested to go from 2.5mH stock to 2.2 . . . those are more expensive - is that a significant change, absolutely necessary?  I found this inductor which is 2.2 and not too bad - would it be acceptable and worthwhile?  https://www.parts-express.com/jantzen-audio-22mh-20-awg-p-core-inductor-crossover-coil--255-130

 

Thanks again for any comments!  It's been very helpful and I've learned a lot here.

[Pio]

Sorry one more post if anyone is out there for comment: I could put these together in parallel to get 21uF . . .

Dayton Audio PMPC-1.0 1.0uF 250V Precision Audio Capacitor

Model: PMPC-1.0|Part # 027-210

Dayton Audio PMPC-20 20uF 250V Precision Audio Capacitor

Model: PMPC-20|Part # 027-252

Also, I noticed that the inductor for the woofer is suggested to go from 2.5mH stock to 2.2 . . . those are more expensive - is that a significant change, absolutely necessary? I found this inductor which is 2.2 and not too bad - would it be acceptable and worthwhile? https://www.parts-express.com/jantzen-audio-22mh-20-awg-p-core-inductor-crossover-coil--255-130

Thanks again for any comments! It's been very helpful and I've learned a lot here.

Paralleling the caps you mention will be ok, about the inductor leave the 2.5 mH, will no affect since the essence of the mod is in the mid and hi section. Just my humble opinion. Any one with more knowledge will chime if i am wrong.

Best regards.

Pio

Edited May 27, 2016 by yo0

[Marvel]

You can leave the original inductor in the woofer circuit, but if you want to do a complete crossover rebuild, the Erse Super Q inductors are good for that position and in the grand scheme of things, not that expensive.

 

http://www.parts-express.com/erse-super-q-22mh-16-awg-500w-inductor-crossover-coil--266-906

 

Bruce

[fromnowon]

Thanks again Bruce. That's a good point. It'll be a new crossover except for the T2A.

Is the effect of changing from 2.5 mH to 2.2 mH in this position to make the woofer less attenuated (ie louder )in the balance?. If so that could be good . . . Thanks!!

[Marvel]

If my brain is still working, I believe it would roll off slightly higher. A calculator would tell you how much. I'm working in the yard and it's 88 outside, so I could be wrong...

[fromnowon]

 

Thank you for all the help!  I made all of John Albright's mods today . . . used two caps in parallel to get to 21uF, also used the Erse Super Q that Bruce suggested to drop to 2.2 mH.  

 

I decided to put jumpers between my resistor (which I glued to the board) and 0 & 5 taps on the autotransformer.  I did my best to keep it neat but I'm sure the soldering could be better.  I was concerned about damaging the T2A by applying the heat it would have taken to flow the solder better so I just made sure that it stuck solid and left it.  Seemed like the wax paper stuff wanted to melt.

 

Anyway - the speakers certainly sound more 'full'.  Vocals are really tremendous; even astonishing - they stand out more!  It's difficult to describe.  The sound is more live.  Stereo imaging seems better.  There is more depth to the sound.  Smoother with great detail.  

 

I really like the change.  It was apparent immediately when I first listened.  Big improvement!

 

You guys rock.

 

 

 

[Pio]

glad to know everything is good, enjoy your speakers!

 

 

best regards

 

 

Pio

[JohnA]

delete

Edited June 7, 2016 by John Albright