Automojo

Sure, yep. Audio is all about educating yourself, and finding out what sounds best!! Thanks!!

I completely disagree, because you can easily adjust the volume down to that of the 3. Compare the 2 volumes-subtract, and add the appropriate amount to adjust. If the woofer is the same III and IV-all that's important is what volume it sees. No mystery. Q etc would be identical. Unless the woofer model is different between the III and IV-then no. The only reason would be if your having rear port issues, but if you want to experiment, and perhaps prefer the sealed bass of the iii, I see little issue, IMHO of course. Power handling wasn't a issue I was trying to address., but I get it.... But hey, to each his own...…...this isn't a knock on the engineer who redesigned this-audio is all about making things work in your listening environment. Otherwise, what's the point??? Equipment is merely a means to a end.....musical enjoyment. Nothing too complicated. FIY, nephew had a internship @ Electrovoice in Burnsville. I was able to run a full frequency test on my modded AMT3's there, I'll post it here when I get the chance. Stock AMT3's vs my modded version. Pretty cool stuff!! You would be surprised how many of those guys tweak. I have been moding, building speakers for years. But of course, you have to have a understanding of how speakers work, and also some practical experience. Dicakson and Weams are excellent reading. By I also understand, some just stick with stock. Others afraid it effects value, etc, or both. I get it-for myself audio is a hobby-not a good investment. Life's too short to 'worship' equipment....enjoy the music! I personally don't see a issue with either. I imagine the stock IV's will be just fine for most. But theres no harm in exploring tweeks... I have found many times fine tuning internal damping can solve a whole host of bass/room issues, without changing your listening room around. Weems book has a article on how to construct a simple damping tester I have found invaluable over the years...works well with ported and sealed. FIY, I realize I haven't posted here much-however if your bored/etc done lots of work @ AK for years. Not trying to ruffle anyone, just pointing to the obvious... Occasionally I have floated over for Klipsch info. Appreciate the patience.

Randyh, explain the “definitely not” ...it seems to use the identical woofer as the 3’s, which are sealed. And sealed boxes are forgiving to slight increases in volume by their very nature. Alternatively the internal volume can be easily adjusted to the 3’s spec. I fail to see any issue with this...especially if you happened to have bass issues because of the rear port in your set up... The issue with plugging the port on many speakers is because the woofers EPB isn’t designed for sealed alignments... and can cause a number of electrical, and physical issues. Not the case here as the woofer appears unchanged from the 3. The crossover points may have changed between the woofer/ mid, but I doubt this would cause a big issue. Ine could easily find out by some experimentation Regardless... This is only an issue if you’re having problems with the rear port configuration.... HIfi has always been a hobby for me, I probably take after my father he built all his amplifiers preamp’s and speakers from kits I don’t have an issue experimenting and making things work in my listening environment... and learning how things work, particularly speakers because in my opinion nerves the most important link in the chain, and can have the biggest issues because of the listening environment... Regardless the “definitely not” comment seems to make a little sense to me, unless I’m missing something?

Even though the IV’s cabinet is larger.....remember you can still plug the rear port. It uses the same woofer.. and sealed configurations are much more forgiving for volumes differences. you could also adjust the internal volume with various types of materials if something was slightly off, but I’m assuming it will be close enough not to notice much of a difference. So if you think about it this way you can have two different types of bass box configuration easily changed on the fly A win, win IMHO! Some speakers still provide port plugs to change the bass box alignment This, on top of the midrange, tweeter phase plug and crossover update should be a second win win.

I think the internal wiring can add subtle details, and higher quality wiring=g resists corrosion/tarnishing. Rebuilt more then a few speakers-and at times-especially with my 2 pairs of highly modded ESS AMT3's, (clean, sealed/tight bass down to 25hz with woofer(now 9mm xmax-lower inductance) cab upgrades) used larger gauge wiring when able, and at the very least tinned hookup wire-available up to 14 gauge wire. With the added internal bracing, internal ceramic coating, and woofer upgrades they now tip the scales @ 135lbs ea. FIY those cork rubber blocks under the speakers-I got the idea from the Stereophile review of the Forte III. These needed 4 blocks, not 3 like the Forte's. I like the tweeks to the Heresy IV, very appealing IMHO. Any they weigh only 45lbs :)!! And IMHO the changes to the midrange, tweeter phase plug, and crossover changes are the biggest improvements to the Heresy. Sure the bass was extended, but the III's could easily get into the mid 40's with room gain. Try a sweep..... Regardless, I think the rear port had more to due with overall voicing, then merely bass extension. In regards to the post about sizing. Given the same woofer type-(the Heresy's woofer and a EBP that allows sealed or ported boxes)-ported properly will require a LARGER box vs sealed operation. I always liked the idea of the Heresy, just never could get past the poor driver integration-and uneven dispersion-never has a issue with the bass extension, because if you placed them properly they were fine for most music-IMHO. The III's did little to address these issues-IMHO-titanium drivers-nice-but kinda of a patch... This new model finally seems to have tackled this issue head on!! Pretty amazing they specifically explained how each of these earlier drawbacks were corrected. I'm going to audition a pair shortly, but if they have corrected theses issues-this will be my first new speaker purchase since the early 90's (KG 5.5's) And I have built, and modded many since then. MY 1980's ESS Heil PS1220's were sold to acquire the Klipsch-I regretted years later, and started modding/building my own speakers. While the bass won't be sealed, a correctly ported speaker such as this should come close-I can't imagine them spending all the time and effort, and sacrificing large amount of bass transient response for 1/4 octave of bass extension. It would quickly come back to haunt them. I think they could be a fun alternative to my AMT3's, and perhaps rival my MOJO modded AMT3's smooth, big, wide open dynamic range. Sure they won't dig as deep-but frankly 99% music doesn't need it.

Ported boxes in general are larger given the same size woofer. Looks to be a lot of worthwhile improvements, particularly in the midrange. The only drawback is the rear firing port, which will make placement more of a concern vs sealed box. All the extra extension below 58hz will be produced by the port. At least 12-15 inches from any rear wall I would imagine to prevent boom. There are some clever ways one may get around this if a certain placement is mandatory, but they usually don't look the best.

I know this was a old thread, but got hooked to reading it (as I see there is a pair locally-no affiliation on MSP Craislist-a little high$-wise). If the tweeter is too hot-just put a high power L-Pad from parts express or the like, between the driver and the crossover and be done with it. Not rocket science here, and it won't effect the quality of the sound, nor the amplifier damping etc. If the crossovers are damaged-that's another thing-but padding down the tweeter is simple. You could also pad it with a Mills wire wound in parallel or if you really wanted to get elaborate use a non shorting selector switch and a number of different resistors- but the L-pad would seem the easiest, as it would provide a wide range of adjustability. Also the advantage with the lpad is you won't change any realitive crossover points, as a added resistor might, as your changing the impedence the crossover "sees"-it might minor-but something to avoid IMHO-so I would L-pad it. I think some get to worried about things that will never effect the sound, but would benifit how the speaker sounds in your enviroment. A small hole is all that's required-no big deal. Some people claim, besides damping, there is a slight phase issue-I can't recall ever hearing this. A too hot tweeter would be more detrimental to the overall sound regarldess. Plus when you max it, it's essentially out of the circuit anyway. Klipsch should have probably L-padded this- but I can't recall seeing any other Klipsch with level controls. Probably some sort of desing philospthy--who knows. Plenty of speakers in the past had l-pads (especially those incorporating horns) or resistor selectors-the switch can get dirty with age, but a little Deoxit works fine.

I'm sure you can get a new woofer from Klipsch, I would think a used one would be difficult to find.

Nice job on the cabinet repair. Haven't tried the dampening materials, as I have been happy with the way they sound. I bought my new in 1996, one speaker had a rattle right out of the box, broken woofer screw. When I took it back, the salesmen claimed I had been messing with them-I told him he had to either fix them, or replace them, or I would give Klipsch a call, he replaced it. Since then, I have had no issues with them, no rattleing etc, just great sound. I drove them for years with a H/K PA2400,(170 wpc-100 amp current) which is a perfect match, lots of low end drive, and a sweet warm top end. I now use a H/K Signature 1.5 @ 200 wpc 130+ amps of current, and the sound even better. I think H/K amps are a excellent match for this speaker, brings out the high and mid details, without being harsh. Most Klipsch speakers well easily indentify weak links in your componet chain- something to think about before attempting mods-other than repairs of course. When I first got them, I had a Carver M-400, decent bass, but boy couldn't have been a worse match-sounded awful in the mids and highs. Just goes to show you equipment matching is more important than upgrading. I figure in another 10 years I will look at the crossovers, from what I see, they should be more than adequate componet quality wise. You have to be careful about substituting componets, as you make have a change for the worse. When Paul Klipsch was building speakers, he liked using plywood, because it resonated well with his drivers, ala KlipschHorn, Bella, something to think about. I really haven't noticed any resonace problems with my KG 5.5's, I'm sure the probably have resonace, but if so it doesn't seem to have a negative impact on the sound IMHO