Tarheel TJ Posted July 1, 2011 Share Posted July 1, 2011 Hi all, Been reading this site for years, haven't posted much though. I have a question about my '78 Heresy I's. I know that one of the changes made for the Heresy II's was to front-mount the mid and high horns so that they don't have to fire through the 3/4" baffle. It seems to me that this would reduce the diffraction quite a bit and may very well "clean up" the sound of the mids/highs. Has anyone tried to front-mount the horns on a Heresy I? Could you simple unscrew them from the rear of the motor board and drill screw holes in the front of the motor board? Seems like it would be a pretty simple mod that might yield some noticeable improvements. I just thought I'd ask here before I go drilling holes in my speakers. Thanks, Lee Quote Link to comment Share on other sites More sharing options...
Marvel Posted July 1, 2011 Share Posted July 1, 2011 You have to take the driver off the tweeter horn to get it through the hole, and you can damage the diaphragm while doing it. Plus, the shape of the back side of the horn doesn't quite allow it to sit against the baffle without a little work. The mid driver would unscrew, which owuld make it a little easier. There is a link on here somewhere about a couple of easy mods to the original Heresy, to smooth things out some, but I don't have it at hand. Bruce Quote Link to comment Share on other sites More sharing options...
moray james Posted July 1, 2011 Share Posted July 1, 2011 If you are considering the effort envolved in a project such as this I would suggest that you consider switching from the K-700 cast mid horn to the resin plastic K-701 mid horn which mounts from the outside and has a flange mount rather than the screw on mount of the K-700. The K-701 will not have the throat issues due to casting that the cast horn will. I would also suggest that you make new motor boards and install the K77 in the vertical position next to the mid horn. This way you match the dispersion patterns of the two horns. You will of course have to slide the mid horn over a little to make enough room for the tweeter and you might as well build a set of righ and left baffles. This will also break up cabinet edge diffraction found with the standard in line mounting configuration. Good luck and have fun. Best regards Moray James. Quote Link to comment Share on other sites More sharing options...
muel Posted July 2, 2011 Share Posted July 2, 2011 I'm not sure how you could move the K55 driver from the K-700 to the K-701 since the K55 is a screw on mount. Perhaps there is an adapter? I think I remember one that would allow you to connect the K53 to the K-700 but you would need the reverse of this. Have you recapped these yet? That will make a big difference. Anyway, I should have a pair of never used K-701 horns with gaskets - $20 plus shipping if interested. Quote Link to comment Share on other sites More sharing options...
Guest " " Posted July 2, 2011 Share Posted July 2, 2011 Could you simple unscrew them from the rear of the motor board and drill screw holes in the front of the motor board? the hole would have to be made bigger by about the thickness of the horn material times 2. Also, there was a dope from hope article about this that making such a change would not result in an audible difference. Quote Link to comment Share on other sites More sharing options...
Guest " " Posted July 2, 2011 Share Posted July 2, 2011 Could you simple unscrew them from the rear of the motor board and drill screw holes in the front of the motor board? the hole would have to be made bigger by about the thickness of the horn material times 2. Also, there was a dope from hope article about this that making such a change would not result in an audible difference. Quote Link to comment Share on other sites More sharing options...
moray james Posted July 6, 2011 Share Posted July 6, 2011 My bad: yes you could use an adapter but the easiest way would to simply switch to a K52,K53 or K61 (all mud magnets). If your one of the Alnico only fans then use an adapter I guess but I don't see the K55 as a particularly special driver and would prefer a K52 or other. That's just my preference so don't flame me if you disagree. Agree that crossover upgrade is money very well spent. Keep up posted as to how you decide to go with your Heresy's. Best regards Moray james. Quote Link to comment Share on other sites More sharing options...
Tarheel TJ Posted July 8, 2011 Author Share Posted July 8, 2011 Thanks everyone for the thoughtful responses. It sounds like the horns might be best left like they are. The speakers have new caps, Crites tweeters, reinforced cabinets, rope caulk on the horns, sealed backs, a bit of polyfill (not too much) and new binding posts. In other words, I've done all of the "standard" mods that are recommended on this forum. I am still experiencing a bit of harshness in the upper midrange (lower treble?) though. I thought that addressing the diffraction or reflection might help to smooth out some of these issues, but I could be off base with that assumption. Perhaps I should have framed my original question by describing the symptoms rather than assuming a solution. The speakers just sound a bit "hot" on sounds like high electic guitar notes, the upper end of female vocals, violin notes etc. I'm guessing that these sounds would fall in the 2-6khz range? Is there a mod to address this issue? Quote Link to comment Share on other sites More sharing options...
Ironsave Posted July 8, 2011 Share Posted July 8, 2011 The Heresy I is known to be a bit hot in the mids/upper mids. This is due to it's original intent was as a center. (Voiced for crisper vocals). Moray has some great ideas about removing deformities from inside the metal horn (throat) as well as some have recommended changing a capacitor to decrease the mids harshness. (You will have to use the search function). My solution is to just EQ the mids down a few DB. ( I am intrigued about cleaning up the throat of the mids though, and may do this soon). They sound fabulous right now, regardless....... Good Luck. Quote Link to comment Share on other sites More sharing options...
muel Posted July 8, 2011 Share Posted July 8, 2011 If you play it loud enough for long enough you won't hear those highs anymore. [] Or, actually, you might hear some high squeal that never stops... Tinnitus sucks! [:'(] Quote Link to comment Share on other sites More sharing options...
MechMan Posted July 8, 2011 Share Posted July 8, 2011 I always thought the HI sounded better than the HII. Quote Link to comment Share on other sites More sharing options...
Ironsave Posted July 8, 2011 Share Posted July 8, 2011 I always thought the HI sounded better than the HI. ??? Quote Link to comment Share on other sites More sharing options...
MechMan Posted July 8, 2011 Share Posted July 8, 2011 LOL...I fixed it, good catch. I do prefer the sound of the HI though. No idea exactly what it is, but my ears like it. Quote Link to comment Share on other sites More sharing options...
.thumb.jpg.1fb40d11b1cb3cc11ef3b2f0f7c8fe89.jpg)
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.