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Amp for Klipsch Heresy

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I'm planning to buy an amp kit to power my Klipsch Heresys. I really don't want to spend more than 600 usd but I'd like to get the max for my money. Right now amps I'm considering are....

Bottlehead Sex 2.1 - I like that it has a headphone amp as well, might be nice for my Denon D2000s. I've heard that even though my speakers are quite efficient they like having some headroom which I'm afraid the sex might not deliver.

Dyancoparts ST-35 - Love the price, is it pretty modable/very nice after mods?

Latino ST-70 kit - I'd do it, but I want to be %100 sure that it's the best option for me and that it would scale with any future upgrades well.

If anyone has any other suggestions please let me know, I appreciate all feedback. I haven't ever owned a true hifi amp for my Heresys, I just want to be blown away.
 
What kind of music do you like?

How loud?

What size room and how is it furnished?


I'm listening to Dixie Dregs "What If' through a 4.5W SE amp driving a set of 1978 Heresy speakers in a smallish room (4M x 6M) with carpet, drapes, panneling and brick walls.

It is not exactly party level, but quite loud enough to be in an ajacent room and enjoy listening to it.

Which sequence Heresy do you have?
 
Lot's of power is not needed, given the reasonably efficient speakers.

You will have money left over to buy music, if you build an "El Cheapo" with Dynaclone Z565 O/P transformers and triode/ultra-linear (UL) mode switches. :D If a CDP is your only signal source, a preamp is not needed.
 
One thing I should have mentioned is I do have some electronics and soldering experience but for this kit I'm really going to want something with instructions.

I have first gen Heresy's, they'll be in a room approx 4x3 meter, carpeted with some chairs. Is this room too small for these speakers?

I listen to a bit of everything, I look forward to hear what tubes do with female vocals and acoustic guitars.
 
One thing I should have mentioned is I do have some electronics and soldering experience but for this kit I'm really going to want something with instructions.

I have first gen Heresy's, they'll be in a room approx 4x3 meter, carpeted with some chairs. Is this room too small for these speakers?

I listen to a bit of everything, I look forward to hear what tubes do with female vocals and acoustic guitars.

thehof,

I also have HERESY 1 "HBR". These speakers have been often denied, but are wonderful...

But let me tell you that first there is one little very easy and removable mod you can add to the crossover to make them sound "quietly" with nearly any amp.

The mid and high section are at least +8db over the woofer section : that's what I measured on 2 pairs of Heresy 1 of the early 80's (both fitted with the k-77, k-53 and k-22 speakers, and E2 crossover).

Here is the mod, which introduces resonances damping of the mid / high / transformer horn sections, giving a quasi-linear frequency response, according to the measurements I have made on MLS signals :

An externally hosted image should be here but it was not working when we last tested it.


Here is the placement of my Heresys : in some kind of "horn"-shaped ceiling, in fact, which gives adequate bass response (Klipsch suggests wall angle placement...) :

An externally hosted image should be here but it was not working when we last tested it.


I use tube amps (SE, PP, OTL, DIY or vintage) or solid state amps (vintage) from 3W to 75W, with or without NFB.

A+!
 
I've been listening to a pair of Tri-Trix MTM speakers, with a pair of Dynaco Mark IV's that I custom built. These loudspeakers have a sensitivity of around 89 to 90db, and these amps are more than enough, and the sound is phenomenal ,I'm sure the ST-70 would be the way to go, even using the stock driver board.
 
One thing I should have mentioned is I do have some electronics and soldering experience but for this kit I'm really going to want something with instructions.

I have first gen Heresy's, they'll be in a room approx 4x3 meter, carpeted with some chairs. Is this room too small for these speakers?

I listen to a bit of everything, I look forward to hear what tubes do with female vocals and acoustic guitars.


No, the room should be fine with the Heresy speakers. You may find you will want to do some adjusting of the room by adding a tapestry or some drapes if it is too reflective.

Do you like Bonnie Raitt? She sounds very good even with the low power amp I'm running.
 
This is a question near and dear to my heart because I have had a similar experience, though I arrived from the opposite direction (I built the amp and then searched for speakers). Pardon the wordiness.

I not-too-long-ago acquired a pair of Heresy II's for use with my Tubelab SSE because I wanted something more efficient (the next most efficient speaker in my stable was ~90db). I can say that, for me, the ~5wpc is plenty loud enough for CD or vinyl playback. In my 20ft x 16ft room, the volume knob is usually somewhere around 12 o'clock for listening or 9-10 o'clock for background music. I had it up to almost 2 o'clock this weekend while I was painting in another part of the house, but that would be too much for me if in the same room.

Speaking of volume and wpc, dynamics must also be addressed. For what I listen to (mostly jazz, classic rock and modern acoustic groups) I have not felt/heard the setup running out of dynamic headroom. Do my wife's Lady Gaga albums pound like they did when I had a big solid state and multiple subs? No, but that's all the more reason for it to stay off my turntable. Does it play back Pink Floyd's largest anthems with authority? Absolutely. I have not yet felt the need to install an Ultralinear switch (for ~15wpc). By the way, Heresys and an SE amp will tell you about bad mastering, worn vinyls, low bitrates, etc, but not to the point of distraction.

You know what your speakers basically sound like, so general FR and SQ probably doesn't need to be explained to you. As you must have read though, Klipsch horns like tubes. I don't have any of the midrange honk/shout or overly-bright FR that some complain about with Heresy's (no doubt when used with SS HT receivers). In fact, I had the opposite complaint at first. They were just slightly dull sounding, but I knew that this wasn't an issue with the amp because of the characteristic tube sparkle it had demonstrated on previous sets of speakers. Luckily for me, and my pair of '86 Heresys, rebuilding the original crossovers put any complaint about the lacking treble/mids to rest. They're now pumping out natural mid ranges and wonderful cymbal decay. Bass is there too, to the extent the Heresys can muster (and better with KT88 tubes).

The Heresy-SSE combo will be the heart of my living room setup for the foreseeable future. While I'll continue to tweak here and there, I really haven't been left wanting for anything from it, given the constraints I had to work with (budget, modest size, sufficient volume, but excellent SQ). I will eventually have a colossal four-digit-wattage solid state monster in the basement, too. But that's where monsters belong.

My build cost me about $400, tubes and medium size OPTs included, but I had a chassis on hand. A $600 budget would buy the very best iron and a nice chassis.

Tubelab's redesigned website has just about all the info you'd need and the Tubelab section on diyaudio.com is fairly active to help with other questions/uncertainties/troubleshooting.

YMMV, but that was my experience with Klipsch Heresys and a DIY tube amp.
 
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a pair of Heresy II's
I don't have any of the midrange honk/shout or overly-bright FR that some complain about with Heresy's (no doubt when used with SS HT receivers).

Yes, Sodacose. The HERESY II doesn't have the same crossover as the HERESY I "HBR", and it is close to the mod that I have done according to my measurements on my HERESY I (I dicovered afterwards that the values used by Klipsch were 11 ohms and 21µF...). This dampens the excess of level in the hi-mid region, so your note is not suprising, and like me you would notice the same using a solid-state amp in the hi-mid response.

I retrieved the complete explanation about my mod, with impedance and response curves. You really should consider this, thehof :

An externally hosted image should be here but it was not working when we last tested it.


A+!
 
Thanks a bunch.

I guess I'll just have to test two sets to see how they respond.

The set I bought in 1977 are Black Ash finish. The set I bought second hand are black Birch Plywood finish, and are a bit ratty, but sound just as good. They may be Heresy II, I'll have to look and see if I can tell.
 
I have the original Forte's. Same drivers I believe, different alignment and I find it fairly well balanced, no real shoutiness until you give it some juice. I think they, and Heresy's are fine on a small amp even if SS.

Forte II have different speakers than the Heresy I and a passive radiator coupled with a 12" woofer (which is I believe the K-24 like in a Heresy II ?).

I do not remember about Forte I, but I think that there was no passive radiator and a 15" woofer.

I am sorry but my memory is not faithfull and my Klipsch documentation is out of reach for the moment...

Nonetheless, good speaker units, indeed !

A+!
 
I originally ran a Sony STR-5800SD receiver with my Heresy speakers with no noticable shoutiness.

The STR5800SD is rated for 55W (US Model) and measured slightly more.

Using a LED VU meter (Radio Shack) I typically saw 1W peaks and 32mW average.

The STR5800SD was the last model before the SONY V-FET amp, which a friend who worked at a stereo shop advised me not to get because they were blowing output transistors. The receiver I got was the last one in stock. I need to dig it out one day and see how it sounds compared to a tube amp.

My sister had Heresy speakers as well, but with the smaller STR-2800SD. It didn't sound near a nice.

I was wrong on the first pair of Heresy, they are H-WB from 1977, but I bought them in 78. They are Black Laquer Walnut with black grill cloth. They are successive serial numbers 51R480 and 51R481.

The second set are 161Y862 adn 161Y864 HBR 1982 Birch Raw. So they are non sequencial, first series although near the end of the production.
 
scott17 had some bulletproof KT88 SE amps for sale before (with quality components and instructions) and he has some other projects on the go. Might want to contact him to see what his suggestions are.

George at tubelab.com is another fine gentleman to deal with and his Simple SE is very flexible and there is a lot of write up, help, modifications, and pictures, of the various builds in on the tubelab sub forum here at diyaudio.com. Further information, pictures, the design process, and the instructions are on-line for your perusal at his website. Check it out and see if this suits your tastes.

With the money that you save, you can come back to diyaudio.com's store and purchase the Nelson Pass designed Amp Camp Amp; Class A solid state mono blocks powered by laptop bricks can probably never sounded as good as this running at 5 watts of power. And Nelson Pass recommends the use of regular components; so no exotic expensive parts that are hard to obtain. Yay!
 
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originally ran a Sony STR-5800SD receiver with my Heresy speakers with no noticable shoutiness.

Yes. These amps works well... Here on the picture you can see my SONY STR-6055.

These amps have a damping factor of circa 30-40, where a 300B SE amp has only circa 2 : this explain why the shoutiness of an HERESY I is tamed (if your speakers are HI not HII).

An externally hosted image should be here but it was not working when we last tested it.


A+!
 
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