EV Esquires

mhardy6647

Since these are sittin' on the beautiful Polkstand replicas made by Rev. Hayes here, acquired in a generous "Karma" fashion by me a while back!) - I thought this was worth mentioning here.

The real LR hifi is pretty much now moved into its new home at House 4.0 in NH. House 3.0 still needs some decent hifi hardware for listenin'... even if made up of odds and ends.

The current odds and ends in the living room:
EICO ST-40 (push-pull 7591 in a simple, straightforward self-bias configuration for about 20 wpc).
Magnavox-branded DVD (cheap and cheerful in the extreme but surprisingly good sounding)
Cosmetically mismatched pair of EV "Esquire" speakers (both acquired - very inexpensively - one at a time, on eBAY years ago).

Gary Kaufman (www.the-planet.org) very kindly re-habbed the ST-40 (which I found on the scrap metal pile of our town dump!) for me about a year ago. Gary has my thanks and appreciation for doing it (I'd have gotten around to it... maybe... someday...)!

The three-way Esquire is, I'd opine, what Col. Paul W. Klipsch wanted his "Heresy" to be - a small, sensitive yet truly full-range (well, compared to the Heresy) loudspeaker. I've posted about these before :-)

For today, all I'll say is that I've had some quality time to listen to this combination of hardware and it's really pleasing to a guy who has become an Altec devotee in recent years; present, clean, smooth, and well balanced with the dynamics that makes a good recording sound like the performers are in the room. Even with a push-pull amplifier! Whoda thunk it? :-)

At any rate, it was a beautiful winter holiday in MA today so I managed to snap a few better (not great, but better) photos of the electronics and one of the speakers (the other one is actually much better cosmetically, but its original cane grille is, I believe, non-removable).

Face

Why is the HF driver sideways?

mhardy6647

Because it is a diffraction horn - that orientation gives the widest horizontal dispersion.

Klipsch sometimes installed the EV T-35 (which they called the K-77) horns correctly (long axis vertical, as shown above), e.g., in the original - and uncommon - version of the Cornwall... but more often than not, installed them rotated 90 degrees (counter to EV's recommendation)... who knows why?! Most Cornwalls, the Heresy, and the LaScala, Belle Klipsch and Klipschorn all have the T-35 drivers installed "wrong".

EDIT: d'oh, I missed the ";-)" in Face's post! :-P

At any rate, I guess Bosch owns the EV brand now - on the bright side, they do still have much of the legacy EV documentation online - but it's even harder to sort through now than it used to be! :-(

I've just skimmed through a number of the the EV compression tweeter and horn docs online - they generally don't explicitly say to mount them vertically, but they do show them vertically. The docs for the EV/DuKane T-3500 "Ionovac" plasma tweeter (a seriously cool piece of hardware, by the way) do provide some explanation of the ideal very narrow width of a diffraction horn...
http://www.electrovoice.com/downloadfile.php?i=971183

Face

I see, my only experience with horns is the SEOS project...

Here's a blurb on diffraction horns: http://library.thinkquest.org/19537/Apps4.html

As for them installing them incorrectly, I just read something about this recently, I'll post a follow up when I come across it again.

halo71

May be a dumb question...but why does the ad show them on their sides?

mhardy6647

OK, OK, OK... ;-)

The use of compact speakers began in the late 1950s when more ordinary folks were moving into home hifi - for aesthetic reasons, it became popular to place speakers sideways on bookshelves - thus the term "bookshelf speaker" - which probably started with the Acoustic Research acoustic suspension speakers ca. 1955 but persisted for small "monkey coffin" designs (whether sealed or ported) at least into the 1980s. I guess the modern term for such speaker enclosures is "monitor" (very different than what "monitor" meant in the 1950s; my Altec Duplexes were monitors, and nearly universally used ones at that for several decades).

mhardy6647

As an FYI (not that it will really help the vertical/horizontal tweeter discussion too much!) EV has the manual for the later Esquire "200A" version (which used a more generic 5" cone MR driver in an 8" metal basket/baffle) online: http://www.electrovoice.com/downloadfile.php?i=971088

EDIT: The docs for the coaxial 12TRX and 12TRXB state that the horn "slit" should be vertically oriented for best HF (lateral) dispersion... http://www.electrovoice.com/downloadfile.php?i=970304

Mr. Bubbles

So the correct orientation for the horn is with it's longest dimension vertical? I think this is what i understand from above. If this is the case, and (I also think I understand you to say that) these are mounted correctly, when positioned with the cabinet horizontal as in the ad the horn is then horizontal. I know little to nothing about horns other than they generally don't please my ears. This just got me to thinking if I've been listening to much of them incorrectly maybe that has affected my opinion of horns.

mhardy6647

There are lots of different kinds of horns; the T-35 uses a "diffraction horn" which gives best horizontal dispersion with its long axis vertical. An Altec 511 or 811 sectoral horn will be horizontally oriented for its 'best' horizontal dispersion. There are other horn "flares" and configurations, both classical (think about trumpets and tubas!) and much more modern. Today there is a moderately fashionable horn variant that is referred to as a "waveguide" (which is at least partially meant as rebranding for the "I don't like horns" crowd, I think!).

You may well not like horns - on the other hand, you may just not have heard a good implementation of a horn loaded compression driver yet! :-) Either way is OK; there's room for a lot of different tastes in the reproduction of sound.

For the record, I am not a big fan of the T-35 horn tweeter family (although the top-end version, the T-350, is a noticeable step above its lesser cousins, the T-35, T-35B an TW-35 models). They're not very extended and they can be ear-gougers (listen to a Klipsch Heresy sometime!). They are, for whatever reason, much better behaved in the Esquire (perhaps the XO frequency; I don' t know). Another better-sounding implementation of the T-35 horn tweeter is the EV "Wolverine" series 12" coaxial speaker called the LT-12... but now I am getting into the rather arcane :-)

Tbone289

That's a beautiful vintage setup. I would love to hear the Esquires. What year(s) were they produced?

mhardy6647

roughly the late 1950s to early, perhaps mid 1960s. The other one of the "pair" is considerably prettier, with a woven cane grille.
For about 100 smackers in toto for the pair, though, I cannot complain that one of 'em is pretty scuffed up and has (I think) a replacement grille (and no emblem on the front) :-)

The scan I posted is from the 1961 Radio Shack catalog:
you can see it in its original context on page 50 of http://www.radioshackcatalogs.com/catalogs/1961/

EDIT: The same lineup is also in the 1960 catalog; only the Regal is in the 1959 catalog... don't know when they stopped making/selling them...

mhardy6647

I don't know what an LSAF is...

mhardy6647

ahh...

I am not necessarily a proselyte for horns (being a guy who also owns a pair of Quad electrostatics as well as numerous conventional radiator loudspeakers) - but if one develops a taste for their dynamics and that "they are here" presence that good ones can deliver... it's kind of hard to go back, full time, to the polite little monitors sitting demurely somewhere looking pretty ;-)

Mr. Bubbles

Mhardy thanks for the response to my earlier post.

can you tell me why if the horn you describe sounds best horizontally with it's vertical axis being it's longest dimension, why it is shown in the add rotated 90 degrees to that. I read your previous description of the bookshelf setups, but would orienting the cabinet in that manner not place the horn off of it's best axis for sound?

I have heard several Klipsh models, including the Heresy. Plainly put, they hurt my ears and sound nasty in their higher ranges. they are probably a lot of why I don't accept horns any better than i do. I hear ( and read) that so many people love them and rave about them, but I don't get it when I hear them myself. To me thay are much too harsh. The only horn I have heard (thus far) that i could listen to for any length of time was a very large JBL with what i think was referred to as the baby butt horn.

Just one more question; you refer to the horn you described earlier as a diffraction horn. Do not all horns use the physics of diffraction as their principal means of guiding the sound wave out into the listening environment in the way the designer of the horn wanted?

mhardy6647

OK, I missed the "edit" time window digging up this photo, so I had to add it as a reply to my own reply... nonetheless, I figured :-) I owed youse guyses a point of reference as to my own personal "Holy Grail" horn assessment (and I've heard quite a few, including some more physically magnificent and dominating than these) - Gary Kaufman's Altec "Voice of the Theatre" A5 cabinets with 515 drivers, topped with Altec 1505 tar filled multi-cell horns and 288 drivers, with Hiraga crossovers and augmented with split Altec A210 'subwoofers' (not sure what drivers Gary has in his half-A210s). These are, in my book, absolutely superb with a high-ish-powered single-ended 211 amplifier of Gary's own design and construction.

Read more at: http://www.the-planet.org/A210.html

And see some photos of Gary's amp near the bottom of the page at: http://www.the-planet.org/nnetg.html

(you can also probably kind of tell that Gary's hifi room was the inspiration for my new one!)

mhardy6647

I am woefully unequipped to write about the physics of horn-loaded transduction :-(
The T3500 doc I referenced earlier does a fair job of explaining the diffraction horn(although the figures are apparently lost to the Ages).
http://www.electrovoice.com/downloadfile.php?i=971183

Here's a pretty good treatise on horns from a Peavey engineer...
http://aaassets.peaveyelectronics.net/pdf/qwp1.pdf