Epos ES14 (MK1) equal or better out there?
- Thread starter graeme h
- Start date
RustyB
Registered Ginga
I believe Im correct in saying that the designer was Kevin Voecks, a man generally reckoned to be among the more able designers. Interestingly, he eventually found his way into the Harman operation, as did Robin Marshall.[/QUOTE]
No, KV was responsible for the J/III, which was technically more accurate but not regarded as being as musical in some circles.
No, KV was responsible for the J/III, which was technically more accurate but not regarded as being as musical in some circles.
James
Lord of the Erg\o/s
In my experience, a single cap on a tweeter - particularly with a value that effects transfer within two octaves of its fundamental resonance (fs) - is a recipe for mistermination. This causes a peaking in the lower reaches of the tweeter that is manifest as artificial presence (at best) or sibilance and harshness (at worst).
Judging by the size of the mid-woofer (8"?), the tweeter would need to be crossed no higher than 2.5kHz, and maybe ideally 2kHz. This would require the tweeter to have an fs of around 500Hz or lower. To have a low fs and extended top-end would call for a world-class (expensive) tweeter from the likes of the Scan-speak Revelator range. Maybe the ES14 has such a tweeter, but then again maybe it doesn't.
James
flatpopely
Prog Rock/Moderator
The ES14s don't have harsh or sibilant treble, or at least the ones I have heard don't. Measurement is not always the be all and end all of design.
Robert
Tapehead
A few isoplanars are good candidates.
The fs of the Mk1 tweeter was around 600Hz. I cant speak for the MkII, but I would imagine that the fs would be a higher, given that its SEAS dome/coil/suspension was much more conventional than the Epos built Mk1.
The Mk1 tweeter did not rely on just the series capacitor for the high-pass filter. There was some mechanically contrived assistance from the dome suspension. The suspension had a very narrow convolution with compound curvature and varying cross-section thickness (it was a moulded part) and began to stiffen significantly below the crossover point. The effect was to introduce an additional pole into the inherent second order characteristics of the tweeter.
flatpopely
Prog Rock/Moderator
Just send me a pair!
RustyB
Registered Ginga
The crossover point is at 3.5k, and the response decays smoothly at 12 dB/octave.
Above that, however, the response is very uneven, with a prounced peak at 10k.
The Seas ali domes of that era have very smooth published FR's, and to me sound a lot nicer than the ES14 mk2 tweeters.
I have some in my Alexander Auroras, which also feature a direct-coupled mid-bass, in this case a bog standard Seas poly driver.
Above that, however, the response is very uneven, with a prounced peak at 10k.
The Seas ali domes of that era have very smooth published FR's, and to me sound a lot nicer than the ES14 mk2 tweeters.
I have some in my Alexander Auroras, which also feature a direct-coupled mid-bass, in this case a bog standard Seas poly driver.
sq225917
Bit of this, bit of that
Yes, seems like there is truly a world of difference between those who simply slap some OTS drive units into a box and add a crossover and those designers capable enough to scratch build.
I dont think that your observations are too much of a surprise. Im not an expert in acoustics or speaker design by any stretch of the imagination, but I believe that its necessary to optimise the shape and dimensions of the aperture that a tweeter dome looks out from. At higher frequencies the aperture is almost certain to act as a waveguide if it has any appreciable thickness. Ive not looked very closely at a MkII ES14, but I doubt that any changes were made to the tweeter front plate to optimise it for the SEAS dome. The peak at 10kHz that you mention certainly points toward something not being quite right.
The fact that the MkII tweeter response rolls out smoothly at 12dB/octave indicates that the SEAS dome and suspension applied no particular constraints on the dome excursion. The Mk1 tweeter, with its restraining surround, had roll-out characteristics which began to morph into a sort of quasi third-order as the frequency decreased.
On the question of the Snell J, who did design the J/II. From what you say about Kevin Voecks not being responsible, I guess that it must have been the J/III that I heard.
A good set of 401s driven by a suitable amp are a completely different proposition to ES14s. IME they are just as cohesive and transparent in the midrange as 14s and have a smoother treble response. Almost goes without saying that the 401 bass response makes ES14s sound decidedly broken. I could go on, but it always upsets the natives when I do.
Mr Tibbs
James
Lord of the Erg\o/s
I made no reference to measurement; just pointing out a fact that a single cap on a tweeter *can* result in mistermination under certain circumstances. I also made no reference to whether the ES14 was harsh sounding or sibilant.
I know you love your ES14s. But seeing that I did not comment about their performance, I'm somewhat surprised at your defensive response.
flatpopely
Prog Rock/Moderator
I suggest you re-read your post. I'm not being defensive just stating my opinion about ES14s.
James
Lord of the Erg\o/s
I have, and I still don't understand your counterpoint, especially about "measurement is not always the be all and end all of design".
Care to explain?
S-Man
StrivingON
401s have a slightly boomy bass and plenty of it. ES14s have pretty tight and tuneful bass, but not much of it. ES14s have a more immediate sound and 401s have a wonderful room filling effect. Both are great speakers when driven properly.
There are (a few) greater things out there though. IMO.
flatpopely
Prog Rock/Moderator
One needs to listen to any design in conjunction with theoretical application of the component specifications.
david ellwood
Kirabosi Kognoscente
Have you been drinking?
flatpopely
Prog Rock/Moderator
David, open invite for you to pop over during the Christmas hols and have a listen. I will, if ok, pop over to listen to the Briks. Perhaps we will both then have a reference point.
Honest offer, no agenda.