| inrank |
i thought i would write a 'basic' review of my new speakers using the Omnes Audio L8 full range driver.
after listening to this for a while, and i guess it has had about 30-40 or so hours running in time, i think either i have got used to the slightly top heavy treble or it has smothened out a bit because it sounds really good now.
i am not sure what i am describing but the mid range, and especially the vocals seem to come out a lot from the speakers and i could swear they were just in front of me, and the actual voices seem very 'live' or real, as if they were in my room not in a padded recording studio.
there is not really any bass (not that i expected any) but seems just right if i am listening late at night and with relaxing music, dont really feel the need for a sub, but i do with louder rock etc.
i do not feel the need for a tweeter although if the treble is a bit to much you could cut it off lower and add a tweeter.
i cant really say much bad about it because for £100 a pair they whip my Kef XQ1's on imaging, dynamics and vocal reproduction (the kefs are better at overall accuracy and bass).
about the actual units, the cone is very stiff and it is very hard to move the cones manually and they hardly move even at ear splitting levels and the woofen phase plug looks very good set against the black cone and the full paper (all-in-one) surround looks very neat.
a rubbish pic of them in my room (obviously they would be aligned for listening ;) )
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| inrank |
some more photo's...
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| Klimon |
Good to hear a review of these, the FR looks very linear but that's only a first indication (if it's not too fraudulent as with some other speakers), I'm mostly interested in high-mid and treble smoothness for replacing Beyma 8ag/n that have very similar T/S data but some problems. Are the L8 phase plugs attached to the membrane or mounted on the polepiece (with a narrow gap between plug and speaker membrane)? Most manufacturers just glue them on the cone, fast and easy, neglecting more important issues as cone-mass and a-voiding resonant voids...
Simon |
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| inrank |
| the phase plugs do not move so i assume they are attached directley to the magnet at the back as there is a hole in the rear of the magnet and you can see the back of the wooden phase plug and there is a gap between the phase plug at the front and the voice coil. |
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| Henkjan |
| for more bass mounting them in "das viech" could be an idea? |
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| inrank |
| is than not a horn? and dont the L8's have a too high QTS? (and i am using them with a sub so bass isnt a problem) ;) |
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| Scottmoose |
| Yes, it's a horn, and I can't see this driver working too well in it with a Q of over 1.0. Having said that, Vas is pretty low, so it's not impossible that it could be used (horns do not automatically require low Q drivers) but it would have to be designed around it from scratch. |
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| GM |
Greets!
FWIW, based on published specs, Professor Leach's math suggests a 61.75 Hz Fc:
Vr = 148.63"^3
St = 42.04"^2
Am = 1891.77"^2
Am (min.) = 945.89"^2
M = 0.857 with an inital 3.54" long straight section and use a horn program to find its expansion length based on desired mouth area.
GM |
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| el`Ol |
| I have been asking myself for a while whether the Viech would work, since TSPs of Omnes an Beyma are very similar. I hope someone will try one day. |
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| Scottmoose |
| Greg -are we talking the 'On the Specifications' paper here? I really should re-read that. |
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| Klimon |
| quote: | | I have been asking myself for a while whether the Viech would work, since TSPs of Omnes an Beyma are very similar. I hope someone will try one day. |
I'll try it when money permits. I've got a pair of VIechs and damared the Beymas to death (too much makes a dull sound, two layers is a vast improvement) + can't live with the high-mids even after a large array of tweaks. Last time I operated the Viechs it was with a very broad notch filter from around 2 to 5k (whizzer was already cut of + replaced by neodymium tweeter) which helps the metalic high-mid sound but when operated without notch (bad balance) you notice how much you do lose with a notch-filter (has something to do with naturalness of soundstage). As the Omnes audio is very close to the Beyma's regarding T/S + has a nawi cone (generally better than whizzers) + hopefully a better top-end (although this FR shows a 3,5khz peak that troubles me a little, don't won't to resort to a notch filter again http://www.lautsprechershop.de/hifi.../omnesaudio.htm) this might be an improvement over the Beymas...
| quote: | | the phase plugs do not move so i assume they are attached directley to the magnet at the back as there is a hole in the rear of the magnet and you can see the back of the wooden phase plug and there is a gap between the phase plug at the front and the voice coil. |
Very good to know, one extra point for the L8 :)
I'ld love to hear some more subjective evaluations of these drivers.
Simon |
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| GM |
Greets!
Yeah:
Title: On the Specification of Moving-Coil
Drivers for Low-Frequency Horn-Loaded Loudspeakers
Publication: AES-J, Vol. 27, No. 12, pp. 950 (1979)
Author: W. Marshall Leach, Jr.
and
Title: Author's Reply to "Comments on Reactance
Annulling in Horn-Loaded Loudspeaker Systems"
Publication: AES-J, Vol. 29, No. 7, pp. 523 (1981)
Author: W. Marshall Leach, Jr.
GM |
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| Scottmoose |
Thanks Greg. I last looked at it when I was down with the dreaded lurgy, which probably put me off. I'll re-read today.
Regards
Scott |
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| inrank |
thinking of adding some woofers in the same baffles (one per side)..... as before, whats my best bet?
idealy (i know its harder) but i would rather go passive with the low pass for the woofer and keep the L8 full range.
from what i have seen the Eminence Alpha 15's look good, V.cheap, QTS of 1.26 and fs 41Hz.
and should i roll them off at the baffle step freq? (280Hz)
how much power do they need?
regards |
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| James D. |
The Beta 15s are better than the Aplha on an OB. connect the drivers in series and cross over between the two at 100-300Hz to suit the components you have. Use a cap across the Beta 15 and an inductor across the Omnes for the crossover. Mount the Beta 15 near the floor to use the floor lift to offset the baffle rolloff...
James |
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| inrank |
and another thing, is there a way to tame the treble a little, symbals in particular seem strange, sort of distorted and 'samee' and 'rings' a bit if you get what i mean..... would adding a tweeter say at 10Khz help with this?
or looking at the fr plot on the spectrum audio website, would the normal L8 with a tweeter be better?
noticed this symbal thing when listening to rock (soft and classic) and it spoils it really... :( |
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| Scottmoose |
| There look to be some peaking in the graph, though the thing's so small it's difficult to be sure. The standard version certainly appears to be flatter across that region -the special edition version looks to me as if they were trying to create a cut-price B200 -not exactly an eaasy task. I'd probably consider them a wide-range rather than full range driver, and bring a nice tweeter in around 8KHz or so, which often works well as the XO is well out of the critical range. |
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| inrank |
| yeah, with acoustic and simple vocal music, they are brilliant, just with more complex and rock music that 'ringing' happens, but i suppose thats just what full range drivers do? :D |
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| Scottmoose |
Not the B200s, the better Fostex drivers & Lowthers (providing you're not going insane with the volume knob). But they cost a whole lot more, and your Omnes clearly are a heck of a lot of driver for the money. I'm impressed by their paper specs & their appearance. The build looks very good too.
Oh yes: Try the album 'One of these Nights' by The Eagles through them -it's a great album, and doesn't cost much. Much musical pleasure. Also, importantly, it's the sort of music they should lap up, so if you can hear something wrong, you should be able to isolate it PDQ. |
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| Klimon |
I see my previous link wasn't the right one, here is a FR graph measured by a german audio mag; standard L8: http://www.lautsprechershop.de/pdf/omnesaudio/l8.pdf
BTW I don't see the point in the spectrumaudio modification; the text mentions lower harmonic distortion + better treble extension but all I see is a huge rise (5 to 10db if my eyes can read the tiny graph) from 4 till 10k and indeed, a small lift above 10k which fulfills the claim of more treble. Which means that to avoid the ear-shredding part you would have to cut off around 5khz and lose the whole idea of a fullrange driver. I guess you could call it a special version :rolleyes:
Simon |
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| Scottmoose |
| Lowther's and the B200 have the same characteristic. Toward the upper end it's outside our most sensitive region of hearing, so it'll likely just make it seem detailed. For myself, I'd stick with the standard version though. |
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| Klimon |
I'ld agree for the most part (that's why the delayed roll-off is only a slight benefit) but the low treble region where it already goes wrong (4-6khz) can cause more nuissances. Lowthers aren't really famous for their non-shout character either; strange I haven't read anything bad about the B200 although the rise in response is very obvious. Maybe FR graphs aren't that determining after all........
Simon |
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| Mutley666 |
| Perhaps the intent of the Spectrum modification is to lift the of axis treble response..... |
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| Henkjan |
| but when that messes up the higher mids than I don't see the point.... (there was the same discussion on forum.zelfbouwaudio.nl, same result....) |
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| Scottmoose |
| True enough. Still, some people like a slightly hot upper midrange as it subjectively gives more forward vocals. Not something I like, but to each their own! |
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| lovechild |
Hi,
did someone really try listening off axis to the spectrum-L8?
A 8" FR driver, with no whizzer, has a very directional response from the mids on. If the driver is set up to have a linear response on axis, you will have less mid/high frequencies energy in the room, than bass and low mids (which are radiated into 1/2 or even fullspace). So in theory, as the reflected waves do also have an influence on the overall timbre of the sound in room, a rising MF/HF response can compensate for that while you still have a linear reponse when listening with the speakers not tied in (off axis 20 - 30°).
best, LC |
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| Klimon |
| quote: | | A 8" FR driver, with no whizzer, has a very directional response from the mids on. If the driver is set up to have a linear response on axis, you will have less mid/high frequencies energy in the room, than bass and low mids (which are radiated into 1/2 or even fullspace). So in theory, as the reflected waves do also have an influence on the overall timbre of the sound in room, a rising MF/HF response can compensate for that while you still have a linear reponse when listening with the speakers not tied in (off axis 20 - 30°). |
Doesn't make sense to me. If the aim is to have a radiation pattern of which the sum is as flat as possible in all possible directions it would seem beneficial, say at a supermarket. If you're sitting in your couch on-axis with the speakers as most critical listeners probably do I can't imagine a reason why you should sacrifice on-axis FR. I think you'll need lots of imagination to turn the better off-axis behaviour into a benefit that outweighs the loss in on-axis response, in the listening environment I suspect most people here inhabit. I never heard people champion the Lowther high-mid shout as a benefit that makes for better off-axis response, some do tilt their speakers to make it more bearable ---- but that's only a remedy after the harm has been done.
Groets,
Simon |
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