Thank you! Looks like an awesome project.
I want to use low power SET amps so while this looks really great I am looking for something much simpler in particular an Open Baffle using the Lii Audio Fast 15 speaker or Fast 10.
Thanks and good luck on your project.
Regards,
Steve
So I obtained an Apex 220 measurement mic, was able to connect it to a Tascam US-122L providing 48V power and A/D services. The following two responses were taken, using REW's 48th octave analyser.
I was playing a 15 minute pink noise recording - with much liberty on Equalizer APO's 31 band EQ as needed to effect the responses shown. One with sub, one without.
Unsure if I can duplicate or come close to the EQ settings in Daphile, my convenient non-Windows player.
Thanks for looking!
I was playing a 15 minute pink noise recording - with much liberty on Equalizer APO's 31 band EQ as needed to effect the responses shown. One with sub, one without.
Unsure if I can duplicate or come close to the EQ settings in Daphile, my convenient non-Windows player.
Thanks for looking!
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Not sure you what you mean by much simpler - no bass helper? I don't think you'll get enough bass from a single Fast-10S on an OB.
For my Fast-10S units I plan to use an SE-OTL amp of about 1.5W pc.
Hi, someone on this forum mentioned the use of a "SLOB" and provided a link. This setup included a large driver for low frequencies. I am looking for an Open Baffle single driver solution (no crossover) for either a Decware ~2W SET amp or a Dennis Had 6W- 10W SET amp. Decware offers a "Big Betsy" but it is out of my price range.
I ordered a Caintuck Audio that uses the same Lii Audio F15 drivers but haven't had the chance of hooking everything up because of some renovation work going on at my house (the waiting is killing me). I'm super intrigued by the Decware Big Betsy Open Baffle offering and thought I would try my hand at building something. I thought I would be able to buy some Butcher Block in the rough to keep the costs down and then figure out a way to cut it to the dimensions and shape of the Big Betsy and Caintuck speaker - if I am super happy after hooking up the Caintuck's speakers I may give up on this but I am very intrigued by Open Baffle and single driver solutions. I have an Omega Monitor with full range drivers that sound amazing that I use in my office. Looking for a setup for my soon to be renovated Living Room area which is a much larger and tougher space to handle. Thanks for responding.
Regards
Yes, that was me.
I also want to try an OB but I also don't want to have any passive crossover on my Lii Fast-10S. The problem I foresee is getting sufficient bass from just a Fast-10S on an OB, which is why I'm looking to use a slot-loaded bass arrangement. I plan to adopt/adapt the Nelson Pass active crossover (available from the DIY Audio store) enabling each driver to have its own power amp. The Fast-10S will have the flea-power SE-OTL amp, unhampered by any passive crossover components and will run almost full range.
Thanks - that sounds like a great setup, please share when its up and running really curious as to how that will sound.
I miss the days when you could walk into an audio shop and actually demo equipment before you buy it (showing my age
. I'll take a look at the active crossover's sounds like a great idea. I agree re; about the passive crossovers. Somehow hearing the Decware Zen Triode SET with the Omega's has me really sold on a simple path without a crossover but I think you are right about the bass. Thanks again - regards and good luck!Steve
for a small OB here's an outdoor graph of Hawthorne's "Silver Iris" 15cx (essentially Eminence's discontinued Beta15CX with change from 38 ounce to 30 ounce ferrite slug to raise Qt to around "1") on a 24" X 36" baffle (plus one triangular side wing on its frame) - you can see the effects of adding 4 ohm resistance to the drive impedance.
with one ohm added, the attenuation around resonance wasn't very much so adding some source impedance can alter the balance to some degree.
with one ohm added, the attenuation around resonance wasn't very much so adding some source impedance can alter the balance to some degree.
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Adding wings or an open back square enclosure to the back side of an OB can get you into the 60Hz region with the 15" Lii. To do better, you can -
- add a subwoofer to the system to assist with low frequencies.
- add a 2nd woofer on the OB to assist with low frequencies.
I'm going to do the 2nd woofer approach. After all, this is a hobby - it's all about cuttin' wood, tweaking electronics, measuring, listening - and rinse / repeat.
I'm going to follow MJK's 18" H frame design, with the current baffle as the center of the "H" structure.
(The hardest part is taking down the units as they are, removing the drivers and getting them into the garage where I can route the cutouts for the 18's. "they're just fine with the sub"... "what if I make a mistake / have an accident / wreck the baffle?"... "what if I cant tune them to be as good as with just the sub, no matter what I try?" There's always the risk of ruining what I have already)
Even when listening through Daphile, with the EQ different than what I posted above using EqualizerAPO, the F15s can still stop me in my tracks at times. They have that attention grabbing sound - apparently even if the frequency response isnt dead on flat. An attribute others have shared regarding Lowther and other brand FR drivers that dont measure so well - but sound great to their owner.
- add a subwoofer to the system to assist with low frequencies.
- add a 2nd woofer on the OB to assist with low frequencies.
I'm going to do the 2nd woofer approach. After all, this is a hobby - it's all about cuttin' wood, tweaking electronics, measuring, listening - and rinse / repeat.
I'm going to follow MJK's 18" H frame design, with the current baffle as the center of the "H" structure.
(The hardest part is taking down the units as they are, removing the drivers and getting them into the garage where I can route the cutouts for the 18's. "they're just fine with the sub"... "what if I make a mistake / have an accident / wreck the baffle?"... "what if I cant tune them to be as good as with just the sub, no matter what I try?" There's always the risk of ruining what I have already)
Even when listening through Daphile, with the EQ different than what I posted above using EqualizerAPO, the F15s can still stop me in my tracks at times. They have that attention grabbing sound - apparently even if the frequency response isnt dead on flat. An attribute others have shared regarding Lowther and other brand FR drivers that dont measure so well - but sound great to their owner.
regarding evsentry3's measurements of fs in the 70's and Qt around 2, that's something like the old small alnico magnet Electrovoice SP15B assuming fs drops somewhat with use.
Lii Audio 15" full range
EV3 - did you jot down the full WT3 parameters including Vas ?
Lii Audio 15" full range
EV3 - did you jot down the full WT3 parameters including Vas ?
Ms F15 has a new partner -
She'll stand by him for a while, perhaps one day kicking him to the curb for one of those 30Hz Fs guys... This ones Fs is ~40 -
A Dayton 75WPC class D amp is in the mail, which fits on the shelf space I have. It's not a sub-specific amp, so I'll have to work out an Xover somewhere in between my DAC and the amps inputs. Or inside the amp itself, if possible.
Pretty much unusable until then. But, things are progressing toward a WAW OB system. Any line level Xover design / source suggestions welcome. Thanks for looking!
She'll stand by him for a while, perhaps one day kicking him to the curb for one of those 30Hz Fs guys... This ones Fs is ~40 -
A Dayton 75WPC class D amp is in the mail, which fits on the shelf space I have. It's not a sub-specific amp, so I'll have to work out an Xover somewhere in between my DAC and the amps inputs. Or inside the amp itself, if possible.
Pretty much unusable until then. But, things are progressing toward a WAW OB system. Any line level Xover design / source suggestions welcome. Thanks for looking!
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The Lii Audio one is probably very good, but the "measured" response seems very smoothed out to me.
I think real life performance is comparable, IE not vastly different. Specs are also a bit similar.
It is possible that the Lii Audio could be a little bit better (cast frame + phase plug), but I get trust issues when I see those super smooth lines.
I think real life performance is comparable, IE not vastly different. Specs are also a bit similar.
It is possible that the Lii Audio could be a little bit better (cast frame + phase plug), but I get trust issues when I see those super smooth lines.
My F15s have now between 45 & 50 hours run in a barrel shape OB like the Decware or Caintuck.
I can compare them with my usual speakers to the push of a button, so the comparison is immediate, not perfect because the placements are obviously different and I use two different amplifiers but I know their distinctive action on my reference speakers.
As such these drivers are quite good but being fixed in an OB the placement is critical.
I could go with this as my prime system, adapting the OB's size to my room and making it thick and heavy.
But I think I am going to try them into a Karlson enclosure if I have the courage.
I am thinking of an enlarged K15, big stuff then ! Yes, if you see the Lii's drawing for these F15 in a vented box, you get something like 290L !!! The K I imagine would be only 210L for both chambers.
Why a K, because I have an excellent experience with these and I am confident on the built (my avatar is a K, really excellent)...just need the courage.
I can compare them with my usual speakers to the push of a button, so the comparison is immediate, not perfect because the placements are obviously different and I use two different amplifiers but I know their distinctive action on my reference speakers.
As such these drivers are quite good but being fixed in an OB the placement is critical.
I could go with this as my prime system, adapting the OB's size to my room and making it thick and heavy.
But I think I am going to try them into a Karlson enclosure if I have the courage.
I am thinking of an enlarged K15, big stuff then ! Yes, if you see the Lii's drawing for these F15 in a vented box, you get something like 290L !!! The K I imagine would be only 210L for both chambers.
Why a K, because I have an excellent experience with these and I am confident on the built (my avatar is a K, really excellent)...just need the courage.
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OK I lied - I did buy the original crossovers for the 18", 4 Ohm Wharfdale drivers. This yielded a 3.3mH inductor and a 110uF cap, for $10 - shipped. Just to have something to hook up, while waiting for the amp. Scrounging through my parts box, the biggest I could make the inductor was 6m and the cap 485u. With a 5 ohm across the inductor, I'm able to get a couple db down at 100Hz - at least in LT spice with a 4 Ohm resistor load. They are simply connected in parallel with the Liis.
The bass is very polite and I'll need the amp to shelve it up a bit to match the Liis efficiency. Drums and bass guitar very fast and fun to listen to and sounding more like a normal speaker as with the sub before. Amp arriving on Saturday, again hope to put a proper passive line level EQ within it at which time the junkbox Xovers will be eliminated. Only a few days more to have to listen to them this way -
The bass is very polite and I'll need the amp to shelve it up a bit to match the Liis efficiency. Drums and bass guitar very fast and fun to listen to and sounding more like a normal speaker as with the sub before. Amp arriving on Saturday, again hope to put a proper passive line level EQ within it at which time the junkbox Xovers will be eliminated. Only a few days more to have to listen to them this way -
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Now running separate amps for the Lii and her 18" partner. With the 100Hz passive xover and being able to shelve the bass output up to meet the Lii, things are sounding pretty good between them.
The new amp uses op-amps to provide a rear panel set and forget bass and treble controls. I'll take a stab at reverse engineering those to provide the proper filtering for using the 18s in an OB. Hopefully without destroying the amp in the process - it's all surface mount components! I'm used to working point-to-point in a tube amp...
Listening to my older stuff they are beginning to remind me of my Altec Valencias and Polk SDAs from a past life - but without the horn squalks or mid band Xover phase distortion!
The new amp uses op-amps to provide a rear panel set and forget bass and treble controls. I'll take a stab at reverse engineering those to provide the proper filtering for using the 18s in an OB. Hopefully without destroying the amp in the process - it's all surface mount components! I'm used to working point-to-point in a tube amp...
Listening to my older stuff they are beginning to remind me of my Altec Valencias and Polk SDAs from a past life - but without the horn squalks or mid band Xover phase distortion!
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