I have an acquaintance who has used both the Betsy and A.N. Super Cast 8 in his OB. He prefers the A.N. though not by a large margin. The Betsy 's price is certainly appealing. However if I go the 8 inch route I may just roll the dice on the Audio Nirvanas and be done with it.
cubdog
Yup the AN should produce very good results as well. Once you get it all dialed in I think you will be very pleased with your efforts.
I'm still imprinted by the loudspeaker/enclosure practices of 40 years ago, when I started building boxes. So: how does the 15a stand OB application plus EQ without damage? Did Eminence design for xlim beyond what the wimpy motor can do? Or is the target SPL at girl with guitar level? I do not enjoy the rapping and popping sounds of overdriven woofers.
On topic, I also vote for the smaller FR.
On topic, I also vote for the smaller FR.
Not sure really. It may be just that the size of the driver(s) move a lot of air and dont need to move alot to play higher volumes. I have turned mine up pretty loud with rock music and never had any issues at all with excursion limits. They actually perform quite well on OB in spite of the small magnets.
That is why they are 97dB efficient drivers - they don't need to move a lot. 3.8 mm xmax is quite a lot for a driver that is this efficient - and the xmech is much larger at 8.4mm, so you won't hear the clicking and rubbing of over driven cones.
>>> Warning: It is hard to stop...
Ain't that the truth!
Since my divorce started about three years ago (and counting!) I've taken a step back and looked at all the drivers I purchased over the years that are sitting unused. Fortunately, none were terribly expensive. Interestingly enough, the drivers I'm listening to now are the most expensive ones I've bought - TB 1808 in living room and Fostex 168z in bedroom. I just tucked the Eminence 12lta's away to swap in the 1808. I may dive into my stash of cheapies soon... old Radio Shack drivers and 69 cent gems waiting to play. When I get back on my feet I may buy something by Mark Audio otherwise, I'm pretty satiated. I also want another longboard.
Ain't that the truth!
Since my divorce started about three years ago (and counting!) I've taken a step back and looked at all the drivers I purchased over the years that are sitting unused. Fortunately, none were terribly expensive. Interestingly enough, the drivers I'm listening to now are the most expensive ones I've bought - TB 1808 in living room and Fostex 168z in bedroom. I just tucked the Eminence 12lta's away to swap in the 1808. I may dive into my stash of cheapies soon... old Radio Shack drivers and 69 cent gems waiting to play. When I get back on my feet I may buy something by Mark Audio otherwise, I'm pretty satiated. I also want another longboard.
Thanks again for all the information guys.
So now I have another question. Surprise.😉
How much is gained by using two of the Eminence Alpha 15s per side as opposed to one? Will their be a noticeable improvement in bass quality? I'm not a bass head but I like quality bass, tight, with no distortion. If I could achieve the same results using one Alpha 15 or two 12 or 10 in woofers, per side, that would be great. From and aesthetic point of view it would surely look better, at least, to my eye. Thoughts?
cubdog
So now I have another question. Surprise.😉
How much is gained by using two of the Eminence Alpha 15s per side as opposed to one? Will their be a noticeable improvement in bass quality? I'm not a bass head but I like quality bass, tight, with no distortion. If I could achieve the same results using one Alpha 15 or two 12 or 10 in woofers, per side, that would be great. From and aesthetic point of view it would surely look better, at least, to my eye. Thoughts?
cubdog
My experience has been that doubling drivers reduces harmonic distortion for same SPL. Also you have higher ultimate SPL capability. If you have the room two 15 in woofers - go for it.
It adds 6 dB of dynamic headroom, equivalent to halving the excursion required and since if you can see a driver moving from the listening position [Lp], it's already distorting [usually audibly].............
Overall bass quality is mostly a function of proper blending to the mids/HF where its harmonic structure that defines its 'PRaT' [pace, rhythm & timing] are reproduced, so getting the phase matched close enough through the XO BW is essential to a high sound quality [SQ].
GM
From this I infer two woofers properly integrated, via the crossover, can only improve the quality of the bass. Like I said my goal isn't loud, pounding bass but clean defined bass.
I'm curious if anyone feels, and why, using two woofer per side is a bad thing? I'm beginning to think, that with speaker design, tradeoffs are just part of the game.
cubdog
Correct, though obviously if you only listen to highly compressed, BW limited music at Muzak level SPLs as some apt., condo dwellers are forced to do, then probably won’t be worth the extra cost and can probably get by with a single 12”/channel.
If you occasionally want to listen at piano bar levels as I do though, you’ll need at least dual 15”/channel and depending on in-room conditions could need four/channel with two rolled off in an OB app. At this point, mounting the ‘FR’ driver in the center of a four square layout to mimic a really large point source becomes desirable.
It only becomes a bad 'thing' when the acoustic centers are too far apart to sound as one at the LP. As the ‘FR’ driver shrinks in size then, the usable XO point rises and the acoustic c-t-c spacing shrinks with it.
Up to a point then, mounting dual woofers horizontally opposed is preferred since it both minimizes the c-t-c spacing plus increases horizontal directivity to a lower frequency same as a horn does with the trade-off being a taller vertical soundstage.
Correct, sound systems define design trade-offs and won’t be solved until we can figure out how to get a pinhead size point source to radiate into pi space [omni] at 1 acoustic watt [120 dB] at vanishingly low distortion, i.e. truly ‘magical’.
Folks often gravitate to OBs because they seem so simple and offer the least ‘colored’ presentation, but the reality is that they are the most complex to properly implement in a bounded space, especially if covering a recording’s entire signal BW is desired and why I long ago concluded that acoustically large, low tuned cabs with relatively wide baffles was the best way overall to ‘have my cake and eat it too’.
GM
If you occasionally want to listen at piano bar levels as I do though, you’ll need at least dual 15”/channel and depending on in-room conditions could need four/channel with two rolled off in an OB app. At this point, mounting the ‘FR’ driver in the center of a four square layout to mimic a really large point source becomes desirable.
It only becomes a bad 'thing' when the acoustic centers are too far apart to sound as one at the LP. As the ‘FR’ driver shrinks in size then, the usable XO point rises and the acoustic c-t-c spacing shrinks with it.
Up to a point then, mounting dual woofers horizontally opposed is preferred since it both minimizes the c-t-c spacing plus increases horizontal directivity to a lower frequency same as a horn does with the trade-off being a taller vertical soundstage.
Correct, sound systems define design trade-offs and won’t be solved until we can figure out how to get a pinhead size point source to radiate into pi space [omni] at 1 acoustic watt [120 dB] at vanishingly low distortion, i.e. truly ‘magical’.
Folks often gravitate to OBs because they seem so simple and offer the least ‘colored’ presentation, but the reality is that they are the most complex to properly implement in a bounded space, especially if covering a recording’s entire signal BW is desired and why I long ago concluded that acoustically large, low tuned cabs with relatively wide baffles was the best way overall to ‘have my cake and eat it too’.
GM
>>> ... and why I long ago concluded that acoustically large, low tuned cabs with relatively wide baffles was the best way overall to ‘have my cake and eat it too’.
I go thru phases. Currently I am very into the open baffle thing - full range with bass support. I'm usually listening in smaller spaces (tho I have been enjoying a temporary large living room). Clearly, smaller rooms have advantages when it comes filling them with sound. One 15" driver seems to suit my situation with more than enough headroom to spare. Regarding highly efficient drivers (like the Eminence 12lta - rated at 97db) just one Alpha 15 in an H-frame barely produces enough satisfying bass output to provide a balanced sound. Swapping out the 12lta for the TB 1808 - rated at 93db - produces a more balanced sound in the larger room.
Just an estimate, but drivers with efficiency ratings of 92 and below work better with one Alpha 15 per side... anything above that would sound better with two.
As for the OP, I can't see how a consensus can be formed on the best 8" woofer. There are a lot of 'bests' and many good choices. Unless it's too sibilant, I usually enjoy whatever's playing music.
I go thru phases. Currently I am very into the open baffle thing - full range with bass support. I'm usually listening in smaller spaces (tho I have been enjoying a temporary large living room). Clearly, smaller rooms have advantages when it comes filling them with sound. One 15" driver seems to suit my situation with more than enough headroom to spare. Regarding highly efficient drivers (like the Eminence 12lta - rated at 97db) just one Alpha 15 in an H-frame barely produces enough satisfying bass output to provide a balanced sound. Swapping out the 12lta for the TB 1808 - rated at 93db - produces a more balanced sound in the larger room.
Just an estimate, but drivers with efficiency ratings of 92 and below work better with one Alpha 15 per side... anything above that would sound better with two.
As for the OP, I can't see how a consensus can be formed on the best 8" woofer. There are a lot of 'bests' and many good choices. Unless it's too sibilant, I usually enjoy whatever's playing music.
It can result in a decrease in "impact" or that tactile sensation, this is because excursion is lowered.
Most everything else is positive however, and particularly in a "simple" context - the combing from the two woofers (and listening at an angle well off of the center between the woofers vertically), can enhance the "roll-off" or "low-pass" nature of the higher freq.s (reducing them acoustically). This helps counter the "high-pass" nature of the open baffle loss at lower freq.s.
Additionally you'll get both acoustic and voltage gain with two woofers wired in parallel, PLUS the lower impedance by wiring in parallel (target 4 ohms) allows for a smaller series inductor for the low-pass section.
The ideal is to only use *one* inductor in series with the two woofers to form the eq. and low-pass filter of the woofers.
Shavano Music Online - First Order Crossover Networks
(note: no series capacitor as a high-pass filter for the fullrange/tweeter as shown on this website.)
Here is a grouping a relatively high inductance and low resistance inductors at a good price (select "solid core inductors" on the left of the page):
http://www.parts-express.com/brand/jantzen-audio/306
The lower the resistance for your required inductance value - generally the better, but also the more expensive.
Of course the above portion on crossover design is with respect to a passive crossover. IF you are going with an active crossover and necessarily bi-amping then disregard this.
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coaxial driver 6.5 inch
Could this be an interesting coaxial driver for an OB?
Amazon.com : Clarion SRG1621R 6 1/2-Inch Coaxial Speaker System : Vehicle Speakers : Car Electronics
Could this be an interesting coaxial driver for an OB?
Amazon.com : Clarion SRG1621R 6 1/2-Inch Coaxial Speaker System : Vehicle Speakers : Car Electronics
Don't know about 'interesting', but back when I was making a lot of inexpensive speakers for friends, co-workers, etc. 40-45 yrs ago, using high Qt car audio speakers in general and coaxials in particular was the obvious choice for me since they were cheap and worked well in damped open back 'bookshelf' and TL tower designs, so OB would be an option and see no reason why they still wouldn't be the obvious choice except that they now are typically 4 ohm Vs the 8-16 ohm back then.
Don't know about now, but back then, Clarion, Sony were the best 'bang-buck' to my ears. Later, it was Infinity.
GM
Don't know about now, but back then, Clarion, Sony were the best 'bang-buck' to my ears. Later, it was Infinity.
GM
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