I would think there are more advantages to getting the bass out of the FR than there are "purists" benifits to not having a subwoofer DEPENDING on the music and volume. Perhaps with light music having the bass in the FR is ok. I know the FRs at Dave's I've heard didn't sound strained by not having subs. Funny thing, he had about 3 or 4 subs stacked up in the corner NOT hooked up 😛 And the volume level was quite alright by me. Still, I think I'll always require bass support in some form.
If I could afford it, I wanted to use this: http://www.solen.ca/pdf/sb/sb34nrx756.pdf
Paired with the FR88EXs you sold me actively crossed around 300hz. I think that would make a 20 to 20 two way. Sensitivity would have been decent too.
That said, that is really bordering a Full Range with Subs rather than a FAST. Those SBs are pretty big. Perhaps side mounted and they would be pretty nice. Maybe mated with a little bigger FR even.
Of course there are advantages but the disadvantage of have speakers the size of chest freezers just seems to outweigh everything else.
Lets call it a woofer. The biggest gains with a helper woofer are ironically in the mid/top.
dave
The answer is yes, but then the question here becomes how are you going to limit the LF going to your FR driver?
You can get a plate amp with a high-passed out on it. I used one for a while. With little 3-in FR drivers I felt like it was worth the hit in sound quality. But it did have its own problems.
Now I have a cheap little active cross box. It's much better! But there are those who would turn their noses up at such a simple opamp setup. They're probably not wrong. You could go with a passive line-level setup (search PLLXO around here). Some would want a fully discreet active cross box. Some would want tubes to do it. Others would want to do it digitally. Some have used a small sealed box to limit response (tho not amp output).
I think managing the bass to the FR driver is key. Figuring out how to do it in your own system is left as an exercise for the reader...
That is what I do.
Subwoofers do not have "quick transients." Crossing over at 80Hz rules out "quick" anyway.
Good thoughts here. Thanks.
Personally, I use a AV receiver with an active subwoofer XO built in. I know, I know, but it's a good receiver (sherwood newcastle) and has excellent sound quality. Makes manipulating the digital signal domain so easy. XO frequency and subwoofer level is a snap. Speaker level balance a snap. Etc. Not to mention I'd need one for my movie experience anyways.
Active is good! In a setup for an office, I used a Richter Scale III (no longer in production). At home I am using the crossover in a Rotel home theater preamp.
The high-out in the sub plate amps I have seen is lousy. They use iron core inductors and cross over too high.
indeed, with appropriately chosen XO points, not only can LF extension be "seamless", but the most notable improvement will likely be lower distortion and increased dynamics of the wide-band section
Partly.
since by its very nature, a full range driver will always suffer SOME IMD, since it is reproducing such a large range. just like our ears will do the same, at sufficient volumes. That being said, many tweeters also suffer with IMD to an equal extent. even so a sub will suffer IMD too, if you play large organ music, or even just play a large organ, and hit a dischordant note by mistake....also any AUDIBLE THD will increase the perceived or actual IMD, any guitar player that has modded his own fuzzbox with silicon diodes will know this. This is probably (IMO only perhaps) the reason many tube amp-o-philes, prefer the sound of valves. the even harmonics produced are less annoying and generally IME do not produce the same level of resultant IMD as from the HARD clipping of a SS amp, even at miniscule levels. probably why tube amps are still so popular with musicians.
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I'm really gratified and grateful for all the activity to my basic newbie question.
1. For controlling frequency (high and low pass), I'll probably use something like the miniDSP. Specs seem good and doesn't seem to impact the tone audibly other than the cutoff.
2. Pardon my ignorance but what is FAST?
Thanks,
UL
1. For controlling frequency (high and low pass), I'll probably use something like the miniDSP. Specs seem good and doesn't seem to impact the tone audibly other than the cutoff.
2. Pardon my ignorance but what is FAST?
Thanks,
UL
Ooh, I'd like to answer that because I'm quite excited about it.
It's a Full range AssiSTed, or Full Range with Subwoofer Technology. I kinda think the acronym is bad, but essentially it's a full range with the bottom frequencies handled by a woofer(s). Here's an example of one I'm working on:
An externally hosted image should be here but it was not working when we last tested it.
I'll end up crossing that around 300hz before the fountek FR88 runs into any possible excusion limitations and the 6.5" woofers will take over. A part of the design (and most FAST designs) includes using the woofer(s) to compensate for baffle step as well.
Hi Fellas,
I've been asked to write 2 articles on designing and making drivers for Klang and Ton in Germany and an Audio group in China. I cover some of issues relating to the design and operation of LF drivers. Here's part of a draft section from one of my papers:
Its allot easier to build drivers for split loads (woofer, mids and tweets). Commercially, the build tolerances for limited range emitters are wider making it easier to design for greater mechanical loads. Building for greater power-handling often helps extends service life. A well-made woofer could potentially have an operating capacity in excess of 20 years if operated under nominal load conditions. However, many woofer designs have significant mechanical and acoustic output limitations. To withstand greater driven loads, a woofer's power-train has to be made stronger. Its cone and power-train will likely have significant mass, restricting its ability to micro-resonate; A feature needed for accurately emitting LF musical detail. Added to this condition is another mechanical design challenge, that of controlling driven inertia. Trying to get a heavier power-train to oscillate efficiently with minimal linear irregularity is a major challenge. Therefore, many woofers are effectively mass-inertia compromised. In particular, many sub-woofers are so over-mass compromised that they are only capable of emitting prime frequencies; Their cones incapable of delivering the resonance patterns necessary for emitting actual musical data. Therefore many LF drivers are effectively “noise” or “effect generators” rather than “audio” drivers in the original sense of the form and should be categorised accordingly.
I should point out that I've been asked these articles from the original "High-Fidelity" perspective. Thats an increasingly narrow perspective as more of us play music with artificial content or have compressed reproductions. In these situations, subs may potentially provide output appropriate to the source material.
All the same, simply adding subs to care of the LF output doesn't automatically mean you'll get better overall sound quality. Its worth doing allot of research on a sub's performance before purchasing. As a guide, try to find a unit with the lowest moving mass. Or take another look at your future projects as it may be possible to satisfy your LF needs from alternative designs.
Cheers
Mark.
I've been asked to write 2 articles on designing and making drivers for Klang and Ton in Germany and an Audio group in China. I cover some of issues relating to the design and operation of LF drivers. Here's part of a draft section from one of my papers:
Its allot easier to build drivers for split loads (woofer, mids and tweets). Commercially, the build tolerances for limited range emitters are wider making it easier to design for greater mechanical loads. Building for greater power-handling often helps extends service life. A well-made woofer could potentially have an operating capacity in excess of 20 years if operated under nominal load conditions. However, many woofer designs have significant mechanical and acoustic output limitations. To withstand greater driven loads, a woofer's power-train has to be made stronger. Its cone and power-train will likely have significant mass, restricting its ability to micro-resonate; A feature needed for accurately emitting LF musical detail. Added to this condition is another mechanical design challenge, that of controlling driven inertia. Trying to get a heavier power-train to oscillate efficiently with minimal linear irregularity is a major challenge. Therefore, many woofers are effectively mass-inertia compromised. In particular, many sub-woofers are so over-mass compromised that they are only capable of emitting prime frequencies; Their cones incapable of delivering the resonance patterns necessary for emitting actual musical data. Therefore many LF drivers are effectively “noise” or “effect generators” rather than “audio” drivers in the original sense of the form and should be categorised accordingly.
I should point out that I've been asked these articles from the original "High-Fidelity" perspective. Thats an increasingly narrow perspective as more of us play music with artificial content or have compressed reproductions. In these situations, subs may potentially provide output appropriate to the source material.
All the same, simply adding subs to care of the LF output doesn't automatically mean you'll get better overall sound quality. Its worth doing allot of research on a sub's performance before purchasing. As a guide, try to find a unit with the lowest moving mass. Or take another look at your future projects as it may be possible to satisfy your LF needs from alternative designs.
Cheers
Mark.
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I use a full range on an open baffle run wide open with an 80hz f-mod on a 12" woofer (see avatar, for now anyway).
Intelligibility is superior to either my klipsch 8" 2-way crosed 18db near 2khz, or my 15's plus horn crossed 24db LR at 750hz. But I miss my double 15 bass, and sometimes I want for a super tweeter.
My buddy said "yea people play with full ranges untill they want a little more full range."
You give some, you take some, you juggle compromises with priorities and you come up with what makes you happy. For me, for now, intelligibility is a priority.
Norman
Intelligibility is superior to either my klipsch 8" 2-way crosed 18db near 2khz, or my 15's plus horn crossed 24db LR at 750hz. But I miss my double 15 bass, and sometimes I want for a super tweeter.
My buddy said "yea people play with full ranges untill they want a little more full range."
You give some, you take some, you juggle compromises with priorities and you come up with what makes you happy. For me, for now, intelligibility is a priority.
Norman
Good point Mark (MA guy)
I have a 12" subwoofer and it works very well for the low stuff. Heavy cone, long Xmax sort of thing. Built a isobaric 15" subwoofer from a pair of Cerwin Vega pro sound speakers (W15P) To get the bass extension down, I used an 18 inch passive radiator.
The subwoofers sound distinctly different. Sure, the push-pull setup helps with distortion but the pro sound woofers have a more musical sound that blends with the main speakers better. The dedicated 12 inch has more of a one or two note sound. Could be that the woofers produce all the sound heard until 30 Hz when the passive wakes up--the dedicated 12 inch sub is ported so it could be that. Maybe the much lighter cones and shorter Xmax help? Either way, I enjoy the odd ball I built with the pro woofers in it more than the 12" hell hound.
Always figured full ranges would sound odd if the cone was getting close to Xmax and still trying to produce the 10K to 20K octave. Since a lot of "helper woofers" I've seen are short Xmax pro sound woofers, I'm assuming there is something to this. Either that or the pro sound stuff works better, handles more power and is much louder to match the FRs?
I have a 12" subwoofer and it works very well for the low stuff. Heavy cone, long Xmax sort of thing. Built a isobaric 15" subwoofer from a pair of Cerwin Vega pro sound speakers (W15P) To get the bass extension down, I used an 18 inch passive radiator.
The subwoofers sound distinctly different. Sure, the push-pull setup helps with distortion but the pro sound woofers have a more musical sound that blends with the main speakers better. The dedicated 12 inch has more of a one or two note sound. Could be that the woofers produce all the sound heard until 30 Hz when the passive wakes up--the dedicated 12 inch sub is ported so it could be that. Maybe the much lighter cones and shorter Xmax help? Either way, I enjoy the odd ball I built with the pro woofers in it more than the 12" hell hound.
Always figured full ranges would sound odd if the cone was getting close to Xmax and still trying to produce the 10K to 20K octave. Since a lot of "helper woofers" I've seen are short Xmax pro sound woofers, I'm assuming there is something to this. Either that or the pro sound stuff works better, handles more power and is much louder to match the FRs?
Eleven years ago, it was explained to me as Fullrange And Subwoofer Technology, which doesn't seem such a far stretch acronym wise.
Hi
I'm using a pair of A126 and a sub with a miniDSP+miniDigi combo.
It´s the best sounding sub integration I've listened to so far. The 2WaySUBadvanced plugin and the REW room tuning is a superb tool for optimizing the sub respons.
XO for the low pass is 80hz 48db, and now the most important thing: highpass goes from 45hz 48db.
I think it´s necessary to overlap the fullrange, you still want to produce some bass from your fullrange (especially horndriven as my FE126/A126) and cutoff the lowest part). Another good feature with the plugin is that you can set the delay for each channel. In the end a pretty smart way of blending fullrange/sub woofer without to much tweaking.
Anders
I'm using a pair of A126 and a sub with a miniDSP+miniDigi combo.
It´s the best sounding sub integration I've listened to so far. The 2WaySUBadvanced plugin and the REW room tuning is a superb tool for optimizing the sub respons.
XO for the low pass is 80hz 48db, and now the most important thing: highpass goes from 45hz 48db.
I think it´s necessary to overlap the fullrange, you still want to produce some bass from your fullrange (especially horndriven as my FE126/A126) and cutoff the lowest part). Another good feature with the plugin is that you can set the delay for each channel. In the end a pretty smart way of blending fullrange/sub woofer without to much tweaking.
Anders
I assume you mean 48db per octive. you might need that much overlapping with such a sharp crossover (remember also that a horn automatically has a sharp slope at LF cut off) I really don't think you're getting down to 45hz with Fe126s though unless your horn is the size of a football stadium. The FE126 has an Fs of 70hz and very limited Xmax so your high pass filter isn't doing anything for your integration but instead merely limits subsonic excersion from the driver.
Thank´s for the explanation, so a steep filter like 48dB may require some overlapping. I´ll guess your right; A126 is not capable to reach 45Hz but I´m quite sure that 50Hz is possible. I´m fine tuning by ear and 50Hz was a little to high so that´s the reason for choosing 45Hz.
Anyway, many miniDSP users are suggesting 48dB filtering, when you use advanced Biquading filters.
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