You're welcome!
What happens when an object is inserted under the cab, such as shock absorbing feet?
I was both tacitly confirming your assertion for what they do plus adding to it.Not suggesting, stating a fact AFAIK; again, we're always trading efficiency for BW, so to get a lower tuning frequency we have to shift acoustic efficiency down from higher up. This summed driver/cab efficiency has a more gradual roll off over a wider BW that we humans perceive as a better transient response and it shows up as a better impulse response too, but actual driver loading is acoustically less efficient because we have over-damped it, hence can't handle as much power down low = lower acoustic deficiency.
Note that the driver is already over-damped, i.e. Its Qts is very low, well below the transient perfect/critically [0.5 Qt] 1st order slope and way below the max flat [0.707] 2nd order slope, which in some old docs are listed as critically damped also. Over-damping the cab too isn't my idea of improving damping of a driver that's already over-damped since this can create an under-damped ['boomy'/'one note'] alignment.
To optimally damp the driver one must always tune the cab to the driver's actual Fs, which is desirable for max bass output if using a high output impedance tube amp. With highly damped amps, one can tune the cab wherever it performs the best overall for the intended app.
To improve driver damping and acoustic efficiency above Fs like I understand you to want requires tuning it higher than a stock A7, reducing its usable gain BW, which will worsen perceived transient response/increase any perceived 'boominess' as the trade-off, so again, to get a major gain over ~45-200 Hz requires a large rear loaded horn [BLH].
Note that when the baffle boards are removed, the so-called reflex cab is actually a crude two segment BLH and some folks use them this way to get some extra acoustic efficiency to fill in below the front horn's roll off, but again, transient response suffers if not BW limited to protect the driver, requiring a separate woofer system to fill in the bottom ~2.5 - 3 octaves.
GM
Bruce,
My sense is that you may be hearing mostly the effect of LESS rear radiation at "undesirable" frequencies being passed out the the "hole in the box" aka the "port", more properly the reflex opening.
That is why I chose to use the tuning method shown in my images above, that consist of tuned ports of some length computed by a simulator and tuned in empirically. This alone reduces the higher frequency energy passed out of the box.
In addition I used significant absorption on the walls of the interior. At bass frequencies, it's doing surprisingly little but at even 125Hz, it's doing quite a bit. The result is the attenuation of higher frequency energy both out through the ports (even if the classic "reflex hole" is used) and reflected back as out of phase energy through the paper cone. A benefit regardless.
It's entirely unclear to me that being "married" to the old Altec drivers given the number of very good, high performance pro 15" drivers with superior motor designs and that giving the ability to find more optimal T/S parameters for the given box volume is still the best way to go. As noted the Qt is super low, and the VAS (not mentioned yet) is really too great to tune lower in this volume.
The other factor is "room lift" which depends on the room's volume, layout, and where the speakers are placed - in some cases this can boost the bass quite a bit.
The Klipsh Corner Horns were infamous for their reliance upon the room dimension and shape. The right room, they were amazing on the bottom, most rooms? Not so great.
My sense is that you may be hearing mostly the effect of LESS rear radiation at "undesirable" frequencies being passed out the the "hole in the box" aka the "port", more properly the reflex opening.
That is why I chose to use the tuning method shown in my images above, that consist of tuned ports of some length computed by a simulator and tuned in empirically. This alone reduces the higher frequency energy passed out of the box.
In addition I used significant absorption on the walls of the interior. At bass frequencies, it's doing surprisingly little but at even 125Hz, it's doing quite a bit. The result is the attenuation of higher frequency energy both out through the ports (even if the classic "reflex hole" is used) and reflected back as out of phase energy through the paper cone. A benefit regardless.
It's entirely unclear to me that being "married" to the old Altec drivers given the number of very good, high performance pro 15" drivers with superior motor designs and that giving the ability to find more optimal T/S parameters for the given box volume is still the best way to go. As noted the Qt is super low, and the VAS (not mentioned yet) is really too great to tune lower in this volume.
The other factor is "room lift" which depends on the room's volume, layout, and where the speakers are placed - in some cases this can boost the bass quite a bit.
The Klipsh Corner Horns were infamous for their reliance upon the room dimension and shape. The right room, they were amazing on the bottom, most rooms? Not so great.
You're welcome!
What happens when an object is inserted under the cab, such as shock absorbing feet?
Not suggesting, stating a fact AFAIK; again, we're always trading efficiency for BW, so to get a lower tuning frequency we have to shift acoustic efficiency down from higher up. This summed driver/cab efficiency has a more gradual roll off over a wider BW that we humans perceive as a better transient response and it shows up as a better impulse response too, but actual driver loading is acoustically less efficient because we have over-damped it, hence can't handle as much power down low = lower acoustic deficiency.
Note that the driver is already over-damped, i.e. Its Qts is very low, well below the transient perfect/critically [0.5 Qt] 1st order slope and way below the max flat [0.707] 2nd order slope, which in some old docs are listed as critically damped also. Over-damping the cab too isn't my idea of improving damping of a driver that's already over-damped since this can create an under-damped ['boomy'/'one note'] alignment.
To optimally damp the driver one must always tune the cab to the driver's actual Fs, which is desirable for max bass output if using a high output impedance tube amp. With highly damped amps, one can tune the cab wherever it performs the best overall for the intended app.
To improve driver damping and acoustic efficiency above Fs like I understand you to want requires tuning it higher than a stock A7, reducing its usable gain BW, which will worsen perceived transient response/increase any perceived 'boominess' as the trade-off, so again, to get a major gain over ~45-200 Hz requires a large rear loaded horn [BLH].
Note that when the baffle boards are removed, the so-called reflex cab is actually a crude two segment BLH and some folks use them this way to get some extra acoustic efficiency to fill in below the front horn's roll off, but again, transient response suffers if not BW limited to protect the driver, requiring a separate woofer system to fill in the bottom ~2.5 - 3 octaves.
GM
Hi GM,
Ahhhhhhhhhhhh, I get it. Thanks a million for the clarification! And thank you for the clarification re the shock absorbing feet Mr. Hiraga had mounted on the bottom of his A-5s. You, Pano, Cal, Dave, and Bear, have been incredibly helpful and patient with me as we worked through this whole reflex port issue, and how it impacts the mid-bass and bass of my A-5s. Very much appreciated!
Once again this proves that there is no free lunch when it comes to all things audio...….....and I assumed the reduction in reflex port area would be a guaranteed free lunch.
My amplifiers are single-ended WE-300Bs with zero global voltage feedback, and as such they have a relatively high output impedance, so their damping effect on the woofer is probably fairly limited, when compared to modern solid-state amps.
You know, at the end of the day, and with the 80 square inch reflex port I had installed, the speaker just doesn't sound right to me. As Pano had correctly stated in an earlier post, listening to my A-5s with the Hiraga crossover network for the past 25 years in the stock configuration (210 square inch reflex port area), may have indeed prejudiced my listening to the sound with the reduced port area. I always marveled at the very open sound my A-5s had, and that sense of openness and speed in the mid-bass seems to be gone now. I was listening to my system this evening for the last hour; I had to turn it off, as the sound was just not exciting like it used to be. That was never the case with the stock port opening, so I know that something was wrong here. And we are all listening to and for different things with our hi-fi systems.
Perhaps the guys who have had much success with the reduced area reflex port are taking the same approach as Bear did; bi-amping the system and using active filtering, EQ, and crossovers to achieve the desired acoustic response and most pleasing sonics. I am not sure, but perhaps Pano is taking this course as well.
I have seen so many examples on the Internet where fellow A-5 and A-7 users have raved about the effect of reducing the reflex port area, but I guess I don't get it. There was one fellow who did not like the sound of the system with the reduced port area, and he thought it was a big mistake in his system. Maybe his and my listening tastes are aligned here.
I'll give it a few more days, but if I can't accept the sonic trade-off of the 80 square inch reflex port, it is a simple matter for me to go back to the stock port.
Best Regards to all of you guys!
Bruce
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Bruce,
How about some MDF, some PVC pipe or carboard tubing from a carpet store, and make a "proper" tuned port at the frequency of your choice??
Or any similar method...
It's critical to understand that if the port length is held constant (the thickness of the wood in this case) and the area is varied, the
tuning frequency is being changed - it's not just that being a different size lets a different amount of sound out.
If you wanted to hold the tuning frequency the same, when the size of the reflex cut out is changed, the depth of the wood (length of the port) would need to change as well.
As I mentioned in private emails, get thee a freeware "bass response" and see what the curves look like... there's no reason to have to guess about these things anymore.
How about some MDF, some PVC pipe or carboard tubing from a carpet store, and make a "proper" tuned port at the frequency of your choice??
Or any similar method...
It's critical to understand that if the port length is held constant (the thickness of the wood in this case) and the area is varied, the
tuning frequency is being changed - it's not just that being a different size lets a different amount of sound out.
If you wanted to hold the tuning frequency the same, when the size of the reflex cut out is changed, the depth of the wood (length of the port) would need to change as well.
As I mentioned in private emails, get thee a freeware "bass response" and see what the curves look like... there's no reason to have to guess about these things anymore.
In asnwer to your text in bold above, no. It's not rolled off low bass, it's actually more low bass and a lack of the peak just above roll off. That's what I measured and that's what I heard, the two agree. In general I find a peak around 70Hz to add warmth to the bass and can be enjoyable. My stock A-7 was like that, a hump circa 60-70 Hz and nothing below that. It sounded full and plump, but not realsitic. Reducing the port area killed the peak and extended the low end response.
That being said, the range covered by the short bass horn will always be more pronounced than the lower ranges, because of the horn and the baffle step. I fixed that by moving the woofer low-pass down a bit, and using some EQ.
I can certainly understand that if you've been listening to and liking the cabinet for 25 years, that lack of a bass peak is going to sound lean. And of course, your room and room placement will play a role. If you can easily change the port size, it's worth measureing and also listening to muisc with good bass content. A lot of muisc rolls off down there, so you have to pick carefully.
That being said, the range covered by the short bass horn will always be more pronounced than the lower ranges, because of the horn and the baffle step. I fixed that by moving the woofer low-pass down a bit, and using some EQ.
I can certainly understand that if you've been listening to and liking the cabinet for 25 years, that lack of a bass peak is going to sound lean. And of course, your room and room placement will play a role. If you can easily change the port size, it's worth measureing and also listening to muisc with good bass content. A lot of muisc rolls off down there, so you have to pick carefully.
Thanks very much, Pano and Bear!
I am a strong believer in listening to any kind of a change for a reasonably extended period of time, and honestly, I have not given the reduced area reflex port modification a serious enough listen. I've been very busy around the outside of our house now that the really warm weather has arrived (cleaning the decks, windows, you get the picture.....), and the bulk of this should be done later this week. I will then really give the speakers a serious listen with some decent program material having a lot of deep bass content, and take it from there.
Pano, I guess you are using active EQ to further sweeten and enhance the low bass performance. I have no way of doing this, and my personal feeling and philosophy is to refrain from doing this within my system. I am suspect as to the artifacts and sonic degradation active EQ may contribute to the sound of my system, and as you can probably surmise, I take a purist, Zen-like approach to the electronics I use here.
Correcting the frequency response anomalies from the HF horn were easy with the Hiraga network. What you, Bear, and GM have clearly stated about the A-5 is correct; there are really two separate issues that have to be addressed independently aside from the HF horn response; the short horn, and the lower acoustic output bass reflex section relative to the short horn. The HF horn and the short horn are essentially matched to each other by virtue of the Hiraga HF section, but the reduced acoustic output of the bass reflex mode is the real issue here, and the only way I see around it is to add active EQ to the woofer, and the proper tuning of the bass enclosure.
As I said yesterday, there is no free lunch in all things audio...……..
Guys, your guidance and patience here has been most appreciated. I'll be in touch after I give everything a more serious listen.
All the Best,
Bruce
I am a strong believer in listening to any kind of a change for a reasonably extended period of time, and honestly, I have not given the reduced area reflex port modification a serious enough listen. I've been very busy around the outside of our house now that the really warm weather has arrived (cleaning the decks, windows, you get the picture.....), and the bulk of this should be done later this week. I will then really give the speakers a serious listen with some decent program material having a lot of deep bass content, and take it from there.
Pano, I guess you are using active EQ to further sweeten and enhance the low bass performance. I have no way of doing this, and my personal feeling and philosophy is to refrain from doing this within my system. I am suspect as to the artifacts and sonic degradation active EQ may contribute to the sound of my system, and as you can probably surmise, I take a purist, Zen-like approach to the electronics I use here.
Correcting the frequency response anomalies from the HF horn were easy with the Hiraga network. What you, Bear, and GM have clearly stated about the A-5 is correct; there are really two separate issues that have to be addressed independently aside from the HF horn response; the short horn, and the lower acoustic output bass reflex section relative to the short horn. The HF horn and the short horn are essentially matched to each other by virtue of the Hiraga HF section, but the reduced acoustic output of the bass reflex mode is the real issue here, and the only way I see around it is to add active EQ to the woofer, and the proper tuning of the bass enclosure.
As I said yesterday, there is no free lunch in all things audio...……..
Guys, your guidance and patience here has been most appreciated. I'll be in touch after I give everything a more serious listen.
All the Best,
Bruce
Greets!
AFAIK, there's no surviving pioneering Altec engineers, only some who came to work long after these systems were designed [circa 1941 for the 'A' series and circa 1947 for the A800] and none AFAIK post on any forums or otherwise available to the general public to 'pick their brains'.
That said, there's plenty of folks that knows at least some of the history and fully understand the 'physics of the situation', so these designs hold no secrets AFAIK as their 'bones' were picked clean as soon as they became available by RCA's Harry Olson and then improved upon. You want a superior performing A5/A7? Restore/replicate his LC-9A with original, or better still, modern drivers. Ditto his Ubangi over the 210/211. Unfortunately, quality costs, so neither had much market penetration and their construction are beyond the skills/tools of the casual DIYer.
As far as port tuning goes, the response norm for PA systems hasn't changed since the late '30s: F24 = ~40 Hz, F6/Fb = ~60 Hz, F0 = ~80 Hz and nominally flat out to ~300 Hz and why the A2, etc., had a 40-50 Hz Fs woofer and the A800 had a ~50 - 60 Hz Fs woofer until the 'bean counters' started consolidating driver variations when driver Fs was lowered to keep pace with changes in amp design, especially WRT increased damping [DF].
This of course doesn't account for the huge vent area [Av]; it's due to the fact that the rear cab isn't a simple reflex, i.e. a true Helmholtz resonator where the optimum/max size is Av = driver
Bear and I will have to agree to disagree about how knowledgeable the pioneers were since like virtually every horn/cab design these professional electrical, mechanical, acoustical engineers created, these two mass loaded [vented] compound horn designs are proof that they 'had a clue' several decades before T/S filter theory became popular.
As best I can tell, all T/S filter theory really did was bring the pioneer's speaker system design knowledge 'buried' in patents, AES, etc., papers and college level physics, etc., textbooks to the masses [AKA 'the great unwashed' of which I'm a many decades long card carrying member
].GM
You're welcome and glad to be of help. It's one of my favorite subjects.
I used the DEQ2496 for active EQ and it was just fine, since most of my music is in digital format. I did run the turntable thru a phono preamp and then into an ADC at 48K/24 and on to the DEQ. Probably not the purest way to do it, but my record collection is almost entirely $1 finds and estate sale bargains.
The appeal of a simple signal path is not lost on me, for sure. If you can do it, so much the better!
Surprisingly, no. In the bass I used active EQ simply to tame a peak circa 225 Hz that might have been the room, or the speakers, or both.They were too heavy to drag outside for testing, so I don't know. No bass boost. Tried it, didn't like it - and it was not needed with corner placement. When I did a lot of live sound mixing, 125 Hz was something you could always cut to clean up the system. 250 Hz would sometimes need to be cut, too. Pretty common in the P.A. live sound biz.
I used the DEQ2496 for active EQ and it was just fine, since most of my music is in digital format. I did run the turntable thru a phono preamp and then into an ADC at 48K/24 and on to the DEQ. Probably not the purest way to do it, but my record collection is almost entirely $1 finds and estate sale bargains.
The appeal of a simple signal path is not lost on me, for sure. If you can do it, so much the better!
Greets!
You're welcome!
Actually, if you go back and use the 'added series resistance calculator' I posted the other day, you'll find it has a huge impact on the driver's damping [Qts] in that it reduces the driver/cab system Q [sysQ], increasing the perceived [mid] bass, so factoring in it's a zero nfb tube amp, then until you tune them to each driver's actual Fs [low 20s normally for a 416A] you won't know if a much lower than stock tuning is the way to go.
Note you may still need some extra added series resistance to tonally balance it out over a very wide BW since these cab alignments were voiced with a matching impedance as you can see from this early measurement with an 803: http://www.classicspeakerpages.net/...urve.jpg.24a1baf1147e1542f756b1ee9d1d3ac7.jpg
GM
Hi GM,
Very interesting, and thank you once again. The last thing I ever considered was to add a small value series resistance between the output of my amplifiers and the woofer to obtain an optimum impedance match between the two, for enhanced or optimum bass performance!
I can certainly plug in the variables to the "added series resistance calculator" you had provided to me a few days ago, and see what the optimum result may be.
Many years ago, I was very friendly with an old-time audio engineer, who has since passed on. He told me that Altec had deliberately designed the damping factor/output impedance of their own vacuum tube amplifiers to provide the ideal match to their loudspeaker systems, insofar as optimum bass performance was concerned. Based upon his extensive knowledge, I believed then as I do now that this was a credible statement. He further mentioned that this was one reason why the bass performance of the high efficiency Altec speaker systems suffered when these speakers were used with modern solid-state amplifiers having a high DF, with the bass becoming very lean or thin as a result, due to overcontrol of the bass driver by the amplifier. This appears to be in line with your comments.
I have seen that frequency response curve many times for the A-7 system, and I always thought the measured response around the region of 60 to 35 Hz was somewhat optimistic. I wonder if this plot was for the earlier 803 bass driver, where Fs was (I think) 50 Hz, or the later version of the 803 where Fs was reduced to 25 Hz. I further believe that when Altec introduced the 25 Hz Fs version of the 803, was when they substantially reduced the two reflex port area of the original late 1940s 825 cabinet, to the single 210 square inch reflex port, to take advantage of the 25 Hz Fs driver.
Thanks & Best Regards,
Bruce
Very interesting, and thank you once again. The last thing I ever considered was to add a small value series resistance between the output of my amplifiers and the woofer to obtain an optimum impedance match between the two, for enhanced or optimum bass performance!
I can certainly plug in the variables to the "added series resistance calculator" you had provided to me a few days ago, and see what the optimum result may be.
Many years ago, I was very friendly with an old-time audio engineer, who has since passed on. He told me that Altec had deliberately designed the damping factor/output impedance of their own vacuum tube amplifiers to provide the ideal match to their loudspeaker systems, insofar as optimum bass performance was concerned. Based upon his extensive knowledge, I believed then as I do now that this was a credible statement. He further mentioned that this was one reason why the bass performance of the high efficiency Altec speaker systems suffered when these speakers were used with modern solid-state amplifiers having a high DF, with the bass becoming very lean or thin as a result, due to overcontrol of the bass driver by the amplifier. This appears to be in line with your comments.
I have seen that frequency response curve many times for the A-7 system, and I always thought the measured response around the region of 60 to 35 Hz was somewhat optimistic. I wonder if this plot was for the earlier 803 bass driver, where Fs was (I think) 50 Hz, or the later version of the 803 where Fs was reduced to 25 Hz. I further believe that when Altec introduced the 25 Hz Fs version of the 803, was when they substantially reduced the two reflex port area of the original late 1940s 825 cabinet, to the single 210 square inch reflex port, to take advantage of the 25 Hz Fs driver.
Thanks & Best Regards,
Bruce
You're welcome and glad to be of help. It's one of my favorite subjects.
Surprisingly, no. In the bass I used active EQ simply to tame a peak circa 225 Hz that might have been the room, or the speakers, or both.They were too heavy to drag outside for testing, so I don't know. No bass boost. Tried it, didn't like it - and it was not needed with corner placement. When I did a lot of live sound mixing, 125 Hz was something you could always cut to clean up the system. 250 Hz would sometimes need to be cut, too. Pretty common in the P.A. live sound biz.
I used the DEQ2496 for active EQ and it was just fine, since most of my music is in digital format. I did run the turntable thru a phono preamp and then into an ADC at 48K/24 and on to the DEQ. Probably not the purest way to do it, but my record collection is almost entirely $1 finds and estate sale bargains.
The appeal of a simple signal path is not lost on me, for sure. If you can do it, so much the better!
Thanks very much, Pano.
Would you perhaps have the frequency response plot of your A-5 below the cut-off of the short horn? That would be interesting to see, even if the response may have been somewhat enhanced by corner placement of the system, etc. It would be great to see the frequency response before your modifications to the enclosure, and after, assuming of course that you recorded the data when you were hard at work on improving the bass performance of the speaker.
Best Regards,
Bruce
Greets!
AFAIK, there's no surviving pioneering Altec engineers, only some who came to work long after these systems were designed [circa 1941 for the 'A' series and circa 1947 for the A800] and none AFAIK post on any forums or otherwise available to the general public to 'pick their brains'.
That said, there's plenty of folks that knows at least some of the history and fully understand the 'physics of the situation', so these designs hold no secrets AFAIK as their 'bones' were picked clean as soon as they became available by RCA's Harry Olson and then improved upon. You want a superior performing A5/A7? Restore/replicate his LC-9A with original, or better still, modern drivers. Ditto his Ubangi over the 210/211. Unfortunately, quality costs, so neither had much market penetration and their construction are beyond the skills/tools of the casual DIYer.
As far as port tuning goes, the response norm for PA systems hasn't changed since the late '30s: F24 = ~40 Hz, F6/Fb = ~60 Hz, F0 = ~80 Hz and nominally flat out to ~300 Hz and why the A2, etc., had a 40-50 Hz Fs woofer and the A800 had a ~50 - 60 Hz Fs woofer until the 'bean counters' started consolidating driver variations when driver Fs was lowered to keep pace with changes in amp design, especially WRT increased damping [DF].
This of course doesn't account for the huge vent area [Av]; it's due to the fact that the rear cab isn't a simple reflex, i.e. a true Helmholtz resonator where the optimum/max size is Av = drivereffective piston area [Sd], but a crude, high tuned BLH, which is acoustically amplifying the driver's ability to load said vent, hence the need for a ~2x Sd/Av for a given tuning.
Bear and I will have to agree to disagree about how knowledgeable the pioneers were since like virtually every horn/cab design these professional electrical, mechanical, acoustical engineers created, these two mass loaded [vented] compound horn designs are proof that they 'had a clue' several decades before T/S filter theory became popular.
As best I can tell, all T/S filter theory really did was bring the pioneer's speaker system design knowledge 'buried' in patents, AES, etc., papers and college level physics, etc., textbooks to the masses [AKA 'the great unwashed' of which I'm a many decades long card carrying member
GM
Thanks as always, GM! Your, Pano's, and Bears's knowledge on these issues is most impressive. As I had mentioned previously, I am an electronics guy, and not so much a speaker guy, and I have learned much about the subject from all of you. It is now very apparent to me that I have to become much more conversant with loudspeaker design and theory.
It is too bad that John Hilliard is no longer with us, as he would be a wealth of information on all of the technical issues and design criteria related to the original Voice of the Theatre product line. But as you also indicated, the theory and design for these systems are not new technology, and can be clearly analyzed by folks knowledgeable with loudspeaker technology. The physics relating to these systems will never change.
Best Regards,
Bruce
Maybe. I took 100s of measurements, but my ability to give them accurate and useful labels is sorely lacking.
I probably have the measurements, but can't be sure I've named them correctly. I'll dig thru in hopes of finding something.Hello Pano & GM!
It's been awhile, but I figured that I would let you guys know that after a lot of serious listening, I did decide to reduce the port area of my A-5 bass enclosures to approximately 80 square inches.
This definitely tightens up and extends the low bass response of the system, and I really like the result. I'm leaving the bass reflex port area at 80 square inches, and I'm very happy with the sound of the system at this point.
I did try using a REL subwoofer with the A-5s, but this was a big mistake. The subwoofer can't keep up with bass driver speed in the A-5 enclosure, and the bass sounded unnatural and poorly balanced. Although you lose the lowest octave of bass performance by removing the subwoofer, the result is that the A-5s are extremely pleasant to listen to as-is.
It's been awhile, but I figured that I would let you guys know that after a lot of serious listening, I did decide to reduce the port area of my A-5 bass enclosures to approximately 80 square inches.
This definitely tightens up and extends the low bass response of the system, and I really like the result. I'm leaving the bass reflex port area at 80 square inches, and I'm very happy with the sound of the system at this point.
I did try using a REL subwoofer with the A-5s, but this was a big mistake. The subwoofer can't keep up with bass driver speed in the A-5 enclosure, and the bass sounded unnatural and poorly balanced. Although you lose the lowest octave of bass performance by removing the subwoofer, the result is that the A-5s are extremely pleasant to listen to as-is.
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Greets!
An optimally placed REL can keep up with a 515GHP compression FLH, though takes duals to keep up at higher SPL, so an A5 poses no problems, but regardless of driver, etc.; blending a sub to a reflex requires the reflex to be sealed or at least tuned an octave or more below the XO point.
GM
An optimally placed REL can keep up with a 515GHP compression FLH, though takes duals to keep up at higher SPL, so an A5 poses no problems, but regardless of driver, etc.; blending a sub to a reflex requires the reflex to be sealed or at least tuned an octave or more below the XO point.
GM
Agree with GM - blending a sub won't be easy.
Perhaps it's the type of music I listen to, but getting down to the mid 30s or even lower 40s - with authority - is plenty for me. The A5 just sounds like real people playing real instruments in a real space. And that's what I want from a speaker.
Perhaps it's the type of music I listen to, but getting down to the mid 30s or even lower 40s - with authority - is plenty for me. The A5 just sounds like real people playing real instruments in a real space. And that's what I want from a speaker.
About integrating a subwoofer: I built a sub slot loading 4 RCF 15" drivers. The slot has 50cm wings on the sides and top and is moved into a corner with the ends of the wings touching the walls. What helps immensely in my case is using a Crown XTi 1200. It doesn't sound that great when used full range but below 100Hz it's good enough and the integrated DSP helps a lot.