I'm using a Dallas 2 as my main speaker (fe206e 8" full range). I'm quite happy with the bass, but I can't help but wonder if I should supplement it with a subwoofer and use a high-pass filter on the Dallas?
My theory is that when the Dallas is dealing with a 30hz signal, it must be difficult to keep enough driver control to also produce a clean 500hz concurrently. If I put a high pass filter on so the fostex doesn't have to stress itself with heavy bass, it should be cleaner in the "music" range.
That's my theory at least. Really, I know nothing about speaker design.
Opinions and advice please.
My theory is that when the Dallas is dealing with a 30hz signal, it must be difficult to keep enough driver control to also produce a clean 500hz concurrently. If I put a high pass filter on so the fostex doesn't have to stress itself with heavy bass, it should be cleaner in the "music" range.
That's my theory at least. Really, I know nothing about speaker design.
Opinions and advice please.
I'd argue that the phase curve produced by a crossover is by far a lesser evil than the distortion caused by the driver's voicecoil exiting the gap. That's not to mention the fact that the cabinet's LF rolloff already has it's own phase wiggles.
Just adding a sub will usually increase low-frequency level and/or extension. If you put a highpass filter on the midrange driver, you lower the distortion it's producing. Combine the two for the best effect.
The next step in that direction is to use a smaller full-range unit (generally better HF performance) in a small sealed compartment, and cross at 2-400Hz to a 6-8" midbass driver. Having the crossover higher up means even the small drivers can run comfortably at loud levels - 100Hz still requires a bit of cone movement.
Chris
I believe that in most blh designs, the horn is only active from about 300hz and below. What are you listening to and at what level? If I were to use a sub I'd cross it over fairly low like about 50hz so my dallas still handles most of the bass since you're "quite happy" with it. Then it becomes a question of how much money do you want to invest for that small benefit?
It probably never hurts to BOTH relieve a smaller (less than 8"?) FR driver from the heavy lifting with HP filtering below, say, at least 80-100Hz, and reinforce with (sub)woofers - separately powered is my preference. Once you go high enough, stereo woofers should be considered essential. Call it what you like, it's a two-way system, just crossed over lower than the more commonly seen values anywhere between 1000-3200Hz.
Of several such combinations I've built over the past few years, my most satisfying results were with a 4" FR and pair of 6" mid bass per side. As neither of my listening spaces are friendly to BLH large enough to operate - aided or not- to the lowest couple of octaves, these enclosures were a floorstanding MTM. They're not narrow, but shallow enough to not encroach on floorspace, and being monopoles, placement with regards to side and rear walls and furniture is not as critical.
I always like a design that works for the room as it is, not shoehorn something that sounds great in a large, open space into a room constrained by size, shape and furniture . Not everyone has such restrictions, but until I have an ideal situation, WAF rules.
Of several such combinations I've built over the past few years, my most satisfying results were with a 4" FR and pair of 6" mid bass per side. As neither of my listening spaces are friendly to BLH large enough to operate - aided or not- to the lowest couple of octaves, these enclosures were a floorstanding MTM. They're not narrow, but shallow enough to not encroach on floorspace, and being monopoles, placement with regards to side and rear walls and furniture is not as critical.
I always like a design that works for the room as it is, not shoehorn something that sounds great in a large, open space into a room constrained by size, shape and furniture . Not everyone has such restrictions, but until I have an ideal situation, WAF rules.
Well, what is important for you? Do you appreciate the deep pinpoint precise sound stage a pair of Dallas II is presenting or do you need even more bass than it already has? You can't have both unfortunately, because physics...
I found the bass on mine to be very fast, tight and impact full, but it won't be a stomach shaker, that's for sure. For me it is more than enough (live jazz, rock&roll, classic), at speaking voice volumes (OK, occasionally also louder).
If you love thumping 20Hz music (trance, house, electronica, etc), at high volumes, then you're probably better served with another design altogether.
>My theory is that when the Dallas is dealing with a 30hz signal, it must be difficult to keep enough driver control to also produce a clean 500hz concurrently.
That only at very high listening volumes, where the combined excursion caused by adding the two signals is more than the maximal one. The driver then behaves as a compressor. Driver control is a question of the amplifier, and if you have doubts, you can try them with a different 30 W amp, and see if it sounds better.
I found the bass on mine to be very fast, tight and impact full, but it won't be a stomach shaker, that's for sure. For me it is more than enough (live jazz, rock&roll, classic), at speaking voice volumes (OK, occasionally also louder).
If you love thumping 20Hz music (trance, house, electronica, etc), at high volumes, then you're probably better served with another design altogether.
>My theory is that when the Dallas is dealing with a 30hz signal, it must be difficult to keep enough driver control to also produce a clean 500hz concurrently.
That only at very high listening volumes, where the combined excursion caused by adding the two signals is more than the maximal one. The driver then behaves as a compressor. Driver control is a question of the amplifier, and if you have doubts, you can try them with a different 30 W amp, and see if it sounds better.
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In response to the 2 specific questions about what I listen to- Various styles of music, including hiphop and rock. Often loud. I'll often see my drivers pumping to a drum beat and think "this can't be good for the drivers, or the sound".
As for what is important to me? Only nice "fidelity" really (as in- the accurate reproduction of sound). I'm not aiming for booming bass or anything. I'm just thinking of taking away extra stresses on the Dallas so that it can focus on fidelity without being overcome by trying to produce bass at the same time.
The reason I like the fullrange driver is really just because it seems "natural" to me. A trumpet lets out one note at a time- not three notes (thus, 3 drivers seems unrealistic). Likewise, to my best knowledge things are recorded using fullrange mics rather than 3-way mics.
Of course my impression of fullrange vs multi-way isn't exactly an accurate representation of speaker technology, but it's a feeling I get when I listen to fullrange. Obviously using a subwoofer goes against that a bit, but.....
As for what is important to me? Only nice "fidelity" really (as in- the accurate reproduction of sound). I'm not aiming for booming bass or anything. I'm just thinking of taking away extra stresses on the Dallas so that it can focus on fidelity without being overcome by trying to produce bass at the same time.
The reason I like the fullrange driver is really just because it seems "natural" to me. A trumpet lets out one note at a time- not three notes (thus, 3 drivers seems unrealistic). Likewise, to my best knowledge things are recorded using fullrange mics rather than 3-way mics.
Of course my impression of fullrange vs multi-way isn't exactly an accurate representation of speaker technology, but it's a feeling I get when I listen to fullrange. Obviously using a subwoofer goes against that a bit, but.....
Hmm, based on this, you'll need a seriously powerful ~40-150 Hz woofer/mid-bass system emphasis relative to the mains for hip-hop, with output to ~20 Hz to cover some other bass heavy music: http://thehub.musiciansfriend.com/tech-tips/eq-curves-and-musical-style
GM
GM
Relieving fullrange from low frequencies, say below 100 Hz, is always beneficial, resulting in lower distortion, cleaner sound.
There are many ways to do it. One option is to get an active sub, or two, with its own amp and adjustable level and crossover, and high passing the signal to fullrange with caps.
Second option would be simple active crossover, and biamp the system. There are many other variants of these options, like mini dsp, which can not only split the signal, but do lot more to eq each section to measure flat in listening position, that is to correct some room anomalies as well...
There are many ways to do it, each has its pros and cons, but they all can lead to significant improvement, depending on execution.
There are many ways to do it. One option is to get an active sub, or two, with its own amp and adjustable level and crossover, and high passing the signal to fullrange with caps.
Second option would be simple active crossover, and biamp the system. There are many other variants of these options, like mini dsp, which can not only split the signal, but do lot more to eq each section to measure flat in listening position, that is to correct some room anomalies as well...
There are many ways to do it, each has its pros and cons, but they all can lead to significant improvement, depending on execution.
hugz Dallas
Hello, my opinion,
1, Dallas ist like it is, may be first change the driver to the SICA 38/1100 8"
2, add a sub only aktive, 18 dB
3, reduce bass in dallas only active, make a IMP measurement, passive not easy.
4, if you reduce the bass in the dallas, (a shame imho) you have a large enclosure
you don´t need.
my solution would be SCHALMEI SAT with ALPHORN or RDH20
Hello, my opinion,
1, Dallas ist like it is, may be first change the driver to the SICA 38/1100 8"
2, add a sub only aktive, 18 dB
3, reduce bass in dallas only active, make a IMP measurement, passive not easy.
4, if you reduce the bass in the dallas, (a shame imho) you have a large enclosure
you don´t need.
my solution would be SCHALMEI SAT with ALPHORN or RDH20
Attachments
Dallas II was designed for the FE206E, using advanced simulation software and know-how. Both the horn and the baffle area are optimized for it. Changing the driver to something else (especially not coming from Fostex) will most certainly make it sound worse. There are threads of people playing around with other drivers and returning to the 206E
in Dallas II.
> if you reduce the bass in the dallas, (a shame imho) you have a large enclosure you don´t need.
Exactly - The driver and the enclosure are that big just for allowing the bass to go as low as 40-50 Hz, and still be extremely fast. It's a shame to modify it. People are USED to music being bass heavy, but if you listen to the Dallas II with a high quality source (I used an Audion Edison 60 kit tube amp and a very good DAC, and mostly FLAC files) for a while and get used to its qualities, you will have problems going to other speakers afterwards.
in Dallas II.> if you reduce the bass in the dallas, (a shame imho) you have a large enclosure you don´t need.
Exactly
- The driver and the enclosure are that big just for allowing the bass to go as low as 40-50 Hz, and still be extremely fast. It's a shame to modify it. People are USED to music being bass heavy, but if you listen to the Dallas II with a high quality source (I used an Audion Edison 60 kit tube amp and a very good DAC, and mostly FLAC files) for a while and get used to its qualities, you will have problems going to other speakers afterwards.
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So here is my take on it fb2017...not a criticism, just my opinion.
While achieving 40-50 Hz may be enough for some, I do like to hear clear down to 30Hz, maybe even lower. My main system has 2x 15" per side, with eq, I get very solid clean 30Hz, even 20Hz is achievable, but I do not want to rattle the apartment too much.
When you look at line of speakers from well established manufactures, you see from small bookshelf to their top of the line model, main feature which mostly improve is extension into low frequencies. Often even tweeters and mids may be the same. Maybe not, maybe top of the line model has better mid, fancier tweeter, with more power handling, but performance wise, not too different.
Its the execution at lowest frequencies, which will make it ultimately HiFi or HiEnd. If its missing lowest octave, it will never sound like real thing.
Many will disagree here with me, mostly from fullrange camp, accustomed to listen to puny drivers with no low end, and that is perfectly fine with me. (I call it bonsai sound, it may be nice, cute, but its no forest). I spent many years with Lowthers and BLHs, and one day I finally got rid of them and never looked back.
Here is one observation I noticed over the years. Using small bookshelf speakers, or rather compromised fullrange speakers with poor low fr response, people naturally will use loudness pot, or +bass pot on their preamp or integrated amp, and when you plot the resulting frequency curve, you end up with ugly bump in midbass. While you may lift some missing low frequencies, due to the shape of +/- bass/treble curves, which typically shoot up from 1kHz, you end up with ugly midbass muddy sounding system.
Parametric equalizer with selectable turn around frequency, or 15 or even better 31 band equalizer is only acceptable.
If the speaker rolls of below 40Hz, loudness pot, +bass pot only makes things worse.
I use Behringer 31 digital eq.
So back to the issue, main speakers are big, so? If that is not a problem for the owner, I would still recommend to add as subwoofer (or two) and gently limit bass to BLHs.
While achieving 40-50 Hz may be enough for some, I do like to hear clear down to 30Hz, maybe even lower. My main system has 2x 15" per side, with eq, I get very solid clean 30Hz, even 20Hz is achievable, but I do not want to rattle the apartment too much.
When you look at line of speakers from well established manufactures, you see from small bookshelf to their top of the line model, main feature which mostly improve is extension into low frequencies. Often even tweeters and mids may be the same. Maybe not, maybe top of the line model has better mid, fancier tweeter, with more power handling, but performance wise, not too different.
Its the execution at lowest frequencies, which will make it ultimately HiFi or HiEnd. If its missing lowest octave, it will never sound like real thing.
Many will disagree here with me, mostly from fullrange camp, accustomed to listen to puny drivers with no low end, and that is perfectly fine with me. (I call it bonsai sound, it may be nice, cute, but its no forest). I spent many years with Lowthers and BLHs, and one day I finally got rid of them and never looked back.
Here is one observation I noticed over the years. Using small bookshelf speakers, or rather compromised fullrange speakers with poor low fr response, people naturally will use loudness pot, or +bass pot on their preamp or integrated amp, and when you plot the resulting frequency curve, you end up with ugly bump in midbass. While you may lift some missing low frequencies, due to the shape of +/- bass/treble curves, which typically shoot up from 1kHz, you end up with ugly midbass muddy sounding system.
Parametric equalizer with selectable turn around frequency, or 15 or even better 31 band equalizer is only acceptable.
If the speaker rolls of below 40Hz, loudness pot, +bass pot only makes things worse.
I use Behringer 31 digital eq.
So back to the issue, main speakers are big, so? If that is not a problem for the owner, I would still recommend to add as subwoofer (or two) and gently limit bass to BLHs.
Yes, but that's always your solution, along with the paid plans on your website.
+1 on what Adason said. 20Hz is easily attainable these days, but that rarely involves a horn. Usually a sealed box with one or more 12-18" drivers and a couple of kilowatts.
With some room gain, I measured one of my 15" subs as being pretty flat down to 12Hz. Again, this is not the realm of full-range drivers and BLHs. They do their own thing. Extreme bass extension is not one of them.
Chris
I've made the opposite step, going from a good 7.1 600W system to a stereo tube amp powered fullrange one (still have and used them both actually). Each has advantages and disadvantages. I'm not sure what drivers you're referring to, but I'm sure very very few people would call the Dallas II sound bonsai or puny, or its bass lacking.
And for their needs, other, more adequate systems can be built (including adding subs to the DII) for a bit more money, no question about that.
Carfrae Little Big Horn
The Carfrae Little Big Horn 6moons audio reviews: RoadTour Exit 1 with Michael Lavorgna which was a commercial offering, is an example of fullrange sub integration that works very well.
SMathews
The Carfrae Little Big Horn 6moons audio reviews: RoadTour Exit 1 with Michael Lavorgna which was a commercial offering, is an example of fullrange sub integration that works very well.
SMathews
Yeah, unfortunately I don't really think that people using porcelain insulators for the cables, and say that "black CDs sound better" have any idea about how to design speakers either. They totally lost me here: "[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]But that's not the end of this tweak. As the story goes, in order to get the best transfer to a black disk, you need a dedicated laptop with an external CD burner. And during the burning process, the laptop runs off its battery. "
Geez -
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Geez -
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