Dave,
Sorry I should have said 'Jaguar" thats the one recommended for the 10 driver in that range of designs by Scott.
I like the fact that that all comes through the front also a neater footprint in comparison to the Silbury. My thinking is that the "Jaguar" just may work better in the room as moving them forward will not be an option,,, but I could be wrong in that assumption and the Silbury may work better,, don't know. There really is going to be a huge amount of fabric behind each speaker. Conversely I enjoy the idea of the Silburys commanding 6 ft of height. It would also leave the driver sitting at what I feel to be a nice height of 3ft.
The pencil would be an easy option if a bit utilitarian in the looks department,
I suppose if anything I am drawn to the Silbury at present, have you heard a pair or have you any impressions or thoughts,, has anyone around here even built a pair?
Ray
Sorry I should have said 'Jaguar" thats the one recommended for the 10 driver in that range of designs by Scott.
I like the fact that that all comes through the front also a neater footprint in comparison to the Silbury. My thinking is that the "Jaguar" just may work better in the room as moving them forward will not be an option,,, but I could be wrong in that assumption and the Silbury may work better,, don't know. There really is going to be a huge amount of fabric behind each speaker. Conversely I enjoy the idea of the Silburys commanding 6 ft of height. It would also leave the driver sitting at what I feel to be a nice height of 3ft.
The pencil would be an easy option if a bit utilitarian in the looks department,
I suppose if anything I am drawn to the Silbury at present, have you heard a pair or have you any impressions or thoughts,, has anyone around here even built a pair?
Ray
The WAW approach doesn't require active crossovers. It totally depends on use case, the drivers selected, and the skill of the crossover/cabinet designer. Dave and I are discussing a WAW option for my system with all Alpair drivers. I have no idea whether they are actively or passively integrated, or if they require more than one amp.
It sounds like you've got quite a collection of drivers. I'm certain the gents here can help you build something fantastic.
Yes I have quite a collection of drivers,, If time could talk it would have tales to tell of my escapades over the years with speakers,,, and audio in general.
Sound and electronics amazed me even as a child,, I was ten when I bought my first soldering iron and had to hide it from my mother.
As I would see it regarding an active x-over,,, if you remove the lower frequencies from the main driver you are at least reducing the excursion of the driver which may clean things up or at least be kinder on the driver. You are then just left with marrying the two sounds to get as cohesive a sound as possible. I know it can be achieved without a crossover and a sub which would simplify things. The guy that built my amp uses a pair of the first quad electrostatics and a Monolith type sub he built, just to reinforce the lower end,, anyone who hears it is impressed,, but again his amplification is tops!
The one thing I can say for certainty is that I would never be tempted to go back to multi-driver speakers,, I know that as I have plenty and I just don't use them even if I can't bare to part with them. Yes it's an illness!
Ray
You would need a crossover of some kind for sure to high-pass the wideband driver. A line-level passive x-over has been recommended by Dave, but I don't know anything about them yet. If not that, then I guess active is the way to go.
My problem with active crossovers/DSP is that I have a very nice DAC and I don't want to take the signal from that and feed it back into a digital active crossover. Kinda defeats the purpose of a nice DAC. There might be an good solution out there, but I don't know what it is. I haven't looked into MiniDSP as yet.
My problem with active crossovers/DSP is that I have a very nice DAC and I don't want to take the signal from that and feed it back into a digital active crossover. Kinda defeats the purpose of a nice DAC. There might be an good solution out there, but I don't know what it is. I haven't looked into MiniDSP as yet.
You're right, of course. I'm listening to mine right now and there is no crossover on my wideband. Just a woofer/subwoofer (not sure which I should call it) crossed in at around 140hz with a separate amp to fill in the bottom octaves.
That said, I very much want to add a high-pass filter. The sound gets quite muddled at anything more than medium volume due, I assume, to the excursion required to reproduce low frequencies.
That said, I very much want to add a high-pass filter. The sound gets quite muddled at anything more than medium volume due, I assume, to the excursion required to reproduce low frequencies.
Use an analogue active crossover after your DAC. Info here on passive line level TLS.org | Passive Line-Level Crossover
Wow. Thanks, Scott.
Since these are before the amp, do they affect phase?
I had better look up the output impedance of my preamp and the input impedance of my power amps.
Do you just mount these on a board or in a box with RCA connections? Seems easy enough.
A lot of comments to address.
1/ woofer vrs midWoofer. A woofer will likely go lower but for good integration, even with a subwoofer, you want a fairly extended top end on the bass helper. For example, in our successful WAW experiments woofers have response to 1.7k (SDX7eN), 5k (SF W14), 10k (Peerless 830870), 10k (Alpair 12pw). I expect the special 10” i have for 1 more OB attempt go to at least 1k, and the vintage 12” for another were XOed at 3.5k to a tweeter.
One has to be careful to avoid woofers that are better described as atmosphere generators.
2/ there are 2 ways to approach this.
The 1st is what i call the “Rel” method as it is advocated by them. This is to only have a low pass on the woofer and fill in below the natural LF performance of the full-range. It is hard to get a FR to naturally roll-off much above 150 Hz unless it is really small. This approach means nothing impinges on the FR performance, but it also limits you to the envelope of the FRs performance. I call this approach, adding a subwoofer (even if it is a woofer). If one is planning this from the start then the enclosure of choice is often sealed (Target Q=0.707) which gives a fairly well defined 2nd order roll-off at 1 specific frequency.
The 2nd approach is to put an XO on both sides and move the XO point upwards. Here the FR is impacted by the XO, but it is usually at such a low frequency that the ear/brain has trouble detecting the problems associated with the XO roll-off. It does not mean that issues with electronics (digital or analog) adding some electronic haze to everything. This, and cost, are one of the reasons i like PLLXOs if possible, at least of the Hi-Pass side. One would think that the biggest benefit is the addition of more impactful and more extended bass, but in practise the improvement mid and top because the FR no longer has to do heavy lifting is the biggest gain. This method also allows for greater potential levels, and allows the HF amplifier to also perform better by excluding the need to produce LF. This of particular benefit to small amplifiers, the usual suspects SE tube amps, amps by Firstwatt or inspired by them, and other small Class A amps. Amps can even be specifically designed for HF use only with an unusually high bass corner (a particular benefit if designed an output transformer).
3/ PLLXOs are very limited, but also very simple, transparent (no electronics haze), and cheap. One can do a 2nd order XO but with no feedback it is quite droopy. One alos has to have a lot of pre-amp grunt (and low output impedance), and an amp with a high input impedance to even be able to do a 2nd order version. A PLLXO really shines when it is 1st order. This brings all the benefits and shortcomings of a 1st order filter. First one needs to have extended bandwidth well beyond the XO frequency to get textbook results, in practise the midTweeter will often start rolling off faster since it is rolling off faster before 2-3 octaves below the XO. This is not as bad as one may think as the room is typically dominating in this region and one has far worse issues. Benefits have already been mentioned in the 1st sentence. The LP for each channel is a series resistor and a small cap in shunt to the amp input. The HP can be just a small cap in series with the input of the amp. Each HP filter is very specific to the amp used as the R part of the filter is the amp’s input resistance. One usually does need to have a gain control on one of the amplifiers, in practise the LF amp is more likely but that is dependent on the amplifier gains. Phase performance of the filter is very good as one expects from a first-order XO working into a well defined load, and if one can get the driver centre-to-centres within a ¼ wavelength at the XO frequency the drivers become essentially coincident and the typical worries about driver centres and lobing go away… like a co-axial but without the inherent issues of the high XO frequency usually seen in those. So one can get very good phase performance, even thou doen this low issues with phase coherence and linearity become had to distinguish.
If one wants to get as close to a PLLXO as possibly but with greater versatily then i’d suggest that the XOs that are essentially PLLXO stages sandwiched between something like PASS B1 FET buffer stages is the way to go. I believe that the Firstwatt B4 & B5 are implemented this way.
4/ passive XOs. These are very tricky to implement as the impedance of what we are trying to XO is all over the map and the parts needed are very large. In all the WAWs were we have done an effective passive XO the XO frequency has ended up being higher then what it was when we used a PLLXO, and the size & cost of passive parts could easily be in excess of what it would cost for a PLLXO & one of the new Class D bass amps.
Sorry for the length of the post, but there was a lot to cover. Questions?
dave
1/ woofer vrs midWoofer. A woofer will likely go lower but for good integration, even with a subwoofer, you want a fairly extended top end on the bass helper. For example, in our successful WAW experiments woofers have response to 1.7k (SDX7eN), 5k (SF W14), 10k (Peerless 830870), 10k (Alpair 12pw). I expect the special 10” i have for 1 more OB attempt go to at least 1k, and the vintage 12” for another were XOed at 3.5k to a tweeter.
One has to be careful to avoid woofers that are better described as atmosphere generators.
2/ there are 2 ways to approach this.
The 1st is what i call the “Rel” method as it is advocated by them. This is to only have a low pass on the woofer and fill in below the natural LF performance of the full-range. It is hard to get a FR to naturally roll-off much above 150 Hz unless it is really small. This approach means nothing impinges on the FR performance, but it also limits you to the envelope of the FRs performance. I call this approach, adding a subwoofer (even if it is a woofer). If one is planning this from the start then the enclosure of choice is often sealed (Target Q=0.707) which gives a fairly well defined 2nd order roll-off at 1 specific frequency.
The 2nd approach is to put an XO on both sides and move the XO point upwards. Here the FR is impacted by the XO, but it is usually at such a low frequency that the ear/brain has trouble detecting the problems associated with the XO roll-off. It does not mean that issues with electronics (digital or analog) adding some electronic haze to everything. This, and cost, are one of the reasons i like PLLXOs if possible, at least of the Hi-Pass side. One would think that the biggest benefit is the addition of more impactful and more extended bass, but in practise the improvement mid and top because the FR no longer has to do heavy lifting is the biggest gain. This method also allows for greater potential levels, and allows the HF amplifier to also perform better by excluding the need to produce LF. This of particular benefit to small amplifiers, the usual suspects SE tube amps, amps by Firstwatt or inspired by them, and other small Class A amps. Amps can even be specifically designed for HF use only with an unusually high bass corner (a particular benefit if designed an output transformer).
3/ PLLXOs are very limited, but also very simple, transparent (no electronics haze), and cheap. One can do a 2nd order XO but with no feedback it is quite droopy. One alos has to have a lot of pre-amp grunt (and low output impedance), and an amp with a high input impedance to even be able to do a 2nd order version. A PLLXO really shines when it is 1st order. This brings all the benefits and shortcomings of a 1st order filter. First one needs to have extended bandwidth well beyond the XO frequency to get textbook results, in practise the midTweeter will often start rolling off faster since it is rolling off faster before 2-3 octaves below the XO. This is not as bad as one may think as the room is typically dominating in this region and one has far worse issues. Benefits have already been mentioned in the 1st sentence. The LP for each channel is a series resistor and a small cap in shunt to the amp input. The HP can be just a small cap in series with the input of the amp. Each HP filter is very specific to the amp used as the R part of the filter is the amp’s input resistance. One usually does need to have a gain control on one of the amplifiers, in practise the LF amp is more likely but that is dependent on the amplifier gains. Phase performance of the filter is very good as one expects from a first-order XO working into a well defined load, and if one can get the driver centre-to-centres within a ¼ wavelength at the XO frequency the drivers become essentially coincident and the typical worries about driver centres and lobing go away… like a co-axial but without the inherent issues of the high XO frequency usually seen in those. So one can get very good phase performance, even thou doen this low issues with phase coherence and linearity become had to distinguish.
If one wants to get as close to a PLLXO as possibly but with greater versatily then i’d suggest that the XOs that are essentially PLLXO stages sandwiched between something like PASS B1 FET buffer stages is the way to go. I believe that the Firstwatt B4 & B5 are implemented this way.
4/ passive XOs. These are very tricky to implement as the impedance of what we are trying to XO is all over the map and the parts needed are very large. In all the WAWs were we have done an effective passive XO the XO frequency has ended up being higher then what it was when we used a PLLXO, and the size & cost of passive parts could easily be in excess of what it would cost for a PLLXO & one of the new Class D bass amps.
Sorry for the length of the post, but there was a lot to cover. Questions?
dave
FWIW, I've found that when using "FR / wide-band" drivers such as most of the Fostex and Mark Audio / Alpairs with which I've been playing for the past 10yrs or so, the simpler "REL" technique definitely has drawbacks in terms of limiting the increase in SPLs and dynamics that one would be expecting the addition of (sub)-woofers to add.
The natural tendency would be to turn up the wick a little bit more, and the FR drivers can easily be driven past their comfortable operating area. The bass management - and in some cases bi-amping capabilities - of multi-channel receivers can mitigate that somewhat by HP filtering the mains or surround channels to well in the low 100s of Hz, but that runs the risk of localizing lower mid-bass. For 2-channel audio only using FRangers, I'd definitely be inclined to HP them, anywhere between 200-320, and go stereo with the woofers. If full-torque heavy lifting for those 16ft organ pedals, etc is required, dedicated subs (atmosphere generators) should be the weapon of choice.
The natural tendency would be to turn up the wick a little bit more, and the FR drivers can easily be driven past their comfortable operating area. The bass management - and in some cases bi-amping capabilities - of multi-channel receivers can mitigate that somewhat by HP filtering the mains or surround channels to well in the low 100s of Hz, but that runs the risk of localizing lower mid-bass. For 2-channel audio only using FRangers, I'd definitely be inclined to HP them, anywhere between 200-320, and go stereo with the woofers. If full-torque heavy lifting for those 16ft organ pedals, etc is required, dedicated subs (atmosphere generators) should be the weapon of choice.
sorta my point, actually
I must say that after the last couple of films at the Nat Geo IMax, with all 12 channels of surround sound and lots of big subs capable of doing pretty good justice to a Space Shuttle lift off, a few 8s with 100W behind them seems like pretty weak tea - but not all of us can afford the size of room required.
I must say that after the last couple of films at the Nat Geo IMax, with all 12 channels of surround sound and lots of big subs capable of doing pretty good justice to a Space Shuttle lift off, a few 8s with 100W behind them seems like pretty weak tea - but not all of us can afford the size of room required.
here's as good a place as any
TLS.org | Passive Line-Level Crossover
and for BSC
Passive Line Level Baffle Diffraction Step Compensation
TLS.org | Passive Line-Level Crossover
and for BSC
Passive Line Level Baffle Diffraction Step Compensation
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