Hi-
Is any one familiar enough with SL's Orion design to comment on what effect one might expect if one used a higher-powered set of amps. He suggests that expensive amps will not add to the sound, and recomends 60 watts per channel times 8 chennels. But I can not help but wander what would happen if 150 watt amps are used... I was looking at the Bryston 5 channel THX. These would probably work great as 2 of them would yeld the needed 8 chennals plus 2 more for a pair of the Thor subs
. My thinking is that by using a higher power amp, most "normal" work will be done within the bottom 30% of the amp's output, allowing for lower distortion and strain. I know this is a highly unsientific line of reasoning but I would love to hear some comments anyway.
Is any one familiar enough with SL's Orion design to comment on what effect one might expect if one used a higher-powered set of amps. He suggests that expensive amps will not add to the sound, and recomends 60 watts per channel times 8 chennels. But I can not help but wander what would happen if 150 watt amps are used... I was looking at the Bryston 5 channel THX. These would probably work great as 2 of them would yeld the needed 8 chennals plus 2 more for a pair of the Thor subs
. My thinking is that by using a higher power amp, most "normal" work will be done within the bottom 30% of the amp's output, allowing for lower distortion and strain. I know this is a highly unsientific line of reasoning but I would love to hear some comments anyway.amo said:
Having an amp with more power than the suggested 60watts/8Ohm will give you:
- up to 5 dB more SPL in the 50...100Hz range
- a higher risk of destroying your speakers
See: Linkwitz on max. dipole SPL
There's no need to worry about the amplifiers linear or non-linear distortion. Any "reasonable" amp will have distortions that are at least two orders of magnitude (factor 100) lower than the speaker's distortion.
Thomas
You should have no problems with the Bryston amps as long as you don't run at silly volumes. What blows up 90% of drivers is amplifiers driven into clipping. Just about every speaker I have is driven by an amp bigger than the speaker is rated for, and I have never lost a driver because of this.
Bigger amps will also give you more headroom for transient peaks.
Bigger amps will also give you more headroom for transient peaks.
I'm with pinkmouse on this one
I am also in agreement with Pinkmouse that driver damage is more likely to occur from driving a SS amp into clipping than from having more power on tap.
My general rule of thumb has been that you're better off overpowered than underpowered - Particularly with SS.
If you listen at reasonable levels the higher headroom usually means cleaner sound.
go for it and let us know how they sound.
regards
Ken L
pinkmouse said:
I am also in agreement with Pinkmouse that driver damage is more likely to occur from driving a SS amp into clipping than from having more power on tap.
My general rule of thumb has been that you're better off overpowered than underpowered - Particularly with SS.
If you listen at reasonable levels the higher headroom usually means cleaner sound.
go for it and let us know how they sound.
regards
Ken L
Im eventually going to build a pair myself and contemplated the same power question. But I think SLs' qoute speaks for itself:
"The higher power amplifier has the potential to bottom out and damage the woofers below 40 Hz and to overheat midrange and tweeter at excessive volume levels. The extra volume capability around 40 Hz can only be used with caution. I find that it exceeds what I would use for normal listening to various types of music in my large size living space. For these reasons I consider the AT6012 of Opt 01 a better match for the ORION. "
-which has 60 wpc. I think that the ordinary distortion distroying problem due to low wattage isnt an issue with a woofer used in this dipole situation as is too much power allowing too much excursion. I think its a way of helping you keep your foot off the gas pedal and preserving the drivers. If more volumn is needed, the Phoenix will provide more dbs but apparently with less finese.
But thats just my take. Good luck.
amt
"The higher power amplifier has the potential to bottom out and damage the woofers below 40 Hz and to overheat midrange and tweeter at excessive volume levels. The extra volume capability around 40 Hz can only be used with caution. I find that it exceeds what I would use for normal listening to various types of music in my large size living space. For these reasons I consider the AT6012 of Opt 01 a better match for the ORION. "
-which has 60 wpc. I think that the ordinary distortion distroying problem due to low wattage isnt an issue with a woofer used in this dipole situation as is too much power allowing too much excursion. I think its a way of helping you keep your foot off the gas pedal and preserving the drivers. If more volumn is needed, the Phoenix will provide more dbs but apparently with less finese.
But thats just my take. Good luck.
amt
Duuhhh, Well
amt makes some excellent points here.
I would like to state that my comments were meant from a frame of reference of general terms and was not taking special considerations of the Orions into account.
regards
Ken L
amt makes some excellent points here.
I would like to state that my comments were meant from a frame of reference of general terms and was not taking special considerations of the Orions into account.
regards
Ken L
The other advantge of the 6012 is that you can use a channel for each bass driver, making a total of eight channels of amplification, which is what SL recommends.
If you want an alternative 6 channel amp for not much money, a used Parasound 6 channel would be ideal, either 806 or the 1206.
This is especially good if you plan on an Orion variation using a digital crossover as they have volume controls for each channel so you maximise the gain structure for the crossover.
Steve
If you want an alternative 6 channel amp for not much money, a used Parasound 6 channel would be ideal, either 806 or the 1206.
This is especially good if you plan on an Orion variation using a digital crossover as they have volume controls for each channel so you maximise the gain structure for the crossover.
Steve
One of the reasons I brought this up is because the individual drivers are all rated substantially higher then 60 watts. One way to look at it, however, is that these ratings are meant as "...in a 3-way system, with passive crossovers, where the entire system shares this much power, not just this driver...". But, if each driver can handle more power then I do not see the point of not using it. I also do not understand tl's comments because I thought more mid and treble can be squized out... From what tl is saying, the entire system would just go out of alignment with a 5 db peak in the 50 to 100 hz range... I guess I just do not understand how amplification really works...
Because there seems to be some interest on the Orion, I have another, more theoretical question: What happens when 2 pairs of the Orion are placed in the same room? This of course would be a large room. First, the two left towers are placed next to each other, and so are the two right ones. If not, then one can be placed close to each corner (3 feet away). This is for situation where precise imaging is not vital, but more volume is required...
Thanks!
Because there seems to be some interest on the Orion, I have another, more theoretical question: What happens when 2 pairs of the Orion are placed in the same room? This of course would be a large room. First, the two left towers are placed next to each other, and so are the two right ones. If not, then one can be placed close to each corner (3 feet away). This is for situation where precise imaging is not vital, but more volume is required...
Thanks!
I'd put them in the 4 corners of the room (or thereabouts). You could use them for multichannel surround sound at sane volume levels or use the "all channel stereo" mode for loud parties. While you're at it, might as well add a 5th one for a center channel.
Since you do DIY already and you managed to put the X-O together, a chip amp such as SL recommends for the Phoenix offers the cheapest and most versatile solution. See "chip amps:, "gainclones" on this forum.
I did that for my Linkwitz type dipoles, using OPA548. Advantage, you get it so cheap that you get a very decent solution right away and still can experiment with different amps later on.
I do that now, and built an Aleph for my midrange. I find the Aleph more pleasant.
If you build separate PSU's for the chips (recommended, to isolate the effects of different current draws in the different bands) you can even recycle the PSU for any new amp topology that you try downstream. Only the PSU costs real money, the chips sell for dollars, and even an Aleph circuit minus PSU can be built for sub-$20.
I did that for my Linkwitz type dipoles, using OPA548. Advantage, you get it so cheap that you get a very decent solution right away and still can experiment with different amps later on.
I do that now, and built an Aleph for my midrange. I find the Aleph more pleasant.
If you build separate PSU's for the chips (recommended, to isolate the effects of different current draws in the different bands) you can even recycle the PSU for any new amp topology that you try downstream. Only the PSU costs real money, the chips sell for dollars, and even an Aleph circuit minus PSU can be built for sub-$20.
Amo, If you looking for high spl then as mentioned above, the Phoenix may be a better bet. It uses a total of 4 8" mids instead of 2 and 4 12" bass drivers instead of 10"ers. The cost of building 4 Orions for a possible/slight gain over 2 Phoenix units may be quite considerable. If you are serious about this, e-mail Mr. Linkwitz and ask his opinion. He is very accessible and interested in dipole discussion and implementation. If you do, let us know the particulars.🙂
amt
amt
I suspect if you put Orions side by side you'd get various weird cancellations and comb filtering effects.
If you need more volume SL recommends a Phoenix or Audio Artistry Beethoven style speakers, ie a MTMWW tower with separate subs.
Cheers
Steve
If you need more volume SL recommends a Phoenix or Audio Artistry Beethoven style speakers, ie a MTMWW tower with separate subs.
Cheers
Steve
MBK said:
I wish that I could agree with your assumption. Unfortunately, I can not. At this point I am only trying to understand weather or not to build the Orion, or some other system.
...
The Orion drivers are excursion limited at lower frequencies that are still musically important.
For example, assuming an 8.5" dipole path difference (the wings are curved and basket structures affect things so this is hard to figure) at its 120Hz cross-over frequency the mid-range runs out of xmax at 99dB (105dB total output). An amp delivering 70W into 8 Ohms will get you there.
With the 15" H-frame depth Siegfried uses in his examples, the woofers don't run out of excursion until they hit 118dB @ 80Hz, but are down to 100dB @ 40Hz and 82dB @ 20Hz.
There's no peak - more power just gives you more output before you clip the amp or bottom the speakers in that frequency range.
Basically, output can be limited by amplifier current, amplifier voltage (impedance increases as you approach resonance, so curent demands are minimal), or excursion (without a port/passive radiator, excursion increases 4X with each octave you go lower, resulting a 12dB/octave decrease in excursion limited output). IOW, maximum output is frequency dependant.
Dipoles complicate things more because of a 6dB/octave roll-off which is compensated for in active cross-overs with a signal boost. In the frequency range of interest, you're not yet excursion limited and that boost is enough to clip the low powered amp.
You'll get 6dB more output at lower frequencies, and 3dB at higher ones. There will be lobing problems and you probably won't be happy.
The midrange output limits can be raised with a higher XO frequency, which will make the limit Pmax instead of Xmax and reduce losses to the 6dB/octave dipole equalization. An MTM setup like Steve's will give you 6dB.
Woofer output can be increased by crossing over to separate sub-woofers, with a 40Hz LR4 XO giving you 6dB @ 40Hz and potentially a lot more in the last octave. You can also run higher displacement drivers like Steve's DPL12s (see Monte Kay's slanted driver H-frames to fit some 12" drivers in an Orion width baffle so polar response isn't affected).
Steve, just like to make you aware of this. Bob's design idea- a cross between Phoenix and Orion are like my speakers that I'm on the finishing stages of. I would like to chat with you sometime perhaps...MSN?
About the topic, for more power, I'd say go ahead. Agreeing with what is previously mentioned, more for SS amps seems better than less. Also, if a driver blows because it has reached passed it's maximum excursion (driven past so to speak), then it is not our problem, correct?
I would suspect that amo wouldn't be dumb enough to blow up his brand new Orion speaker.
About the topic, for more power, I'd say go ahead. Agreeing with what is previously mentioned, more for SS amps seems better than less. Also, if a driver blows because it has reached passed it's maximum excursion (driven past so to speak), then it is not our problem, correct?
I would suspect that amo wouldn't be dumb enough to blow up his brand new Orion speaker.
Bose(o) said:
Bose, I'm also building a cross between the Orion and Phoenix. At this point I have a pair of Phoenix woofers using the Madi 1252 drivers, and a small main dipole panel using one Vifa MG22 mid and probably the Seas 27TDFC tweeter. Crossover is basically Phoenix, but I might change the woofer to mid to 4th order, depending on whether the single MG22 can handle it or not. Or I might add a second MG22 and make the main panel an MTM. Basically a less expensive Phoenix.
I'm in Toronto. I'd like to hear about your project, you can email me at ron.steinberg@sympatico.ca
Cheers,
Ron
sfdoddsy said:
I would have to agree that side by side is probably a bad idea. What about integrating (building) the two Orions so that it becomes WMTMW where each W is a dipole. The second T can be ommited, but maybe not? The Orion sounds like a great design, I just do not want to start on something and then realize I do not have enough output. I rather have a baffle that is 1/2 loaded for some time...
Thanks!
As I mentioned above, Linkwitz recommends an MTMWW configuration with separate sub towers, as used in the Audio Artistry Beethove, crossovers at 1400, 300, 80, using two 8 inchers and two ten inchers. Probably 4 x 12 for the subs.
If you need even more, he designed the Beethoven Grand with WWMTMWW and the appripriate sub towers.
http://www.linkwitzlab.com/B-Grand.htm
In all cases the tweeter is kept at ear level, dictating the driver layout.
The real limitation on volume is the lower end of each driver's range. It is possible to improve on the capabilities of the Orion by changing to 12 inch drivers, such as the DPL12s I use, or the Stryke AV12s. If you need more, you'd need separate sub towers.
Or, as SL currently recommends, use monopole subs below your rooms resonant frequency, usually around 40Hz.
Cheers
Steve
If you need even more, he designed the Beethoven Grand with WWMTMWW and the appripriate sub towers.
http://www.linkwitzlab.com/B-Grand.htm
In all cases the tweeter is kept at ear level, dictating the driver layout.
The real limitation on volume is the lower end of each driver's range. It is possible to improve on the capabilities of the Orion by changing to 12 inch drivers, such as the DPL12s I use, or the Stryke AV12s. If you need more, you'd need separate sub towers.
Or, as SL currently recommends, use monopole subs below your rooms resonant frequency, usually around 40Hz.
Cheers
Steve
sfdoddsy said:
I absolutely agree on seperate sub towers, especially if you are going open baffle and need to match the output of 2 x 8inch mids! However, I recall from somewhere in his Foenix FAQ, he ok's the use of 2 tens below and 2 tens above the MTM baffle. He probably was thinking of one of his AA designs when he said this, but naturally, I can not help but to extend this to the Orion. Maybe I am totaly off path here, but the idea is to leave to Orion XO as is, simply double up on all the drivers except the tweeter, and do the WMTMW config where each W is the 10 in dipole. The separete open baffle subwoofer tower (something like 4 x 15 or 4 x 18 would be nice!) will complement the lowest frequencies. Or maybe, something like the THOR xo can be used to cut the lowest stuff from the Orion woofers completely, making this a 4 way open baffle design... Please comment. Thanks!
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