Good advice and although I don't show my work here, I spend lots of time investigating the theoretics of certain layouts. So that gives a good estimation of figures if not sound.
As is the case with the Tumult, great driver but it can certainly be bettered with additional thinking. As I've already stated I like the XBL2 sound but its not the end of the search.
I'm not in a position to buy yet anyway so I'm in no rush.
thylantyr said:I seriously doubt the QSC would offer an improvement over the P101.
Sounds like a cool challenge. The 200w P101 vs. the 4000w QSC
or do you want to challenge the 9000w QSC?
Ugh, not another one who judges amps on power output alone surely!
Doesn't SQ matter here? The QSC is OK but its hardly a Bryston or Krell is it? I've heard a QSC 2540 and Behringer EP2500 both were OK but not brilliant, I prefered the QSC though. My comments are here:
http://www.diyaudio.com/forums/showthread.php?postid=613150#post613150
You think that the XLS or Volt drivers I'm looking at needs that much power? What about bridging P101's?
Sorry but it sounds needless to me. Fine if you've got subs rated to 1600w, I agree more power is needed than the P101 provides. However 200w into 8ohm or 380w into 4ohm is more than enough for the XLS, Volt etc.
Stuff like the Diamond are DVC so power could be bumped up to around 800w into 4ohm simply by using a dedicated amp for each coil. Or with bridging I'd be looking at 1600w into 4ohm.
First thing I did.
I'd like around 100ltr NET max. Two boxes positioned next to the mains.
Room is 28ft x 22ft x 9ft/12ft(the roof slopes from 12ft to 9ft)
flat 15hz is overkill for music but for HT I'd say essential for the full effect and that's why. This is an AV setup.
The DIY amps are much cheaper to build since I've got half the bits already for the another 6 x P101's and I've got 6 x already built.
I've also got all the components for the Krell's, I'm just waiting on the PCB's.
The AKSA 55's are around $430AUS for a complete ready to go stereo pair.
I have a Mackie HRS120 sub which features a PR as well as Servo feedback.
Ugh, not another one who judges amps on power output alone surely!
All differences aside, to drive subwoofers you need power.
Lets assume that someone has a magical SQ tube amp
rated at 10 watts. This amp will not even bring a beer to the
party when driving subwoofers whereas the QSC will provide
what the woofers need -> power.
I would not run the PL series full range as it's an H bridge output stage. I would run class AB outputs full range regardless if
QSC makes the amp or Krell. The modern amplifier is not
designed to perform bad whether it's pro audio or home audio.
You'd be surprised to know that there are many audiophile
type of pro audio people who are picky about SQ too. Don't
stereotype that industry as designing bad amplifiers. Audio
amplification design is easy and a mature industry.
I've heard a QSC 2540 and Behringer EP2500 both were OK but not brilliant, I prefered the QSC though. My comments are here:
I have a 2450 and I'd sell my Adcom home amp with no hesitation
to get another QSC. It's a great amp for the money. I would
prefer to use something bigger to drive a subwoofer array, the
4kw or 5kw amp, the PL series optimium. Also look at Crown.
I also know what the difference is between EP2500 and QSC
2450. The EP is over-rated in specs, less power in real life due to
the smaller transformer. But it cost 1/2 the price.
You think that the XLS or Volt drivers I'm looking at needs that much power? What about bridging P101's?
You need to operate one P101 per woofer. Lets assume you
need ten XLS woofers. You need ten P101 amplifiers to ensure
each woofer gets 200w. If you want more power, then you
have to bridge the P101's, so you now have 20 amplifiers to
deal with. How much will this cost vs. a big monster pro amp?
You don't have to limit yourself to just one proamp either,
get two or three -- haha.
I'm looking at the P101 design right now. This is a simple design,
not very robust with two transistors per rail. I took a similar
design over 15 years ago and modded the amp with more
output transistors, eight per rail and placed them on a massive
heatsink with a 1/4" aluminum base plate, T0-3 transistors.
I think I had 200,000uF of capacitance per rail and used 2KVA
transformer. I had to mount the predriver transistor on the heatsink because they ran hotter and I reduced amplifier gain
because it was to hissy for my liking. I installed a 5532 opamp
on the front end to feed the amplifier a large voltage to drive it to
full power to offset the reduced gain. The net result was a less
hissy amp, you could place your ear on the tweeter and not hear
hiss. /sweet.
I drove 1/2 ohm per channel playing test tones with this amp on
two house circuits. The point is, that P101 has mod potential
because it also uses lateral mosfets. You can parallel a few more
transistors on each rail without matching transistors like you do
with vertical mosfet... so you don't have to buy a ton of transistors to find matches.
Something more powerful than P101 is the Holton amplifier,
AV800, actually the modded AV800 1KW.
http://www.aussieamplifiers.com/av800.htm
10 transistor per rail for the 1kw module.
This is an advanced project as the documentation had errors,
I think I trapped all the errors and drew up my own set of
docs, but I haven't verified it. I notice Holton is changing his
business model, no longer offering plans on the website. Lucky
me I have them - harr harr harr.
For subwoofer only, it makes you wonder if it's even worth
making a class AB amp when there is 'digital' amplifier options
out there.
I worked on a PCB layout project taking the AV800-1KW design
and adding extra 'stuff'. I was my pet project for a while and it
has 14 transistors per rail on all on PCB.
Problem is. My layout is 4 layers, a big board and expensive to
fab. It would cost me $2k just to get a batch of PCB's made.
Another $2k-$3k to get a big chunk of awesome heatsink extrusion, the really good stuff. Factor in machining a chassis
to make the result look 'store bought' and the price tag rises
alot.
... then when I price a QSC 4kw amp for $1000, then why do I
want to mess around with DIY amps ? Prices of pro audio have
dropped, quality improved, and better designs can be had for
cheap. DIY amps are more of a novelty now, for the thrill of
making it not because there is huge savings like DIY loudspeakers.
If you can't afford an array of Tumult and the big QSC or Crown
amp then you have to settle for less and not have the ultimate.
Everyone wants to have the uber setup but it cost money unless
you steal.
The only way to keep your project cost down is to do what you
said. A stock P101 per woofer, or per coil, or bridged. It's
a good solution but you'll have alot of amplifier clutter when
all you may need is one or two big monster pro amps and they
are more feature rich than a bare bones P101. Clipping LED's,
protection circuits, etc.
All differences aside, to drive subwoofers you need power.
Lets assume that someone has a magical SQ tube amp
rated at 10 watts. This amp will not even bring a beer to the
party when driving subwoofers whereas the QSC will provide
what the woofers need -> power.
I would not run the PL series full range as it's an H bridge output stage. I would run class AB outputs full range regardless if
QSC makes the amp or Krell. The modern amplifier is not
designed to perform bad whether it's pro audio or home audio.
You'd be surprised to know that there are many audiophile
type of pro audio people who are picky about SQ too. Don't
stereotype that industry as designing bad amplifiers. Audio
amplification design is easy and a mature industry.
I've heard a QSC 2540 and Behringer EP2500 both were OK but not brilliant, I prefered the QSC though. My comments are here:
I have a 2450 and I'd sell my Adcom home amp with no hesitation
to get another QSC. It's a great amp for the money. I would
prefer to use something bigger to drive a subwoofer array, the
4kw or 5kw amp, the PL series optimium. Also look at Crown.
I also know what the difference is between EP2500 and QSC
2450. The EP is over-rated in specs, less power in real life due to
the smaller transformer. But it cost 1/2 the price.
You think that the XLS or Volt drivers I'm looking at needs that much power? What about bridging P101's?
You need to operate one P101 per woofer. Lets assume you
need ten XLS woofers. You need ten P101 amplifiers to ensure
each woofer gets 200w. If you want more power, then you
have to bridge the P101's, so you now have 20 amplifiers to
deal with. How much will this cost vs. a big monster pro amp?
You don't have to limit yourself to just one proamp either,
get two or three -- haha.
I'm looking at the P101 design right now. This is a simple design,
not very robust with two transistors per rail. I took a similar
design over 15 years ago and modded the amp with more
output transistors, eight per rail and placed them on a massive
heatsink with a 1/4" aluminum base plate, T0-3 transistors.
I think I had 200,000uF of capacitance per rail and used 2KVA
transformer. I had to mount the predriver transistor on the heatsink because they ran hotter and I reduced amplifier gain
because it was to hissy for my liking. I installed a 5532 opamp
on the front end to feed the amplifier a large voltage to drive it to
full power to offset the reduced gain. The net result was a less
hissy amp, you could place your ear on the tweeter and not hear
hiss. /sweet.
I drove 1/2 ohm per channel playing test tones with this amp on
two house circuits. The point is, that P101 has mod potential
because it also uses lateral mosfets. You can parallel a few more
transistors on each rail without matching transistors like you do
with vertical mosfet... so you don't have to buy a ton of transistors to find matches.
Something more powerful than P101 is the Holton amplifier,
AV800, actually the modded AV800 1KW.
http://www.aussieamplifiers.com/av800.htm
10 transistor per rail for the 1kw module.
This is an advanced project as the documentation had errors,
I think I trapped all the errors and drew up my own set of
docs, but I haven't verified it. I notice Holton is changing his
business model, no longer offering plans on the website. Lucky
me I have them - harr harr harr.
For subwoofer only, it makes you wonder if it's even worth
making a class AB amp when there is 'digital' amplifier options
out there.
I worked on a PCB layout project taking the AV800-1KW design
and adding extra 'stuff'. I was my pet project for a while and it
has 14 transistors per rail on all on PCB.
Problem is. My layout is 4 layers, a big board and expensive to
fab. It would cost me $2k just to get a batch of PCB's made.
Another $2k-$3k to get a big chunk of awesome heatsink extrusion, the really good stuff. Factor in machining a chassis
to make the result look 'store bought' and the price tag rises
alot.
... then when I price a QSC 4kw amp for $1000, then why do I
want to mess around with DIY amps ? Prices of pro audio have
dropped, quality improved, and better designs can be had for
cheap. DIY amps are more of a novelty now, for the thrill of
making it not because there is huge savings like DIY loudspeakers.
If you can't afford an array of Tumult and the big QSC or Crown
amp then you have to settle for less and not have the ultimate.
Everyone wants to have the uber setup but it cost money unless
you steal.
The only way to keep your project cost down is to do what you
said. A stock P101 per woofer, or per coil, or bridged. It's
a good solution but you'll have alot of amplifier clutter when
all you may need is one or two big monster pro amps and they
are more feature rich than a bare bones P101. Clipping LED's,
protection circuits, etc.
thylantyr said:Ugh, not another one who judges amps on power output alone surely!
All differences aside, to drive subwoofers you need power.
Lets assume that someone has a magical SQ tube amp
rated at 10 watts. This amp will not even bring a beer to the
party when driving subwoofers whereas the QSC will provide
what the woofers need -> power.
I would not run the PL series full range as it's an H bridge output stage. I would run class AB outputs full range regardless if
QSC makes the amp or Krell. The modern amplifier is not
designed to perform bad whether it's pro audio or home audio.
You'd be surprised to know that there are many audiophile
type of pro audio people who are picky about SQ too. Don't
stereotype that industry as designing bad amplifiers. Audio
amplification design is easy and a mature industry.
I've heard a QSC 2540 and Behringer EP2500 both were OK but not brilliant, I prefered the QSC though. My comments are here:
I have a 2450 and I'd sell my Adcom home amp with no hesitation
to get another QSC. It's a great amp for the money. I would
prefer to use something bigger to drive a subwoofer array, the
4kw or 5kw amp, the PL series optimium. Also look at Crown.
I also know what the difference is between EP2500 and QSC
2450. The EP is over-rated in specs, less power in real life due to
the smaller transformer. But it cost 1/2 the price.
You think that the XLS or Volt drivers I'm looking at needs that much power? What about bridging P101's?
You need to operate one P101 per woofer. Lets assume you
need ten XLS woofers. You need ten P101 amplifiers to ensure
each woofer gets 200w. If you want more power, then you
have to bridge the P101's, so you now have 20 amplifiers to
deal with. How much will this cost vs. a big monster pro amp?
You don't have to limit yourself to just one proamp either,
get two or three -- haha.
I'm looking at the P101 design right now. This is a simple design,
not very robust with two transistors per rail. I took a similar
design over 15 years ago and modded the amp with more
output transistors, eight per rail and placed them on a massive
heatsink with a 1/4" aluminum base plate, T0-3 transistors.
I think I had 200,000uF of capacitance per rail and used 2KVA
transformer. I had to mount the predriver transistor on the heatsink because they ran hotter and I reduced amplifier gain
because it was to hissy for my liking. I installed a 5532 opamp
on the front end to feed the amplifier a large voltage to drive it to
full power to offset the reduced gain. The net result was a less
hissy amp, you could place your ear on the tweeter and not hear
hiss. /sweet.
I drove 1/2 ohm per channel playing test tones with this amp on
two house circuits. The point is, that P101 has mod potential
because it also uses lateral mosfets. You can parallel a few more
transistors on each rail without matching transistors like you do
with vertical mosfet... so you don't have to buy a ton of transistors to find matches.
Something more powerful than P101 is the Holton amplifier,
AV800, actually the modded AV800 1KW.
http://www.aussieamplifiers.com/av800.htm
10 transistor per rail for the 1kw module.
This is an advanced project as the documentation had errors,
I think I trapped all the errors and drew up my own set of
docs, but I haven't verified it. I notice Holton is changing his
business model, no longer offering plans on the website. Lucky
me I have them - harr harr harr.
For subwoofer only, it makes you wonder if it's even worth
making a class AB amp when there is 'digital' amplifier options
out there.
I worked on a PCB layout project taking the AV800-1KW design
and adding extra 'stuff'. I was my pet project for a while and it
has 14 transistors per rail on all on PCB.
Problem is. My layout is 4 layers, a big board and expensive to
fab. It would cost me $2k just to get a batch of PCB's made.
Another $2k-$3k to get a big chunk of awesome heatsink extrusion, the really good stuff. Factor in machining a chassis
to make the result look 'store bought' and the price tag rises
alot.
... then when I price a QSC 4kw amp for $1000, then why do I
want to mess around with DIY amps ? Prices of pro audio have
dropped, quality improved, and better designs can be had for
cheap. DIY amps are more of a novelty now, for the thrill of
making it not because there is huge savings like DIY loudspeakers.
If you can't afford an array of Tumult and the big QSC or Crown
amp then you have to settle for less and not have the ultimate.
Everyone wants to have the uber setup but it cost money unless
you steal.
The only way to keep your project cost down is to do what you
said. A stock P101 per woofer, or per coil, or bridged. It's
a good solution but you'll have alot of amplifier clutter when
all you may need is one or two big monster pro amps and they
are more feature rich than a bare bones P101. Clipping LED's,
protection circuits, etc.
All valid points but I can't help feeling that much of it doesn't apply to me.
I haven't even decided on drivers yet but you almost assume massive power requirements that in-effecient subs such as Tumult require to get them to even f@rt.
You also assume that building DIY amps is expensive. Fact is I already have 6 x P101's and just need the traffo, PCB's and PSU caps for another 6. I work that out at around £200.
Casework is not needed since I plan to install the amps into the cabinet for the subs.
Project cost are important but since I've spent over $11,000 already including the PC XO, I'll do whatever else it takes. With the P101 I know they sound great, probably wasted just for subs if that's possible. I get to try these before I even think of buying a commercial amps simply because they are already there and are very compentant. The problem with the QSC or any amp is I'll need rackspace also, with the panels or PCB's I can mount to the subs without dissection.
There's a few other options too:
http://www.bkelec.com/Modules/bsbpv500.htm
http://www.bkelec.com/Modules/mf1000.htm
do me a favor shin and read my current plans for my subwoofer system from 40hz down where my midbasses are still flat and shine like the sun
http://www.diyaudio.com/forums/showthread.php?s=&threadid=63831
it's both cheap.... dynamic, loud, and esoteric
2 18" PR's is cool and is likely where my design will rest
it's a cheap $800 in parts build up since I have my amp... and it reaches levels in a room not corner loaded of 120db at 10hz with a gentle rise to the peak at 100hz....
much like a sealed setup but with about a 10000000x superior low end
this is of course to keep up with my mains which are capable of around 120db from 30hz-15khz at 60degree off-axis on the x AND y plane
just a thought
http://www.diyaudio.com/forums/showthread.php?s=&threadid=63831
it's both cheap.... dynamic, loud, and esoteric
2 18" PR's is cool and is likely where my design will rest
it's a cheap $800 in parts build up since I have my amp... and it reaches levels in a room not corner loaded of 120db at 10hz with a gentle rise to the peak at 100hz....
much like a sealed setup but with about a 10000000x superior low end
this is of course to keep up with my mains which are capable of around 120db from 30hz-15khz at 60degree off-axis on the x AND y plane
just a thought
Shin....
where do you buy Seas W's in th UK.....???
I am looking at the W22 and 18s for a possible project...
The W22 is close to 150£ locally here in Norway and appx 85£ at Madisound.... would you beleive it...???
EDIT.
silly me.. I didn't notice wilmslow had the Excel's listed separately!
where do you buy Seas W's in th UK.....???
I am looking at the W22 and 18s for a possible project...
The W22 is close to 150£ locally here in Norway and appx 85£ at Madisound.... would you beleive it...???
EDIT.
silly me.. I didn't notice wilmslow had the Excel's listed separately!
AuroraB said:
Wilmslow wouldn't be my first choice for value, they are very reliable and offer good advice but they have a large markup on some items.
I think wilmslow are charging something like £210 for a single W26!
Its cheaper to buy from Europe and pay a little more for shipping. Thanks to the EU we don't have to pay import duties.
Audiophilenoob said:
I've looked at thread and frankly your goals are laughable
Your trying to get 10hz flat at 130dB without EQ?
You NEED a transform circuit. Even with those weak L22's 4 x 8" in sealed cabs I could reach flat 18hz in room thanks to the tranform I built.
You dismiss the XXX based on Fs but what's that all about? With the transform you can lower the effective Fs and Q of the cabinet. Sure distortion increases as does power requirements but you substitute with what I've being saying all along whilst discussing subs, use multiple drivers.
BTW the XXX is great for HT and music but not as good as I'd like.
Again its all a trade off for acceptablility.
You ain't gonna get 10hz flat 120dB+ with a couple of 18's. You won't even get 10hz flat without massive and I mean massive TL enclosures. Even then output below Fs in TL's would mean you'd have a hard time to reaching that. With a transform its completely trivial to reach 10hz WITH the right subs but you need a sealed design to do this. Porting with transform is dangerous for your subs and never yields as good a result.
I blushed for you on that one.
Aren't you embarassed talking like that?
Come on get real and consider important factors that sealed offers. Namely Phase, GD and Energy/Time/Frequency spectrograms. They are inefficient for sure but from a SQ perspective a very well constructed sealed box with EQ offer the best results when it comes to infrasonic for the home environment.
Why is it a few people think TL's are the salvation in bass? They are at their most agreeable, I believe, when they cover anything less than infrasonic bass. The fact that to tune to 13hz with a TL means your looking at crazy huge line length's and cross sections.
You've got a choice - massive and I mean massive enclosures with a couple of drivers or sealed smallish enclosure with a fair few drivers and EQ to reach your goals.
I prefer the sound of a well designed sealed box, there's a real tightness to the sound and you get that stop start and nimbleness that's closer to the best servo's. With infrasonics I think because the cone of the driver is carrying so much energy the more damped they are the better. Acoustic suspension in otherwords. They seem to integrate better with the mains too but that's room dependant I suspect.
thylantyr said:
Lots of power is always nice with subs.
But its certainly not a must have for a very good sub.
The PMC XB3 is about the only TL sub I actually like:
An externally hosted image should be here but it was not working when we last tested it.
http://www.pmcloudspeaker.com/xb3.html
It needs very little power to perform well, CRTProjectors in the UK has one in their main demo room. It really is a surprising performer but you look at the size of it and its like a 2 seater couch! The line is nearly 5 meters long and it measure 1m x 0.8m x 0.45m. Again this illustrates you can trade size for efficiency.
The problem for me is I want or rather will have to settle for ineffecient meaning lots of drivers. The upshoot is great distortion specs and size. The downside is rather large amounts of amps and drivers.
PS. The driver in the XB3 is the superb 15" Volt Radial, great driver.
ShinOBIWAN said:
I've looked at thread and frankly your goals are laughable
Your trying to get 10hz flat at 130dB without EQ?
You NEED a transform circuit. Even with those weak L22's 4 x 8" in sealed cabs I could reach flat 18hz in room thanks to the tranform I built.
You dismiss the XXX based on Fs but what's that all about? With the transform you can lower the effective Fs and Q of the cabinet. Sure distortion increases as does power requirements but you substitute with what I've being saying all along whilst discussing subs, use multiple drivers.
BTW the XXX is great for HT and music but not as good as I'd like.
Again its all a trade off for acceptablility.
You ain't gonna get 10hz flat 120dB+ with a couple of 18's. You won't even get 10hz flat without massive and I mean massive TL enclosures. Even then output below Fs in TL's would mean you'd have a hard time to reaching that. With a transform its completely trivial to reach 10hz WITH the right subs but you need a sealed design to do this. Porting with transform is dangerous for your subs and never yields as good a result.
I blushed for you on that one.
Aren't you embarassed talking like that?
Come on get real and consider important factors that sealed offers. Namely Phase, GD and Energy/Time/Frequency spectrograms. They are inefficient for sure but from a SQ perspective a very well constructed sealed box with EQ offer the best results when it comes to infrasonic for the home environment.
Why is it a few people think TL's are the salvation in bass? They are at their most agreeable, I believe, when they cover anything less than infrasonic bass. The fact that to tune to 13hz with a TL means your looking at crazy huge line length's and cross sections.
You've got a choice - massive and I mean massive enclosures with a couple of drivers or sealed smallish enclosure with a fair few drivers and EQ to reach your goals.
I prefer the sound of a well designed sealed box, there's a real tightness to the sound and you get that stop start and nimbleness that's closer to the best servo's. With infrasonics I think because the cone of the driver is carrying so much energy the more damped they are the better. Acoustic suspension in otherwords. They seem to integrate better with the mains too but that's room dependant I suspect.
you obviuosly didn't read the progession of the thread
I'm reasearching an LT but there doesn't seem to be an advantage
right now the goal is 120db at 10hz flat to 124db at 40hz with EQ.... which is acheived
if you believe your sealed setup can do this by all means
the LT doesn't help much in my setup... but it's not like I'm not looking into it... if you think the LT's going to make those 8 10's iwth minimal excursion do 120db at 10hz with 2400 watts.... then show me some proof man.... it can't even do it with 8 12's and an LT.... I've been looking at this for an option... 8 AV12's.... about the same output as 4 15's isobarik ported....
it was suggested multiple times.... and I'm just trying to be helpful
if you think 8 10's = 4 15's isobarik in 15 cubes on the low end then well.... I'm sry but you're incorrect
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