i would also like to see how they compare to the GPA416 in measurement and subjective listening impressions.
i have the 416 and consider building a box for them but i am very undecided if i should go with a simple sealed and subs below or resistive vent , AP , or even BR .
using two 416 looks like a good option too , decisions , decisions
That's parameter fitting to a model, right, not direct measurement of the T-matrix, which was what I was thinking about. But given a good model, this is, as you say, probably good enough.
I'm not home until Wednesday, so this is all fine with me. If you put a note here when you are ready, we can continue in the new thread.
Strange. It loads fine in IE for me. But I can update the site SW and see if that helps. And, you know, it's not that much work to try another browser
I like to have a couple installed, because some sites do not work well with one or the other. IE usually works, though.-Bjørn
Agreed that I haven't had chance to listen to these amps ! ;o)
I also would not fall into an easy generalisation of all SS amps sounding the same - far from it .
What I can offer is some experience of the Passlabs F4 ( which I built ) and the F5 ( which I have heard several times on good equipment at our UK meetings ) . I built the F4 with high hopes, and good components , but it falls short of what I can easily get from valve amps , from the midrange upwards. Lower down, it is fine, and spacious too, like a zero-feedback valve amp. From the mids up, the tone starts to 'grey' and the detail and definition of transients doesn't match what you get from SET or PP amps like Lynn's . From what I've heard, I think the F5 is slightly better in these areas than the F4 .
These two amps are however the best I've heard ( among quite a few ) in our DIY meetings , except that there's one guy who brings a germanium-based amp along, that sounds somewhat cleaner in the treble ( although the circuit probably needs more work to take out some 3rd/5th harmonic, to my ears ) .
So, if you have a comparison against either of the Passlabs amps, or the F2 which I've also heard , this would be good to know . I have heard the F4/5 criticised from the point of view of the driver stage , by a commercial UK designer . Both are of course Mosfet-based on the outputs, which is not ideal .
If anyone asks me which amp I've heard has the best dynamics and bass tone, then it would be the 'Aurora' amps I built back in 2003 with VV32B's, to Lynn's earlier PP design . The only reason I don't run an amp like that now, is that I slightly prefer the residual distortion spectrum of an SE amp ( although I'm sure the Karna gets very close ) , and I find I can get about 80-90% of the dynamics and bass tone of the PP amps by using a valve shunt-regulated power supply ( in my case a variant of the Bench/Broskie 'T-Rex' design ) .
I wasn't anticipating you'd need to have a fully-sorted crossover in order to judge this aspect. All I would do, if I had both drivers,would be to play each driver ( on the horn ) either unfiltered or with a simple high-pass , at low to moderate listening level , and just listen to how it renders small info 'between the notes' and how much of an 'aura' of sound/tone there is around the horn, on acoustic recordings. Mono is enough to do this too .
Having said that, I know it is a significant amount of work to interrupt what you're doing and mount up the other ( three-bolt ! ) driver onto the Azura and do this, when you already have a busy schedule of work planned . No probs !
Perhaps Lynn can comment on the low-level sound of the ceramic Radian 745 vs. the Neo one ? I only ask because it was the one concern CV had when I spoke to him on the phone a week ago .
It's not really urgent, as it'll be at least 6 months before I could order a pair of the Neo-Be's even if I can sell some 'stuff' to fund it !
The only thing clear from that post is the appalling manners.
If I get the gist, POOH feels we need to reproduce live sound levels in the home in order for there to be realism. Well, I think the volume needs to be scaled to the space. A full orchestra is simply not going to be reproduced spatially in an average listening room. In those circumstances less than live volume levels actually sound more realistic (to me).
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Agreed.
On top of that, the SPL is by no means the only factor that relates to the sense of realism in music reproduction.
I guess I posted too soon about 132 dB and 1600 watts. My apologies. Here's how discerning audiophiles do it.
My favorite quote in the article: "If we ran the system at its full capacity, people would die. People's ears would literally be bleeding." Good to know that legendary audio engineer, John Klett, has his musical priorities straight.
POOH, I'm sorry the referenced system doesn't have enough horns, and probably isn't loud enough. Maybe you can write a letter to Mr. Klett and share your wisdom and experience with him. Perspective is everything.
My favorite quote in the article: "If we ran the system at its full capacity, people would die. People's ears would literally be bleeding." Good to know that legendary audio engineer, John Klett, has his musical priorities straight.
POOH, I'm sorry the referenced system doesn't have enough horns, and probably isn't loud enough. Maybe you can write a letter to Mr. Klett and share your wisdom and experience with him. Perspective is everything.
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If you go with the 745 Neo Al you could upgrade to Be diaphragm as it is retrofittable. If we get the low level thing answered and we had a step test off the AZ425, then it is pretty much there.
You may also need a supertweeter.
Delusion charms:
Reality:
"By having an incredibly powerful system that's not being run anywhere close to capacity (Dewaele said it was run at around 20 percent), but with the full range of EQ and dynamics of the tracks, the experience is radically different. "There is tons of headroom. It's very clean, very relaxed. You are subjected to sound pressure levels that are really up there, but it sounds so clean and free of stress that you don't perceive it to be loud. You are awash with sound," says Klett"
This is not your Beyond the Aerial perspective as in your perspective is not to recreate live music, it is to follow in steps of high end audio foolish progression as in "dead end" "do again"
Reality:
"By having an incredibly powerful system that's not being run anywhere close to capacity (Dewaele said it was run at around 20 percent), but with the full range of EQ and dynamics of the tracks, the experience is radically different. "There is tons of headroom. It's very clean, very relaxed. You are subjected to sound pressure levels that are really up there, but it sounds so clean and free of stress that you don't perceive it to be loud. You are awash with sound," says Klett"
This is not your Beyond the Aerial perspective as in your perspective is not to recreate live music, it is to follow in steps of high end audio foolish progression as in "dead end" "do again"
I too am curious what your examples measured in terms of thiele/small #s. All the talk of ultra-low Q for the 515 AlNiCo is at odds with the published numbers from GPA. Any light you could shed on the topic would be appreciated.
GPA 515C Spec Sheet
Regards,
John
DrBoar,
When you think about trying to reproduce the sound and impact of those drums you were just talking about that is where the problems of reproduction in a small space come into play. It really doesn't matter if you are using direct radiators or horns when producing sound of that level and intensity, you have another problem. That problem as I see it is the decay rate and the attenuation that you only get with distance and space. How can you create that sound level and have anywhere near a realistic decay profile in a small room, for that matter you can't have the attenuation of distance either. So to me nothing in a small room can create the sound field or the dynamic impact that you get in a large space, the bass response will get muddy at some level in a small room due to the fact that you just don't have the quick decay profile you would have in a very large space. Perhaps this is why so many us a high pass filter on the low end of there audio systems, to remove these low frequencies that so soon get out of control.
When you think about trying to reproduce the sound and impact of those drums you were just talking about that is where the problems of reproduction in a small space come into play. It really doesn't matter if you are using direct radiators or horns when producing sound of that level and intensity, you have another problem. That problem as I see it is the decay rate and the attenuation that you only get with distance and space. How can you create that sound level and have anywhere near a realistic decay profile in a small room, for that matter you can't have the attenuation of distance either. So to me nothing in a small room can create the sound field or the dynamic impact that you get in a large space, the bass response will get muddy at some level in a small room due to the fact that you just don't have the quick decay profile you would have in a very large space. Perhaps this is why so many us a high pass filter on the low end of there audio systems, to remove these low frequencies that so soon get out of control.
Cheers - good point on the replaceable diaphragm .
Tweeters - have Aurum G3 and B&C DE35 to work with - so far, the G3 sounded better , but can go through a few more experiments on those .
Why do some here believe that you would require a super tweeter above the Radian Be 745 driver? Is this because you don't think you can eq the response curve flat or the inevitable high frequency beaming that most horns and waveguides produce if the lower cutoff frequency is on the low side of things? Would you also require these supplemental high frequency devices if you were using the TAD 2001 or is it just the Radian that makes so many assume this?
20% of 50,000 watts from any class D amp is like thinking of sea water being drinkable.
You could get enough watts together you could talk to Mission Control directly from the Shuttle. There's a first
Comparing with direct drivers I would say a tweeter is not mandatory, judging by the good form of the roll off. And any tendency to beam could compensate for this droop at least on axis.
It's not mandatory, but preferable when you sit down and compare the two. I have Radian 750-8 alu, and it reaches to about 15-16 000Hz before it fades out. In smaller horns the Radians have better treble but less midrange of course. Perhaps the Be reaches a little higher. Some say alu has better tone than Be, but I don't know.
Rembember, it is pretty logical that a horn tweeter needs a tweeter sized horn, not a midrange sized horn. If you use a midrange horn for your tweeter, you will miss out on a lot of good stuff. If you insist on using Radian 745 Be all the way up, then get another pair of Radian 745 Be with smaller horns. And then you add another small ribbon driver horn with a Raal or a Transmission Audio ribbon! Then you are broke.
Rembember, it is pretty logical that a horn tweeter needs a tweeter sized horn, not a midrange sized horn. If you use a midrange horn for your tweeter, you will miss out on a lot of good stuff. If you insist on using Radian 745 Be all the way up, then get another pair of Radian 745 Be with smaller horns. And then you add another small ribbon driver horn with a Raal or a Transmission Audio ribbon!
Then you are broke.
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I like to get my reality from acoustic transducers in form of expanding horn transformers producing acoustic watts with as little compromise as possible not cheap switching devices.. Sea water is drinkable and so is the "high end" charm both have similar results for the deserving consumer.