Are any completely built speakers using Purifi drivers commercially available at this time? If so which is the best one?
There is also these two by Joachim Gerhard.Are any completely built speakers using Purifi drivers commercially available at this time? If so which is the best one?
I have a design sold my Jim Salk--the BePure2. https://salksound.com/model.php?model=BePure+2Are any completely built speakers using Purifi drivers commercially available at this time? If so which is the best one?
I have a design sold my Jim Salk--the BePure2. https://salksound.com/model.php?model=BePure+2
Floorstanding design allowed to make proper vertical port?I have a design sold my Jim Salk--the BePure2
Floorstanding design allowed to make proper vertical port?
I'd like to see impedance graph or at least know impedance minimum. Pair of such powerful motors might make this "easy load" not so easy ...
That looks like a big gap between the tweeter and lower woofer, is this really just a 2-way and not a 2.5-way?I have a design sold my Jim Salk--the BePure2. https://salksound.com/model.php?model=BePure+2
Good observation and good question. It's a 2.0. That does make the listening distance a little more critical. If you listen at, say, 1 meter, there will be a dip around 2 kHz. At the design distance of 3 meters or greater, that smooths out. I've done 2.5's, and I've never been as happy with the midrange performance. They're certainly trickier to pull off than a simple 2.0.That looks like a big gap between the tweeter and lower woofer, is this really just a 2-way and not a 2.5-way?
Dennis thanks for your time and reply. Are both the active woofers or is the bottom the Purifi passive radiator? If they are two active drivers do both see the same response from the crossover or is the bottom woofer crossed lower? ThanksGood observation and good question. It's a 2.0. That does make the listening distance a little more critical. If you listen at, say, 1 meter, there will be a dip around 2 kHz. At the design distance of 3 meters or greater, that smooths out. I've done 2.5's, and I've never been as happy with the midrange performance. They're certainly trickier to pull off than a simple 2.0.
Jim used a very long, wide port, which the Purifi responds to well. The factory passive radiators tune too low with just one woofer, and get expensive with two woofers, since you may have to use as many as four of them. In any event, the impedance is an easy load for any amplifier designed for 4 Ohms.Floorstanding design allowed to make proper vertical port?
I'd like to see impedance graph or at least know impedance minimum. Pair of such powerful motors might malke this "easy load" not so easy ...
Both woofers are active--it's a simple 2-way. No passive radiators involved--just the big port I mention in my other post.Dennis thanks for your time and reply. Are both the active woofers or is the bottom the Purifi passive radiator? If they are two active drivers do both see the same response from the crossover or is the bottom woofer crossed lower? Thanks
Thank you Dennis. That explains the higher efficiency rating using two of the woofers.Jim used a very long, wide port, which the Purifi responds to well. The factory passive radiators tune too low with just one woofer, and get expensive with two woofers, since you may have to use as many as four of them. In any event, the impedance is an easy load for any amplifier designed for 4 Ohms.
View attachment 169975
Both woofers are active--it's a simple 2-way. No passive radiators involved--just the big port I mention in my other post.
Jim used a very long, wide port, which the Purifi responds to well. The factory passive radiators tune too low with just one woofer, and get expensive with two woofers, since you may have to use as many as four of them. In any event, the impedance is an easy load for any amplifier designed for 4 Ohms.
View attachment 169975
Both woofers are active--it's a simple 2-way. No passive radiators involved--just the big port I mention in my other post.
It's closer to 3.5 Ohms minimum, which is what you generally get running two nominal 8 Ohm speakers in parallel. The tuning point is pretty clearly 30 Hz, which is what we were aiming for. I checked for port resonances, and they're well down, and the port is on the back. There really aren't any issues here.So, the box is tuned to 25 Hz. Impedance is 3 ohms from 150 to 500 Hz, so may be challenging for lesser amps/AVRs. If am spending greater than $6K, can probably afford a robust amp.
The port tuning appears even lower (off the graph)? With a long port, will be hard to avoid port resonance(s) without some tapering, lining, etc. Based on modeling, is still tricky tuning for bass reflex, but still should be better than SPK5.
So Dennis are the drivers as good as all the hype they have received?It's closer to 3.5 Ohms minimum, which is what you generally get running two nominal 8 Ohm speakers in parallel. The tuning point is pretty clearly 30 Hz, which is what we were aiming for. I checked for port resonances, and they're well down, and the port is on the back. There really aren't any issues here.
Oops, misread the scale, the minima clearly is 30 Hz. See no point in hair-splitting over .5 ohm.It's closer to 3.5 Ohms minimum, which is what you generally get running two nominal 8 Ohm speakers in parallel. The tuning point is pretty clearly 30 Hz, which is what we were aiming for. I checked for port resonances, and they're well down, and the port is on the back. There really aren't any issues here.
Yes and no. They do what is claimed, but it's a highly specialized driver. It basically either needs a passive radiator in a bookshelf application, or a very large port in a tower. And it has to be crossed low (1900 Hz is about it) in a 2-way. And it's ugly. The venerable Scan Speak 7" Revelator is a much more versatile unit. It's high end response is much smoother and extended, it works with reasonable sized ports, and it's distortion is almost as low as the Purifi's at most volume levels. Plus, it's cheaper and more attractive.So Dennis are the drivers as good as all the hype they have received?