Great paint on the green towers, is there a post I've missed on this build?
Those were Rory Buska's speakers, he said they were the last DIY build he completed, back in 2015. He mentioned the paint shop that did the work, but it wasn't something I am familiar with so I don't remember the name. But the picture isn't lying, the paint job was pretty impressive.
The Blue towers were I believe a pending or already released 3way CSS kit.
Steve Fishe in Tennessee painted the Iguanas when Rory (Buszka, btw) was at Thiel.
Rory I believe has shed all social media from his life. He still emails, but is not on FB or any forums any longer. This has been this way for a few years now.
I can tell you the drivers though. The Beston RT002 sealed back planar is the top-end. The midrange is the GRS Pioneer 4" replacement driver 4FR-8 in a sealed chamber. The the woofer is the GRS 8SW-4 Poly cone subwoofer in a vented box.
If you are really curious, I can see if he wants to pop in here and give more details...
Ben is right, I have shed social media from my life for my own reasons, apart from LinkedIn (which I visit infrequently but keep updated) but I also have not published very much on the Iguanas, because the reviews in different venues have been mixed. I have a pair of more technically perfect speakers in the house, which are Thiel CS1.7 towers, and of course I have the Neutrinos from 2012 which still make me very happy on my desk, but there are things the Iguanas do that make them probably the most 'fun' all-around speakers I have. They have elements of the 'three way sound' and also the lightning quick treble reflexes of a planar tweeter, along with good subjective speed and dynamics from the 4" mid, which is a GRS clone of an older Pioneer 4.5" full range speaker.
The bass section is maybe the weakest link in the speaker, although I think it's 'fine'; the GRS 8SW-4 is in a slightly under-sized (and thereby overdamped) bass reflex alignment to try to reduce peakiness due to the woofer's high Qts. It can also be romped on with quite a bit of amplifier power, and they don't mind being played loud. I've also had some people refer to them as 'bright', and I don't fully disagree, but while the on-axis response isn't the flattest of flat, the overall balance is pretty flat and there are no serious peaks; I attribute any brightness to some residual character of the Beston planar.
The mid crosses to the tweeter at 5kHz because the Beston (and small planars in general) don't like to play low with low distortion, so this keeps the tweeter from being stressed; I recall somebody measured that the distortion of the Beston tweeter started to rise below 4kHz. The mid, being a 'full range' driver, is perfectly happy playing up that high without odd breakup effects. There's a third-order filter on the tweeter and second-order on the upper end of the midrange bandpass, then a first-order cap on the low end of the midrange bandpass, which is somewhere around 150-200 Hz as I recall. Then on the side-firing woofer, there's a coil that puts a first-order corner somewhere around 200 Hz, with the extra wide overlap between the woofer and the midrange being intended to offset baffle-step in the midrange, and provide some side fill. To keep the side-firing woofer from playing up too high, there is also a second pole (so the filter transitions to 2nd order) up around 450 Hz formed by a parallel capacitor after the coil. I was more careful about the integration between the tweeter and midrange in the crossover design, but the unconventional woofer filter was about trying to solve issues in practical ways rather than adhere to any particular filter topology.
The mixed reviews have kept me from publishing much about the design. They are okay, I count them as a successful experiment, and for the money I am very pleased with them, but there are many better speakers out there that you should spend your money building.
I can't edit my post but one detail left out is that the cabinet is tuned somewhere between 40-45 Hz, I forget exactly where, but it's probably on the lower end of that to keep the alignment overdamped. When they are in a typical size room with a bit of rear wall loading, they play into the 40s reasonably well and have some thump, but also some high-Q character that may not be to everyone's liking.
Ken, thanks for the nice set of pictures. Looks like you all had a good time.
Rory, good to hear from you again. Thanks for the detailed description of the Iguanas. I always learn something new when reading your posts or talking to you at events. I like how you overlapped the woofer/mid xover to fill in somewhat for baffle step. Good idea.
@AcousticTheory said:
I can't edit my post but one detail left out is that the cabinet is tuned somewhere between 40-45 Hz, I forget exactly where, but it's probably on the lower end of that to keep the alignment overdamped. When they are in a typical size room with a bit of rear wall loading, they play into the 40s reasonably well and have some thump, but also some high-Q character that may not be to everyone's liking.
It would be interesting if you could go into more detail on the woofer crossover as I may need to do something similar.
Comments
Awesome to see the MAC drivers represented!
Thanks Ken!
Awesomeness!
Fine craftsmanship on display!
Speaking of radio shack, this is the sign above my museum:
I was chatting with another member about going to this next year, I'll try to make it happen.
Incredible looking speakers!
Great paint on the green towers, is there a post I've missed on this build?
I liked the dyed blue tower! More info?
In the case anyone wants to find the high voltage poly caps I brought to Detroit, here is a link or 2 for some of them:
https://www.ebay.com/sch/i.html?_nkw=electronic+concepts+eci+capacitors+mp+ul&_trksid=p2334524.m4084.l1313&_odkw=electronic+concepts+eci+capacitors+mp
https://www.ebay.com/sch/i.html?_nkw=electronic+concepts+capacitors+mp&_pgn=1
The UL600 Unlytics are stretched polypropylene film meant to fit in standard 3" diameter size. They come in the same case as the DC PSU types, and the ends are even marked polarized, but they are nonpolar.
The MP9 series are available in large voltage capacities, which means larger contact surfaces and lower ESR.
Ebay has some favorable prices at times, for example, there is a 10x pack of 10uF 600VDC for $60 plus $30 shipping.
Another is 6x 30uF 750VDC for the same price.
InDIYana Event Website
Those were Rory Buska's speakers, he said they were the last DIY build he completed, back in 2015. He mentioned the paint shop that did the work, but it wasn't something I am familiar with so I don't remember the name. But the picture isn't lying, the paint job was pretty impressive.
The Blue towers were I believe a pending or already released 3way CSS kit.
Steve Fishe in Tennessee painted the Iguanas when Rory (Buszka, btw) was at Thiel.
InDIYana Event Website
Rory, what can you tell us about your build? Assuming 3-ways (?), drivers, approx crossover frequencies / design, ported ? thx
The blue tower is the 3TD-X. Great speaker.
https://www.css-audio.com/online-store/CSS-Criton-3TD-X-Kit-Pair-p644003321
Rory I believe has shed all social media from his life. He still emails, but is not on FB or any forums any longer. This has been this way for a few years now.
I can tell you the drivers though. The Beston RT002 sealed back planar is the top-end. The midrange is the GRS Pioneer 4" replacement driver 4FR-8 in a sealed chamber. The the woofer is the GRS 8SW-4 Poly cone subwoofer in a vented box.
If you are really curious, I can see if he wants to pop in here and give more details...
InDIYana Event Website
Hi, this is Rory from the event.
Ben is right, I have shed social media from my life for my own reasons, apart from LinkedIn (which I visit infrequently but keep updated) but I also have not published very much on the Iguanas, because the reviews in different venues have been mixed. I have a pair of more technically perfect speakers in the house, which are Thiel CS1.7 towers, and of course I have the Neutrinos from 2012 which still make me very happy on my desk, but there are things the Iguanas do that make them probably the most 'fun' all-around speakers I have. They have elements of the 'three way sound' and also the lightning quick treble reflexes of a planar tweeter, along with good subjective speed and dynamics from the 4" mid, which is a GRS clone of an older Pioneer 4.5" full range speaker.
The bass section is maybe the weakest link in the speaker, although I think it's 'fine'; the GRS 8SW-4 is in a slightly under-sized (and thereby overdamped) bass reflex alignment to try to reduce peakiness due to the woofer's high Qts. It can also be romped on with quite a bit of amplifier power, and they don't mind being played loud. I've also had some people refer to them as 'bright', and I don't fully disagree, but while the on-axis response isn't the flattest of flat, the overall balance is pretty flat and there are no serious peaks; I attribute any brightness to some residual character of the Beston planar.
The mid crosses to the tweeter at 5kHz because the Beston (and small planars in general) don't like to play low with low distortion, so this keeps the tweeter from being stressed; I recall somebody measured that the distortion of the Beston tweeter started to rise below 4kHz. The mid, being a 'full range' driver, is perfectly happy playing up that high without odd breakup effects. There's a third-order filter on the tweeter and second-order on the upper end of the midrange bandpass, then a first-order cap on the low end of the midrange bandpass, which is somewhere around 150-200 Hz as I recall. Then on the side-firing woofer, there's a coil that puts a first-order corner somewhere around 200 Hz, with the extra wide overlap between the woofer and the midrange being intended to offset baffle-step in the midrange, and provide some side fill. To keep the side-firing woofer from playing up too high, there is also a second pole (so the filter transitions to 2nd order) up around 450 Hz formed by a parallel capacitor after the coil. I was more careful about the integration between the tweeter and midrange in the crossover design, but the unconventional woofer filter was about trying to solve issues in practical ways rather than adhere to any particular filter topology.
The mixed reviews have kept me from publishing much about the design. They are okay, I count them as a successful experiment, and for the money I am very pleased with them, but there are many better speakers out there that you should spend your money building.
I can't edit my post but one detail left out is that the cabinet is tuned somewhere between 40-45 Hz, I forget exactly where, but it's probably on the lower end of that to keep the alignment overdamped. When they are in a typical size room with a bit of rear wall loading, they play into the 40s reasonably well and have some thump, but also some high-Q character that may not be to everyone's liking.
Nice to see you here Rory.
Rory,
Thank you for the info - much appreciated
Thanks for chiming in, Bud!
InDIYana Event Website
Ken, thanks for the nice set of pictures. Looks like you all had a good time.
Rory, good to hear from you again. Thanks for the detailed description of the Iguanas. I always learn something new when reading your posts or talking to you at events. I like how you overlapped the woofer/mid xover to fill in somewhat for baffle step. Good idea.
Thanks for the pics, Ken. This is one venue I haven't attended but couldn't make it this year, so have to settle for pics.
Marv
You going to make it to Iowa Marvin?
It would be interesting if you could go into more detail on the woofer crossover as I may need to do something similar.