Anyone play with these lately ?
Not the fr8c (hemp acoustics).
The Hemptone fr8.
Hemptone Store
pdf doesn't work.
I've seen specs such as Qts=.45, Fs=40hz, and VAS=3.1ft3
Copper shorting ring is nice.
Not cheap at $128+$20 S/H.
Norman
Not the fr8c (hemp acoustics).
The Hemptone fr8.
Hemptone Store
pdf doesn't work.
I've seen specs such as Qts=.45, Fs=40hz, and VAS=3.1ft3
Copper shorting ring is nice.
Not cheap at $128+$20 S/H.
Norman
I'm thinking that the JAF Bombard used the slightly lighter (they mention 8gr cone).
6moons audio reviews: J.A.F. Bombard
"I can truly confirm how these are incredibly fast loudspeakers. They seem to reproduce the attack impulses far quicker than most. Even Avantgarde Acoustics hornspeakers which are already exceptional in this regard seem to lag behind just a bit as though they needed more time to think. Their presentation is almost the same as the JAF - faster than classic constructions but slightly slower than the Krakow speakers. " (I'd expect that from a time aligned setup with single cap on a ribbon).
"The crossover is a first-order filter but I couldn’t divine the exact parts because I couldn’t get at them. Looking through the rear gap we only see that the bass coil is wound on a toroidal core (probably from Jantzen) and covered with damping material. The high-frequency section uses a Jantzen polypropylene capacitor."
After reading the review, I'm still perplexed (perhaps unbelieving what the reviewer writes).
"His drivers can be used with a simple first-order filter to which the Bombard adds a baffle step filter............. They use four paralleled widebanders across the bass and midrange. For the treble there is a denuded RT2Pro Swans ribbon without the front."
I would have thought that it was a big mtm with 2 bottom drivers used as baffle step.
I'd assume that the top 8" is at ear height, and the 2 drivers closer to the floor won't cancel much (combing).
Then again I liked my first setup of a 4 vertical array of 8" (with whizzers), but I'm not sure if I'd like them now.
It may be interesting to try one of the Fr8 with the swans rt2h (single cap), then later add 2 more drivers for +6db baffle step.
Norman
6moons audio reviews: J.A.F. Bombard
"I can truly confirm how these are incredibly fast loudspeakers. They seem to reproduce the attack impulses far quicker than most. Even Avantgarde Acoustics hornspeakers which are already exceptional in this regard seem to lag behind just a bit as though they needed more time to think. Their presentation is almost the same as the JAF - faster than classic constructions but slightly slower than the Krakow speakers. " (I'd expect that from a time aligned setup with single cap on a ribbon).
"The crossover is a first-order filter but I couldn’t divine the exact parts because I couldn’t get at them. Looking through the rear gap we only see that the bass coil is wound on a toroidal core (probably from Jantzen) and covered with damping material. The high-frequency section uses a Jantzen polypropylene capacitor."
After reading the review, I'm still perplexed (perhaps unbelieving what the reviewer writes).
"His drivers can be used with a simple first-order filter to which the Bombard adds a baffle step filter............. They use four paralleled widebanders across the bass and midrange. For the treble there is a denuded RT2Pro Swans ribbon without the front."
I would have thought that it was a big mtm with 2 bottom drivers used as baffle step.
I'd assume that the top 8" is at ear height, and the 2 drivers closer to the floor won't cancel much (combing).
Then again I liked my first setup of a 4 vertical array of 8" (with whizzers), but I'm not sure if I'd like them now.
It may be interesting to try one of the Fr8 with the swans rt2h (single cap), then later add 2 more drivers for +6db baffle step.
Norman
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I have the FR8 and they seem to do well in a smaller enclosure. I tried them in a larger box and the impulse response suffered which muddied up male vocals.
They lack ultimate extension and therefore detail. They have great bass in the larger enclosure, but I'd still implement them in a FAST setup, especially a sealed mid chamber. The FR8 sounds very similar to the vintage Philips AN7060/M8. It's a nice sound. Not as good as markaudio alpair7.3eN, but better than Fostex FF165WK. It mates up well to paper cone tweeters.
They lack ultimate extension and therefore detail. They have great bass in the larger enclosure, but I'd still implement them in a FAST setup, especially a sealed mid chamber. The FR8 sounds very similar to the vintage Philips AN7060/M8. It's a nice sound. Not as good as markaudio alpair7.3eN, but better than Fostex FF165WK. It mates up well to paper cone tweeters.
it sounds nice in the video-- particularly the guitar - what is that paper cone tweeter? - physically it reminds me of the Quam tweeters I had 50 years ago but sounds better. Ah - its a Radio Shack unit and from the box picture, resembles the old CTS "phenolic ring" tweeter http://croweaudio.blogspot.ca/2014/01/realistic-cone-tweeter-40-1270d.html
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he's right on the brain "relaxing", without huge phase changes that happen with 12,18, and 24db (to my ears anyway).
Where's that video ?
Norman
Where's that video ?
Norman
here's his video - Joseph Crowe's DIY Speaker Building Blog: Hemp Acoustics FR8.1 video
and its YouTube address https://www.youtube.com/watch?v=C4MZKWp6uxo
and its YouTube address https://www.youtube.com/watch?v=C4MZKWp6uxo
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using laptop (no headphones), I'm sure it could use a squeek of baffle step.
But certainly a good start, yea, no honky-ness of a b20 whizzer !!!
His comment on a bit of greyness, probably a bit of ringing (you'd see it on a waterfall plot) from 1.5 - 4khz.
I wonder if removing the dustcap would lessen that spike at 8khz (s's and t's, bad spot for a resonance).
Not sure if I'm brave enough given the cost of the drivers.
And as I'd expect, a whizzered 8" has pretty good dispersion up to 4khz.
I havn't found too much on the forums about this driver.
Much on the hemp, but I'm not sure of they are referring to the 8gr cone version, or even the non-hemp version that came later just before the company (not hemptone) went belly up.
Norman
But certainly a good start, yea, no honky-ness of a b20 whizzer !!!
His comment on a bit of greyness, probably a bit of ringing (you'd see it on a waterfall plot) from 1.5 - 4khz.
I wonder if removing the dustcap would lessen that spike at 8khz (s's and t's, bad spot for a resonance).
Not sure if I'm brave enough given the cost of the drivers.
And as I'd expect, a whizzered 8" has pretty good dispersion up to 4khz.
I havn't found too much on the forums about this driver.
Much on the hemp, but I'm not sure of they are referring to the 8gr cone version, or even the non-hemp version that came later just before the company (not hemptone) went belly up.
Norman
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my BetsyK seems to have a higher ~10KHz peak than Joseph Crowe's FR8 measurements. On the cheap and with a suitable helper tweeter, I'd be tempted to try a Visaton BG20 with whizzer removed - finding the right tweeter would be the thing.
Does Betsy have a similar strength 10K peak - ?
Does Betsy have a similar strength 10K peak - ?
An externally hosted image should be here but it was not working when we last tested it.
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