Unless Greg's measurements show that my measurements are completely off, I will let my units in a corner and finish some other projects first. I do that because I agree with Norgaard's previous comment:
Indeed, for the price I find the consistency quite good (as mentioned earlier, the European distributor of B&G had to select them before reselling, and B&G DOA units were not uncommon), but further perfomance is neither horrific or great. As commented by Charlie, the HF is lacking and well, could maybe be improved with EQ, but needs testing and more off-axis measurements (look at Darkheart's post below).
Currently, my only interest in these is for a dipole line array, much as done by mlee 3-Way Open Baffle Straight Line Array (Floor to Ceiling) and Darkheart https://www.diyaudio.com/forums/multi-way/337631-radian-audio-lm8k-2.html#post6366395 So I am not planning to measure them in baffles or enclosures. Unfortunately, the cost for the line arrays is not only these, but all the woofers, that would have to play up to about 700-800Hz. So would become a three-way... overcomplicated for now
best regards,
Erik
Yes, that looks like rather big membrane tension differences
But considering the price one could have feared bigger individual deviations than this. Depending on the actual input level, distortion is not horrific nor great.
For the projects I have going on, the two peaks and relatively early drop off, as well as the tension and general slope makes it suboptimal.
Which does not mean that it's not a useful or manageable design in general
Thanks a lot Erik!
Indeed, for the price I find the consistency quite good (as mentioned earlier, the European distributor of B&G had to select them before reselling, and B&G DOA units were not uncommon), but further perfomance is neither horrific or great. As commented by Charlie, the HF is lacking and well, could maybe be improved with EQ, but needs testing and more off-axis measurements (look at Darkheart's post below).
Currently, my only interest in these is for a dipole line array, much as done by mlee 3-Way Open Baffle Straight Line Array (Floor to Ceiling) and Darkheart https://www.diyaudio.com/forums/multi-way/337631-radian-audio-lm8k-2.html#post6366395 So I am not planning to measure them in baffles or enclosures. Unfortunately, the cost for the line arrays is not only these, but all the woofers, that would have to play up to about 700-800Hz. So would become a three-way... overcomplicated for now
best regards,
Erik
I have posted on-axis frequency response and distortion measurements of the GRS PT5010 and PT2522 as part of another thread that can be found HERE.
Now it is my turn to add my measurements:
I've only tried one of the two drivers I bought:
I've mounted it in a 30cm wide foamcore baffle with an 8mm sheet of fluffy wool carpet on the front. This is to add efficiency without a sharp dipole peak.
First up is just a rough 0-90 measurement. Pretty nice overall. It might be that covering the 2 outer rows is uneccesary since the driver is so slim which I might test in the future.
Next is distortion tests: The first two are without EQ except a LR4 highpass @ 600 hz. I estimated the impedance to be 6.5 ohm so 1W => 2.5V, 2W => 3.6V.
The next two are with lots of EQ such that the response fits a LR4 highpass @ 500 hz.
All of the distortion tests are measured at 0.5m with SPL - 6 dB => calibrated for 1m.
As my plan would be to get 7 of them in a shaded array, on the low end I'll get the performance of ~ 4 of them so. On the low end I estimate about 4 drivers will sum nicely so I'll get around 12 dB higher output SPL given the same performance due to more drivers.
Since it starts to distort more above 91 dB that would let it play cleanly up to 103 dB which is way more than I need. And semi-clean at 106 dB where it hits 1% THD @ 550 hz.
For my case, crossing a line of them at 500 hz LR4 shouldn't be a problem at all. If anything I could possibly cross them even lower. But I'll probably stay on the conservative side and stay at 500 hz so I don't push my midwoofers too high.
I've only tried one of the two drivers I bought:
I've mounted it in a 30cm wide foamcore baffle with an 8mm sheet of fluffy wool carpet on the front. This is to add efficiency without a sharp dipole peak.
First up is just a rough 0-90 measurement. Pretty nice overall. It might be that covering the 2 outer rows is uneccesary since the driver is so slim which I might test in the future.
Next is distortion tests: The first two are without EQ except a LR4 highpass @ 600 hz. I estimated the impedance to be 6.5 ohm so 1W => 2.5V, 2W => 3.6V.
The next two are with lots of EQ such that the response fits a LR4 highpass @ 500 hz.
All of the distortion tests are measured at 0.5m with SPL - 6 dB => calibrated for 1m.
As my plan would be to get 7 of them in a shaded array, on the low end I'll get the performance of ~ 4 of them so. On the low end I estimate about 4 drivers will sum nicely so I'll get around 12 dB higher output SPL given the same performance due to more drivers.
Since it starts to distort more above 91 dB that would let it play cleanly up to 103 dB which is way more than I need. And semi-clean at 106 dB where it hits 1% THD @ 550 hz.
For my case, crossing a line of them at 500 hz LR4 shouldn't be a problem at all. If anything I could possibly cross them even lower. But I'll probably stay on the conservative side and stay at 500 hz so I don't push my midwoofers too high.
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Thanks for the measurements gentlemen. I'd really like to see measurements comparing the Neo10 and PT5020-8 whether they are nude or on a baffle.
I really want to try the Neo10 with Neo3 but the cost of Neo10 have gotten ridiculous. My current system uses the Neo8 and Neo3 with an 8" woofer, which I love.
The new GRS drivers are very competitively priced so taking a chance is worth it. I just dont have a Neo10 to do measurements on for comparison.
I really want to try the Neo10 with Neo3 but the cost of Neo10 have gotten ridiculous. My current system uses the Neo8 and Neo3 with an 8" woofer, which I love.
The new GRS drivers are very competitively priced so taking a chance is worth it. I just dont have a Neo10 to do measurements on for comparison.
I'd go further and say they are pretty good AND cheap
And from what I've seen in previous measurements in the thread consistency seems to be acceptable too.In my case as long as I can validate my mini-woofer setup* which I hope to do tomorrow then I'll probably order 14x more of the Slim 8" drivers. And considering that they perform well enough to be crossed at 500 hz I'd be very suprised if woofer integration became a problem.
*The current idea is to use my 2.5" SB65WBAC25 in slots along each side of the Slim 8"s where in the space between the drivers to not block the signal. In the second image of post #85 New planar drivers at Parts Express you can see the red markings for where the slots will be.
These are nice measurements OllBoll, from the equalized curves it looks as if you are planning to let them play HF (no additional tweeter)?
I am still thinking what to do... I think these would make for some very cost effective dipole floor to ceiling array, which I have been wanting to try since I saw StigErik with his 2 way based on RD75 and 21" woofers. RD75 is not being sold anymore, the other B&G stuff became so expensive and they do not have a unit as the 8" slim (that can be used up to 20khz and same some low end as well, the NEO3 does not...).
I do not want to stockpile stuff for another next project, but OTOH afraid that the prices for this unit may increase. I think I will manage to have a listen to a unit tomorrow, maybe that will make decisions easier
Still, very nice to see more measurements that confirm that these units are quite ok. Still looking forward to Studiotech's measurements!
I am still thinking what to do... I think these would make for some very cost effective dipole floor to ceiling array, which I have been wanting to try since I saw StigErik with his 2 way based on RD75 and 21" woofers. RD75 is not being sold anymore, the other B&G stuff became so expensive and they do not have a unit as the 8" slim (that can be used up to 20khz and same some low end as well, the NEO3 does not...).
I do not want to stockpile stuff for another next project, but OTOH afraid that the prices for this unit may increase. I think I will manage to have a listen to a unit tomorrow, maybe that will make decisions easier
Still, very nice to see more measurements that confirm that these units are quite ok. Still looking forward to Studiotech's measurements!
Yes, that is exactly what I am planning. I think the Slim 8" would be an awkward driver to not run as a tweeter. If you are crossing to a tweeter then why not just get multiples of the wide 8" so you can cross lower or the bigger 10" so you can cross even lower? And it certainly has good enough dispersion at 10-20 khz so I don't believe a dedicated tweeter is neccesary. It's basically just a very tall Neo3 which is a pretty good tweeter on it's own.
But in my case I've been bitten by the full range bug so I want to avoid a crossover in the 1 khz + range. Every time I've tried (except in a coaxial setup) I have created more problems than I solved, and it got ugly really fast when I started measuring off-axis reponse above and below ear level. With an array of Slim 8" I can cross far below where such issues start to appear which is nice.
I did test my mini-woofer setup and it worked great. The response was great up to 1.2 khz so crossing at 500 hz should be no problem at all. My idea is to basically build a dipole coaxial setup
. This of course would be duplicated and stacked on top of each other in the CBT array.The only reason I haven't yet ordered 14 more of the Slim 8"s is that I have a $25 off any purchase of $250 or more coupon code @ Parts Express that is valid from next sunday
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Sorry I disappeared y'all. It's been super busy at the day job and the side gigs.
Here's a test upload of the NEO10/GRS10 comparison. I want to see if my snapshot looks clear and large enough and then I'll upload some more.
Neo10, sample #1 was set to 95dBSPL at 1ft and all gain settings were left untouched for the rest of the measurements. I've smoothed these snapshots to 12dB/oct.
Greg
Here's a test upload of the NEO10/GRS10 comparison. I want to see if my snapshot looks clear and large enough and then I'll upload some more.
Neo10, sample #1 was set to 95dBSPL at 1ft and all gain settings were left untouched for the rest of the measurements. I've smoothed these snapshots to 12dB/oct.
Greg
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Distortion plots. 2nd order is RED and 3rd order is ORG
The original BG NEO8-PDRs kill it as long as you stay above 600-700Hz. Both samples were almost identical. Midrange performance from a simple harmonic distortion perspective is fantastic.
Most disappointed in the Radian, but it's still totally acceptable if you consider most of it's range is still below -40dB down or under 1%. Even some of the other drivers that look like they have a bad spike in the upper midrange are still at least -40dB, so overall pretty usable.
The Slim 8 is the worse of the bunch, as expected, with the highest levels below 1KHz. But used as a line array of tweeters, they sure are a steal.
Greg
The original BG NEO8-PDRs kill it as long as you stay above 600-700Hz. Both samples were almost identical. Midrange performance from a simple harmonic distortion perspective is fantastic.
Most disappointed in the Radian, but it's still totally acceptable if you consider most of it's range is still below -40dB down or under 1%. Even some of the other drivers that look like they have a bad spike in the upper midrange are still at least -40dB, so overall pretty usable.
The Slim 8 is the worse of the bunch, as expected, with the highest levels below 1KHz. But used as a line array of tweeters, they sure are a steal.
Greg
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Has anyone measured the little 3.5" tweeter?
Dayton Audio PTMini-6 Planar Tweeter 6 Ohm
Sensitivity doesn't look great, no idea about distortion. But I'm wondering how a couple of these would do with 8" planar slim on either side?
Dayton Audio PTMini-6 Planar Tweeter 6 Ohm
Sensitivity doesn't look great, no idea about distortion. But I'm wondering how a couple of these would do with 8" planar slim on either side?
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