Good point about the 12dB shelving - probably means Max SPL is limited. But as you say, phase plug may make all the difference.
Thanks for looking.
Thanks for looking.
Shelving is a nice invention but limit the driver dramatically, just look at a open baffle or a sub H-frame, because of canceling back and front cone.
But you now afcourse.
regards
But you now afcourse.
regards
10F version
Hi,
About the Scanpeak 10F/84 version (2" throat) :
If I suceed to putt two 10" per horn instead 4 x 6.5": here is a good input with the Beyma 10G40 http://www.diyaudio.com/forums/mult...section-design-beyma-10g40-4.html#post4534357 : good inputs around a sealed 10"
Total Sd of 2*10" is close to 4*6.5".
VASof this Beyma match the 10 L for a Qts between 0.7 & 0.5
Max SPL > 116 dB around 100 Hz (and even lower with the smallest 6.5 L box) for 150W.
We stay with sealed design
Hi,
About the Scanpeak 10F/84 version (2" throat) :
If I suceed to putt two 10" per horn instead 4 x 6.5": here is a good input with the Beyma 10G40 http://www.diyaudio.com/forums/mult...section-design-beyma-10g40-4.html#post4534357 : good inputs around a sealed 10"
Total Sd of 2*10" is close to 4*6.5".
VASof this Beyma match the 10 L for a Qts between 0.7 & 0.5
Max SPL > 116 dB around 100 Hz (and even lower with the smallest 6.5 L box) for 150W.
We stay with sealed design
Did you look at Tang Band W2-748SG 2" Full Range Driver.
8 ohm
10 watt
Fs 160Hz
0.75 mm xmax
Qes 0.26
Qts 0.28
I was looking at it for a possible 3 way synergy midrange. Might be a bit pricey at $26 each in 4's.
Marc
8 ohm
10 watt
Fs 160Hz
0.75 mm xmax
Qes 0.26
Qts 0.28
I was looking at it for a possible 3 way synergy midrange. Might be a bit pricey at $26 each in 4's.
Marc
Thanks for the tip. The simple concave diaphragm may work well for a comp driver like phase plug.
At only .75 mm Xmax with a 2" cone, about 12 dB less output potential than the 10F.
And once you venture into a high compression HF phase plug, the low BL won't allow it to produce much HF output, and will increase distortion.
Here:
Beyma 10G40 : 120 euros
B&C 10CL51 : 90 euros (beginn to be hard to source : discontinued)
Same Vas ! I don't know if the two brands are measuring on a IE bafle ?
The B&C is rolling off rapidly around 150 Hz and has a Qts of 0.4
The Beyma seems to have a lower roll off and has a Qts of 0.31
The B&C seems easier for a sealed though both were designed for a vented ! And despite the rapid roll off at 150 Hz has a higher average spl : 95 dB !
The main problem is I don't find the B&C in a brick&mortar shop ! Hummm I have to call maybe the shop who sold me the 10F, I believe they can find it !
According to the data sheet, that looks quite good, but how do you mount something like that? Glue (not friendly for making port adjustments)? Some kind of clamp over the back or over the back sealing cup?
A bracket with a round cutout to go around the rear basket and with 4 holes to clamp the bezel to the horn wall would be required. Simple but a pain to make. Could be 3D printed easily enough. Aluminum sheet metal with a round hole punch can work too.
That does not look quite sturdy enough to clamp the main driver on without slipping off due to vibration. I will be going with the W2-852SH anyway as I have them on hand, although they only measure to be Qts=0.49 - so it may appear Tang Band was a little optimistic in their driver's magnet strength.
Actually, the Qts rarely measures as low as a manufacturer states. They must always find the +3 standard deviation outlier to report...
This is usually only a problem with drivers that claim to be lower Qts. On the TC9FD, it measures 0.89, exactly spot on with spec.
Actually, the Qts rarely measures as low as a manufacturer states. They must always find the +3 standard deviation outlier to report...
This is usually only a problem with drivers that claim to be lower Qts. On the TC9FD, it measures 0.89, exactly spot on with spec.
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What a pity the chipboard makes the ports difficult to drill clean... it seems to have a very good damping behavior for top&bottom walls.... Certainly a material more in pair with foam than any plywood...
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micro Trynergy with W2-852SH
Here is a micro Trynergy made by scaling pdf plans by 0.48x. Horn mouth is 12.75in wide x 8.5in high x 11in deep - pretty compact. It does not use much foam core at all. I double layered it with CLD of liquid nails and another layer of foam core on curved walls and triple ply cardboard on flat walls.
Here is the build so far without woofers:
Driver mount detail:
For measurement, I set it up oriented with the curved walls along the vertical to see if it could work in a fairly compact format, and also to elevate the mouth high above the floor to reduce floor bounce:
It measures surprisingly well, with a sensitivity that is higher than I expected at 109dB at 2.83v and 1m (this is a 4ohm speaker). Also, the low frequencies extend much lower than I thought it would. Seems to be perfectly usable down to circa 350Hz, and without EQ, up to say 5kHz.
Here is distortion at 2.83v (full range direct drive, no hp capacitor) - I was basically mic limited as it maxes out at 115dB. This driver definitely has more distortion than SS 10F as the cone has to move more (smaller Sd):
Here is -3dB down from 2.83v (2.00v):
Here is -6dB down from 2.83v (1.41v):
Here is -10dB down from 2.83v (<0.7v):
Here is phase for -10dB case - looks like phase tracks well up to first cancellation at 9.1kHz which corresponds to the throat half-width:
Here are polars at 1m (5ms gate) for the orientation shown with curved horn walls along top and bottom:
Here is a micro Trynergy made by scaling pdf plans by 0.48x. Horn mouth is 12.75in wide x 8.5in high x 11in deep - pretty compact. It does not use much foam core at all. I double layered it with CLD of liquid nails and another layer of foam core on curved walls and triple ply cardboard on flat walls.
Here is the build so far without woofers:
Driver mount detail:
For measurement, I set it up oriented with the curved walls along the vertical to see if it could work in a fairly compact format, and also to elevate the mouth high above the floor to reduce floor bounce:
It measures surprisingly well, with a sensitivity that is higher than I expected at 109dB at 2.83v and 1m (this is a 4ohm speaker). Also, the low frequencies extend much lower than I thought it would. Seems to be perfectly usable down to circa 350Hz, and without EQ, up to say 5kHz.
Here is distortion at 2.83v (full range direct drive, no hp capacitor) - I was basically mic limited as it maxes out at 115dB. This driver definitely has more distortion than SS 10F as the cone has to move more (smaller Sd):
Here is -3dB down from 2.83v (2.00v):
Here is -6dB down from 2.83v (1.41v):
Here is -10dB down from 2.83v (<0.7v):
Here is phase for -10dB case - looks like phase tracks well up to first cancellation at 9.1kHz which corresponds to the throat half-width:
Here are polars at 1m (5ms gate) for the orientation shown with curved horn walls along top and bottom:
Attachments
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Sound quality is as expected from a high efficiency tractrix, superb. Without the bass assist it's hard to tell for the octaves below 300Hz, but the mid range on this without EQ is very good. To give a comparison, look for another mid range driver that has bandwidth from 350Hz to 5kHz with sensitivty this high. There is none. At 114dB, the measured distortion is higher than I would like to see - but when padded down to reasonable levels like 98dB (still loud) it sounds superb. Probably the best mid range driver would be the ATC SM75 3in soft dome - if one had to compare this with something. That driver has about 96dB sensitivity and is smooth from 400Hz to 4kHz. That driver also has a 15lb magnet and costs $800. To be fair, I have not heard an ATC SM75 - but based on sensitivity, distortion, bandwidth - I have to imagine what I am hearing might be similar, but even louder. I used some female vocals that lie in this mid range sweet spot that I know well to listen raw with no EQ. Ann Bisson sounded fantastic and I have very high hopes that once bass from four woofers are injected in, and a little EQ is used to bring out the top octaves - this will be quite the formidable compact speaker. I would have put in the bass ports etc but had to leave for travel just as I finished the base tractrix and mid/tweet.
I think the Faital Pro 3FE22 and SS 10F are both great sounding drivers as well, I have not heard the W2-852 long enough and with bass assist to give a comparison. What I have heard though sounds very good and most surprising is how loud it is and how low it goes for such a small horn.
I think the Faital Pro 3FE22 and SS 10F are both great sounding drivers as well, I have not heard the W2-852 long enough and with bass assist to give a comparison. What I have heard though sounds very good and most surprising is how loud it is and how low it goes for such a small horn.
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