Next up in the test box is the B&C 12FG100. Impressive driver it has a 4" coil with a 2000W continuous program power capacity. Cone is thick with waterproofing on both sides.
Here's the max spl at 5% distortion measurements:
Frequency Spl of fundamental 2nd harmonic 3rd harmonic
16 68 -44 -25
20 68 -42 -25
25 70 -31 -24
31.5 67 -23 -32
40 85 -25 -41
50 108 -28 -25
63 110 -25 -38
Here's the max spl at 5% distortion measurements:
Frequency Spl of fundamental 2nd harmonic 3rd harmonic
16 68 -44 -25
20 68 -42 -25
25 70 -31 -24
31.5 67 -23 -32
40 85 -25 -41
50 108 -28 -25
63 110 -25 -38
Attachments
I then tried the B&C in the 85 liter 38hz vented alignment.
As most pro drivers it's t/s parameters are more for vented boxes.
Here's the max spl at 5% distortion measurements:
Frequency Spl of fundamental 2nd harmonic 3rd harmonic
16 58 -32 -19
20 66 -36 -24
25 85 -25 -26
31.5 86 -24 -41
40 93 -24 -33
50 110 -25 -27
63 112 -25 -36
attached is 60hz @80db and 100 db
As most pro drivers it's t/s parameters are more for vented boxes.
Here's the max spl at 5% distortion measurements:
Frequency Spl of fundamental 2nd harmonic 3rd harmonic
16 58 -32 -19
20 66 -36 -24
25 85 -25 -26
31.5 86 -24 -41
40 93 -24 -33
50 110 -25 -27
63 112 -25 -36
attached is 60hz @80db and 100 db
Attachments
Last up with the B&C is the 85 liter 17hz passive tune.
One thing I noticed is the upper harmonics like 4th and 5th are lower than most of the other drivers, this can be seen in the 60hz@100db graph. The only driver that's cleaner is the Audio Technology (with passive radiator) in the 4th and 5th harmonics at 60hz.
Here's the max spl at 5% distortion measurements:
Frequency Spl of fundamental 2nd harmonic 3rd harmonic
16 71 -25 -41
20 88 -37 -26
25 82 -33 -25
31.5 65 -18 -25
40 87 -25 -29
50 108 -26 -25
63 111 -26 -40
attached is 60hz @80db and 100 db
One thing I noticed is the upper harmonics like 4th and 5th are lower than most of the other drivers, this can be seen in the 60hz@100db graph. The only driver that's cleaner is the Audio Technology (with passive radiator) in the 4th and 5th harmonics at 60hz.
Here's the max spl at 5% distortion measurements:
Frequency Spl of fundamental 2nd harmonic 3rd harmonic
16 71 -25 -41
20 88 -37 -26
25 82 -33 -25
31.5 65 -18 -25
40 87 -25 -29
50 108 -26 -25
63 111 -26 -40
attached is 60hz @80db and 100 db
Attachments
Next up is the Dayton Audio RSS315HE-22 a new high excursion model variant of the reference series. This driver doesn't disappoint and can really blast out clean deep bass even in the 85 liter sealed alignment I tried it in first.
In case someone asks, I prefer the sound of the this driver over the Dayton Audio RSS315HFA-8 12" Reference HF. After accounting for voice coil resistance the HE sub has a higher motor strength to weight ratio than the HF so it could be that. But as I've been learning you can't just pick out one parameter that provides better sound quality it's all the parameters working together. Also from my testing the HE has lower higher order distortion like 4th, 5th etc than the HF. See post #3 for more info on the HF.
The HE also has the lowest 30 and 72hz IMD (1.26%) at 80db of the eight drivers in total I tested including drivers 2 or 3 times the price. See attached graph for the spectrogram and compare this with the graphs in post #192.
Here's the max spl at 5% distortion measurements:
Frequency Spl of fundamental 2nd harmonic 3rd harmonic
16 79 -41 -24
20 75 -25 -25
25 67 -24 -35
31.5 66 -24 -35
40 95 -25 -40
50 112 -25 -40
63 112 -28 -40
attached is 60hz @80db and 100 db
In case someone asks, I prefer the sound of the this driver over the Dayton Audio RSS315HFA-8 12" Reference HF. After accounting for voice coil resistance the HE sub has a higher motor strength to weight ratio than the HF so it could be that. But as I've been learning you can't just pick out one parameter that provides better sound quality it's all the parameters working together. Also from my testing the HE has lower higher order distortion like 4th, 5th etc than the HF. See post #3 for more info on the HF.
The HE also has the lowest 30 and 72hz IMD (1.26%) at 80db of the eight drivers in total I tested including drivers 2 or 3 times the price. See attached graph for the spectrogram and compare this with the graphs in post #192.
Here's the max spl at 5% distortion measurements:
Frequency Spl of fundamental 2nd harmonic 3rd harmonic
16 79 -41 -24
20 75 -25 -25
25 67 -24 -35
31.5 66 -24 -35
40 95 -25 -40
50 112 -25 -40
63 112 -28 -40
attached is 60hz @80db and 100 db
Attachments
For my purposes, I like the even FR between 20 & 40hz.
Per PE’s Bass box modeling the DA RSS315HE-22* doesn’t reach as low as the RSS315HFA-8 by about half an octave. OTOH taking the good w/the bad, PE’s BB modeling shows it* performs well in closures about 1/3 the size
Q: is your vented displacement ideal for this driver? Do ya think PE’s BB modeling is pretty accurate.
Thanks in advance for your efforts. Tony
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Hi Tony, Keep in mind the numbers I generate are how loud I can play it at each frequency before I hit approximately 5% distortion(-25 db down), they are not frequency response. Like for example at 20hz I can hit 88db and the 2nd harmonic distortion is -37db down (51db) and the 3rd harmonic distortion is -26 db (62db) down. Here's the link to the sub.
Dayton Audio RSS315HE-22 12" Reference Series High Excursion Subwoofer 2+2 ohm
Dayton Audio RSS315HE-22 12" Reference Series High Excursion Subwoofer 2+2 ohm
Next up for the HE reference is the 85 liter 38hz vented. With a Vas of 32.4 liters my 85 liter box is too big and the result is a peaky response, however I wanted to see how well the driver drives the port and there are no issues here. Especially strong output well below tuning at 25hz.
Here's the max spl at 5% distortion measurements:
Frequency Spl of fundamental 2nd harmonic 3rd harmonic
16 64 -44 -19
20 74 -37 -24
25 96 -25 -26
31.5 86 -26 35
40 90 -24 -32
50 112 -27 -36
63 112 -33 -41
attached is 60hz @80db and 100 db
Here's the max spl at 5% distortion measurements:
Frequency Spl of fundamental 2nd harmonic 3rd harmonic
16 64 -44 -19
20 74 -37 -24
25 96 -25 -26
31.5 86 -26 35
40 90 -24 -32
50 112 -27 -36
63 112 -33 -41
attached is 60hz @80db and 100 db
Attachments
Tony, I think you have found the tradeoff between the HFA-8 and the HE. One of the sources of distortion is Current so the more efficient a driver is the less distortion it will have. The HFA-8 is more efficient than the HE but needs a bigger box. I think this is why the HFA-8 is putting out more db at my 5% distortion test especially in the low bass.
Of the three different alignments, I actually prefer the HE in a sealed box as I get a real shallow roll off that works with the boost of low frequencies by the room.
To answer your question about modelling, I think bassbox and winisd do a good job but you have to remember drivers are non-linear and as they start to move the t/s parameters shift. A good driver will show less of this but it's still there, I've attached a graph of the .Qts of a AE TDH6 midbass, the .Qts is almost double by 7mm.
Of the three different alignments, I actually prefer the HE in a sealed box as I get a real shallow roll off that works with the boost of low frequencies by the room.
To answer your question about modelling, I think bassbox and winisd do a good job but you have to remember drivers are non-linear and as they start to move the t/s parameters shift. A good driver will show less of this but it's still there, I've attached a graph of the .Qts of a AE TDH6 midbass, the .Qts is almost double by 7mm.
Attachments
I just replied to your Facebook post. The peerless SDF250 seems to be the replacement for the xxls series. However the line seems to be totally under the radar, the 12in and 15in versions are monsters in spec but not really available.
The SDF250 is available at digikey at a nice price.
Blocked
Last test for the Dayton HE is the 85 liter passive 17hz tune. An interesting thing happened when testing this driver, I was playing a 20hz tone at around 85db and what could I hear? Absolutely nothing! I just felt pressure in the room. The driver is running so clean at 20hz and 85db that my ear couldn't pick up the harmonics or hear any mechanical noise.
Here's the max spl at 5% distortion measurements:
Frequency Spl of fundamental 2nd harmonic 3rd harmonic
16 74 -23 -40
20 89 -24 -27
25 80 -26 -36
31.5 60 -18 -21
40 95 -25 -45
50 110 -25 -50
63 112 -39 -48
attached is 60hz @80db and 100 db
Here's the max spl at 5% distortion measurements:
Frequency Spl of fundamental 2nd harmonic 3rd harmonic
16 74 -23 -40
20 89 -24 -27
25 80 -26 -36
31.5 60 -18 -21
40 95 -25 -45
50 110 -25 -50
63 112 -39 -48
attached is 60hz @80db and 100 db
Attachments
Next driver is the Morel TiCW 1258 ft. An easy route to good sound is to drop one of these into a sealed box. This driver is one of the best in all around music, jazz, classic rock, hiphop all sounded great. This driver did the best job of all the other subwoofers I've tried in reproducing one of my test tracks that contains a large Taiko drum. I've analyzed this song and it contains large simultaneous peaks at 60 and 105hz. I believe part of the reason the Morel did so well in this track is it's low inductance. A driver with high inductance playing 60hz might cause the 105hz component to be compressed.
This driver seems to have a different distortion profile then others when listening at moderate levels it sounds very clean but as it gets louder distortion sets in. This can be seen be in my measurements of IMD at 60 and 144hz. At 80 db it is nearly the best but at 90 db other drivers are cleaner.
Here's the max spl at 5% distortion measurements in the sealed box:
Frequency Spl of fundamental 2nd harmonic 3rd harmonic
16 65 -43 -24
20 70 -30 -24
25 60 -24 -25
31.5 57 -22 -29
40 88 -26 -32
50 108 -24 -23
63 110 -25 -35
attached is 60hz @80db and 100 db
This driver seems to have a different distortion profile then others when listening at moderate levels it sounds very clean but as it gets louder distortion sets in. This can be seen be in my measurements of IMD at 60 and 144hz. At 80 db it is nearly the best but at 90 db other drivers are cleaner.
Here's the max spl at 5% distortion measurements in the sealed box:
Frequency Spl of fundamental 2nd harmonic 3rd harmonic
16 65 -43 -24
20 70 -30 -24
25 60 -24 -25
31.5 57 -22 -29
40 88 -26 -32
50 108 -24 -23
63 110 -25 -35
attached is 60hz @80db and 100 db
Attachments
Last edited:
Next up is the Morel in the 85 liter 38hz vented alignment. This results in a peaky response but I still ran the test to see how the driver can load the port. The numbers show that the Morel has a stiff cone and strong motor that allows for quite a bit more spl at tuning than the sealed alignment.
Here's the max spl at 5% distortion measurements:
Frequency Spl of fundamental 2nd harmonic 3rd harmonic
16 53 -31 -20
20 71 -39 -25
25 82 -24 -29
31.5 87 -26 -33
40 97 -25 -28
50 110 -25 -28
63 112 -27 -37
attached is 60hz @80db and 100 db
Here's the max spl at 5% distortion measurements:
Frequency Spl of fundamental 2nd harmonic 3rd harmonic
16 53 -31 -20
20 71 -39 -25
25 82 -24 -29
31.5 87 -26 -33
40 97 -25 -28
50 110 -25 -28
63 112 -27 -37
attached is 60hz @80db and 100 db
Attachments
Last test for the Morel is the 85 liter 17hz passive radiator alignment. As can be expected with it's 5.1" voice coil dynamics are really good with the Morel. In another track with large drums "Poem of a Chinese drum" the attack and decay of the drum sounded just right and I could feel the pressure of the drum hits in my chest.
Couldn't get a good 31.5hz reading as the 2nd harmonic was really high but I believe this to be partly due to path length interference with the active and passive driver as I've had this issue with the other drivers.
Here's the max spl at 5% distortion measurements:
Frequency Spl of fundamental 2nd harmonic 3rd harmonic
16 67 -23 -35
20 86 -33 -25
25 79 -24 -27
31.5
40 87 -25 -30
50 109 -25 -23
63 110 -25 -35
attached is 60hz @80db and 100 db
Couldn't get a good 31.5hz reading as the 2nd harmonic was really high but I believe this to be partly due to path length interference with the active and passive driver as I've had this issue with the other drivers.
Here's the max spl at 5% distortion measurements:
Frequency Spl of fundamental 2nd harmonic 3rd harmonic
16 67 -23 -35
20 86 -33 -25
25 79 -24 -27
31.5
40 87 -25 -30
50 109 -25 -23
63 110 -25 -35
attached is 60hz @80db and 100 db
Attachments
Looking for a DIY subwoofer
I recently finished building a pair of Pi Speakers 7pi (Building the 7pi (seven pi) speakers - Spring/Summer 2021) and they sound great, but need a subwoofer. I found this thread while looking for a DIY subwoofer project which can complement the 7pi speakers. I listen at moderate levels and drive a 25W/channel amplifier directly from the DAC. I am thinking of a single box with a plate amplifier. From what I have read so far it seems as if the SB SB34NRXL75-8 and the Dayton Audio RSS315HE-22 are good choices. I would like to hear comments and suggestions from those experienced in designing and building subwoofer boxes.
I recently finished building a pair of Pi Speakers 7pi (Building the 7pi (seven pi) speakers - Spring/Summer 2021) and they sound great, but need a subwoofer. I found this thread while looking for a DIY subwoofer project which can complement the 7pi speakers. I listen at moderate levels and drive a 25W/channel amplifier directly from the DAC. I am thinking of a single box with a plate amplifier. From what I have read so far it seems as if the SB SB34NRXL75-8 and the Dayton Audio RSS315HE-22 are good choices. I would like to hear comments and suggestions from those experienced in designing and building subwoofer boxes.
grimberg- your speakers look great, nice job!
Those are both excellent woofers and both work pretty well in relatively small vented enclosures of 2-2.5 cu ft. The Dayton will play lower and the SB will have higher sensitivity but not play quite as low.
Do you plan to high-pass the 7pi?
Does you dac have additional outputs, rca or xlr?
Do you plan to use dsp?
I would encourage you to go for more than 1 subwoofer. At least 2 but I prefer 4 myself.
Those are both excellent woofers and both work pretty well in relatively small vented enclosures of 2-2.5 cu ft. The Dayton will play lower and the SB will have higher sensitivity but not play quite as low.
Do you plan to high-pass the 7pi?
Does you dac have additional outputs, rca or xlr?
Do you plan to use dsp?
I would encourage you to go for more than 1 subwoofer. At least 2 but I prefer 4 myself.