Hello
This will be the first set of speakers I have built
2 Closed Boxed Cabinets - Using 1" Baltic Birch
Accuton Drivers
C30-6-358 Tweeter
C168-6-990 Mid
AS250-8-552 Bass
DSP 192-4-111
I have modelled the cabinets with BassBox. I am looking for any advice from experience builders to make sure my selection of drivers are a good match for each other and the cabinet size for the mid will work.
Bass Cabinet
Shape: Prism, slanted front
Vb = 45.64 liters
Qtc = 0.563
QL = 7
F3 = 53.04 Hz
Mid Range Cabinet
Vb = 2.672 liters
Qtc = 0.441
QL = 7
F3 = 236 Hz
I am pretty sure size for the Bass cabinet is ok for size but not too sure the Mid because of the QTC. Some of the post I read makes me think I do not need to worry about the QTC for Mid cabinet.
I am in the process of building the DSP in a cabinet now. I plan to use 1-rst order of 3500 for HP filter and 300 for LP filter.
This something I plan to take my time doing over the next 2 years and these speakers are to replace my apogee scintillas which I really liked the sound but I am now needing to replace the bass panel so I want to make sure these speakers are designed properly and make me as happy as the apogees.
This will be the first set of speakers I have built
2 Closed Boxed Cabinets - Using 1" Baltic Birch
Accuton Drivers
C30-6-358 Tweeter
C168-6-990 Mid
AS250-8-552 Bass
DSP 192-4-111
I have modelled the cabinets with BassBox. I am looking for any advice from experience builders to make sure my selection of drivers are a good match for each other and the cabinet size for the mid will work.
Bass Cabinet
Shape: Prism, slanted front
Vb = 45.64 liters
Qtc = 0.563
QL = 7
F3 = 53.04 Hz
Mid Range Cabinet
Vb = 2.672 liters
Qtc = 0.441
QL = 7
F3 = 236 Hz
I am pretty sure size for the Bass cabinet is ok for size but not too sure the Mid because of the QTC. Some of the post I read makes me think I do not need to worry about the QTC for Mid cabinet.
I am in the process of building the DSP in a cabinet now. I plan to use 1-rst order of 3500 for HP filter and 300 for LP filter.
This something I plan to take my time doing over the next 2 years and these speakers are to replace my apogee scintillas which I really liked the sound but I am now needing to replace the bass panel so I want to make sure these speakers are designed properly and make me as happy as the apogees.
I would strongly advise to get a different bass driver because of THIS. Pure Ceramic membranes are insanely stiff (theoretically ideal) but also extremely brittle. Too high excursion, be it because of no subsonic filter, power-on or power-off pop noise, unexpected peak, High Frequency interference (cell phone anyone?) or whatever, and your membrane shatters and the dirver is GONE! No, don't use a pure ceramic driver, there are tons of aluminium cone etc drivers available that do not shatter and got extensive frequency coverage and are so much cheaper, do not go for the pure ceramic drivers!
The bass according to their site is an aluminum sandwich and not ceramic. I don’t see me dropping the ceramic mid or tweeter out of my selection. I did consider
Flexunits 10 C 77 25 10 KAP by Audiotechnology as it appears to get some good reviews and it will save a bit of money. Most of the threads I have read only question whether the bass from Accuton is worth the money. Unless I get convinced that Accuton bass will not perform well I will probably stick with it.
Flexunits 10 C 77 25 10 KAP by Audiotechnology as it appears to get some good reviews and it will save a bit of money. Most of the threads I have read only question whether the bass from Accuton is worth the money. Unless I get convinced that Accuton bass will not perform well I will probably stick with it.
According to Accuton site the bass driver is aluminum sandwich. I do not plan to drop the ceramic mid or tweeter from my design. I did consider
Flexunits 10 C 77 25 10 KAP by Audiotechnology for the bass but the only negative I could find about the Accuton bass I picked was whether it was worth the money. I considered also whether it would be worth but in the end I decided to stick with it. If someone can convince me not to use it because of performance I may reconsider
Flexunits 10 C 77 25 10 KAP by Audiotechnology for the bass but the only negative I could find about the Accuton bass I picked was whether it was worth the money. I considered also whether it would be worth but in the end I decided to stick with it. If someone can convince me not to use it because of performance I may reconsider
Don't make a small (2-4 liter) closed cabinet for the mid,
you need to absorb the backwaves or let them escape, especially with the open back Accuton C168-6-990.
For my C173-6-090 I made a large lossy aperiodic cabinet (cone shaped) that let the backwave absorb and escape, see this post and this about Twaron.
See also the venturi vent in the Avalon clone with Accuton CELL.
My cone shaped mid cabinet resembles to this venturi.
Another nice larger mid cabinet in the XTZ divine.
I estimate about 10 liters in the XTZ.
Regards,
Danny
you need to absorb the backwaves or let them escape, especially with the open back Accuton C168-6-990.
For my C173-6-090 I made a large lossy aperiodic cabinet (cone shaped) that let the backwave absorb and escape, see this post and this about Twaron.
See also the venturi vent in the Avalon clone with Accuton CELL.
My cone shaped mid cabinet resembles to this venturi.
Another nice larger mid cabinet in the XTZ divine.
I estimate about 10 liters in the XTZ.
Regards,
Danny
Last edited:
I was concerned that my mid cabinet was too small and wanted to enlarge it but I was concerned about the qtc. Based on what you are saying I am assuming QTC is more of a concer for a bass cabinet. Your mid was a bit larger but do you think if I design my cabinet to be approx 10 lit it would not be too large.
I think that your primary concern should be minimizing the impact of the mid backwave.
See also the mid cabinets at Troels site, they're all larger.
Best is to make a test cabinet for the mid only with a moveable backside so you can adjust the volume.
This test cabinet can also be used to find the tweeter's optimal offset (to the backside) compared to the mid.
See also the mid cabinets at Troels site, they're all larger.
Best is to make a test cabinet for the mid only with a moveable backside so you can adjust the volume.
This test cabinet can also be used to find the tweeter's optimal offset (to the backside) compared to the mid.
Last edited:
The C168...990 measures quite terribly!
Accuton C168-6-990 CELL | HiFiCompass
The C30 isn't particularly good either...
Accuton C30-6-358 CELL | HiFiCompass
A whole lot of money for a whole lot of issues. You'd be better off using SBs metal or ceramic lines.
Accuton C168-6-990 CELL | HiFiCompass
The C30 isn't particularly good either...
Accuton C30-6-358 CELL | HiFiCompass
A whole lot of money for a whole lot of issues. You'd be better off using SBs metal or ceramic lines.
The C168-6-990 is much more sensitive than the SB17NBAC35-8,
to compare the hificompass graphs you need to set the Accuton at 2.83 and the SB acoustic at 5.6 to get about the same output.
The difference isn't that big.
If you don't need the extra sensitivity you can use the SB acoustics or for Accuton the very good C90-6-724
to compare the hificompass graphs you need to set the Accuton at 2.83 and the SB acoustic at 5.6 to get about the same output.
The difference isn't that big.
If you don't need the extra sensitivity you can use the SB acoustics or for Accuton the very good C90-6-724
Dan I take it you are still listening to your speakers. Like you I am looking for my last set of speakers. My apogee speakers are the best speakers that I have ever heard and I would rebuild them but my wife wants smaller speakers..
I am now rethinking and maybe going with the RAAL tweeter in my design hoping they will give me that magic I have with the apogees. Cost of drivers is secondary as I want to these speakers to compare to what I have now.
Since it has been few years since you have built your speakers and I am sure I would like to use accuton drivers with the RAAL would you pick a different mid driver or use the same mid? You mentioned the 11 " bass which I assume is S280-6-282 from accuton and I wondering if you would compare it to the 10" AS250-8-552
Also I am planning to go active with the Accuton DSP and I read Raal Lazy Ribbon 9" Ribbon Tweeter would need a large capacitor for active and wondering if the ribbon you selected would also need the capacitor.
I am now rethinking and maybe going with the RAAL tweeter in my design hoping they will give me that magic I have with the apogees. Cost of drivers is secondary as I want to these speakers to compare to what I have now.
Since it has been few years since you have built your speakers and I am sure I would like to use accuton drivers with the RAAL would you pick a different mid driver or use the same mid? You mentioned the 11 " bass which I assume is S280-6-282 from accuton and I wondering if you would compare it to the 10" AS250-8-552
Also I am planning to go active with the Accuton DSP and I read Raal Lazy Ribbon 9" Ribbon Tweeter would need a large capacitor for active and wondering if the ribbon you selected would also need the capacitor.
Yes, they're still my main speakers and are still candidate for my final speakers 
Even more with the version 2 I've built.
For version 2 I used the same drivers but different cabinets, especially the mid cabinet was optimized for absorbing the backwave.
If I would change the mid driver?
I don't know, because mine are passive I really like/need the high sensitivity of the C173-6-090, it matches my double 10" woofers (parallel=96db).
Also the C173-6-090 has almost no cone breakup,
the only other high sensitive candidate would be the C168-6-990, that open back looks great.
For the tweeter I would like to try the new Viawave GRT145 instead of the Raal, just out of curiosity, the Raal still sounds great.
The GRT-145 has very low distortion, see this test.
No idea about those Accuton woofers, the 8" ceramic woofers from SB acoustics also look good.
For DSP also check out the freeDSP-aurora DSP, looks like a nice candidate for a good DSP
Regards,
Danny
Even more with the version 2 I've built.
For version 2 I used the same drivers but different cabinets, especially the mid cabinet was optimized for absorbing the backwave.
If I would change the mid driver?
I don't know, because mine are passive I really like/need the high sensitivity of the C173-6-090, it matches my double 10" woofers (parallel=96db).
Also the C173-6-090 has almost no cone breakup,
the only other high sensitive candidate would be the C168-6-990, that open back looks great.
For the tweeter I would like to try the new Viawave GRT145 instead of the Raal, just out of curiosity, the Raal still sounds great.
The GRT-145 has very low distortion, see this test.
No idea about those Accuton woofers, the 8" ceramic woofers from SB acoustics also look good.
For DSP also check out the freeDSP-aurora DSP, looks like a nice candidate for a good DSP
Regards,
Danny
Last edited:
I read Troels review and the Viawave appears to be a good choice also. I will spend a bit of time researching both ribbons before I decide. Nice to know that you still like the Raal. As far as mid you appear to like both of Accutons that I considered and the C168 was the one I last was thinking of using so I think I will stick with it
As far as DSP I have already purchased the Accuton boards and waiting for them to arrive so that I can build it into a case.
Your speakers look excellent and I hope that I am able to build something that looks as good even though it is how they sound that really matters.
As far as DSP I have already purchased the Accuton boards and waiting for them to arrive so that I can build it into a case.
Your speakers look excellent and I hope that I am able to build something that looks as good even though it is how they sound that really matters.
The SB driver is cleaner than the accuton even at 11v2 or are you not seeing all the high order distortion products shoot up above 1kHz? That's certainly not my idea of a clean mid driver, needing a steep xover at around 1.2kHz to keep its issues at bay.
Update - Project is going slower than anticipated but I am in no hurry.
Drivers have changed and have now been purchased so they are finalized.
Tweeter - Raal 70-20XR
Mid C168-6-990
Bass 2-Accuton C220-12-222 wired in Parallel for each speaker.
Still separate closed boxes
Mid will be approx 10 lit
Bass is approx 65 lit before adding bracing
Presently installing Accuton DSP's in box. Once completed I plan to learn to use this with an old set of speakers since I have never worked with crossovers and there is not a lot of documentation for the DSP's available.
CNC is scheduled to be started in January and I will start posting pictures at that time.
Drivers have changed and have now been purchased so they are finalized.
Tweeter - Raal 70-20XR
Mid C168-6-990
Bass 2-Accuton C220-12-222 wired in Parallel for each speaker.
Still separate closed boxes
Mid will be approx 10 lit
Bass is approx 65 lit before adding bracing
Presently installing Accuton DSP's in box. Once completed I plan to learn to use this with an old set of speakers since I have never worked with crossovers and there is not a lot of documentation for the DSP's available.
CNC is scheduled to be started in January and I will start posting pictures at that time.
Notch the resonances at 8-10kHz in the C168-6-990 and methinks the distortion goes down. I think it's ridiculous to judge a drive based on raw measurements, fix the x-over and then measure.
Besides, it's silly going bonkers with extremely low distortion values. Who the hell will hear it when played in a room that adds gobs of crap. For me it seems a way to reinvent speakers in order to sell more and for the anal people that relish numbers just to feel subjectively good
Besides, it's silly going bonkers with extremely low distortion values. Who the hell will hear it when played in a room that adds gobs of crap. For me it seems a way to reinvent speakers in order to sell more and for the anal people that relish numbers just to feel subjectively good
Notch the resonances at 8-10kHz in the C168-6-990 and methinks the distortion goes down. I think it's ridiculous to judge a drive based on raw measurements, fix the x-over and then measure.
Besides, it's silly going bonkers with extremely low distortion values. Who the hell will hear it when played in a room that adds gobs of crap. For me it seems a way to reinvent speakers in order to sell more and for the anal people that relish numbers just to feel subjectively good
Hi Peter
I have a calibrated mic and been playing with REW to learn how to use the application as I am sure after I have these speakers built I will require some help fine tuning the crossover with the DSP. I have also playing with Sonarworks software because they are will to take the calibration file and convert it to FIR filters that I will be able to import into the DSP. I am also considering the application FIR Designer by Eclipse Audio to help with the final setup of the speakers. I really like the FIR designer because their DEMO will allow me to test the software and I will only need to purchase it if I want to export the settings to my DSP
I appreciate all comments as they help me to read and learn as I progress through this project.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.