So, project advances. I moved to my new apartment last weekend. The listening room is tiny, but it'll do. I started from the acoustic side first, and bought 2 1500x1200x100mm acoustic panels to treat high- and midrange. One panel will be behind the chair, the other likely between the speakers. Roof installation would be great, but I cant make any mounting holes to the roof. Here are tech specs from the 50mm version of the same panel, I bought the coated version:
Because the primary problem with the small room is the bass, I will also build a bass trap to the right corner next to the window. The other corner is occupied by a bookself full of books, so it should also provide good damping. The material for the trap will be tube insulation made of compressed rockwool. It fits a 200mm tube, the wall thickness is 100mm. Total lenght of tube will be 2400mm. The surface is aluminum film. I will seal it with plastic to prevent fibers and smell leaking to room air. Looks like this:
On the other corner the entry door will be open, leading to rest of the apartment, about 40m2 of room spaces.
An externally hosted image should be here but it was not working when we last tested it.
Because the primary problem with the small room is the bass, I will also build a bass trap to the right corner next to the window. The other corner is occupied by a bookself full of books, so it should also provide good damping. The material for the trap will be tube insulation made of compressed rockwool. It fits a 200mm tube, the wall thickness is 100mm. Total lenght of tube will be 2400mm. The surface is aluminum film. I will seal it with plastic to prevent fibers and smell leaking to room air. Looks like this:
On the other corner the entry door will be open, leading to rest of the apartment, about 40m2 of room spaces.
Mayuri,
Good to see you getting settled in new apartment and preparing to make this speaker again. Seeing that you are going with 10F/8424 FAST, you might be interested in my recent passive XO with RS225-8. It needed working out very well for time alignment. By simply flipping speaker cabinet upside down so tweeter is below woofer and takes more time of flight to reach ears. No waveguide or recessed full range needed. The XO was quite simple too and originally developed for FF85WK but interchangeable with 10F. Measurements look great and sounds wonderful.
http://www.diyaudio.com/forums/full...-rs225-8-fast-ref-monitor-68.html#post4743530
Pretty well behaved flat phase:
Impulse and step:
I have a Dagger sealed TL rear chamber on 10F. About 1.3liters.
On the other hand, I am starting my reference 3-way passive speaker design here:
http://www.diyaudio.com/forums/multi-way/297171-rs28f-rs180p-b80-hole-filler-3-way.html
Tweeter is getting a waveguide. B80 mid as hole filler XO:
Good to see you getting settled in new apartment and preparing to make this speaker again. Seeing that you are going with 10F/8424 FAST, you might be interested in my recent passive XO with RS225-8. It needed working out very well for time alignment. By simply flipping speaker cabinet upside down so tweeter is below woofer and takes more time of flight to reach ears. No waveguide or recessed full range needed. The XO was quite simple too and originally developed for FF85WK but interchangeable with 10F. Measurements look great and sounds wonderful.
http://www.diyaudio.com/forums/full...-rs225-8-fast-ref-monitor-68.html#post4743530
Pretty well behaved flat phase:
Impulse and step:
I have a Dagger sealed TL rear chamber on 10F. About 1.3liters.
On the other hand, I am starting my reference 3-way passive speaker design here:
http://www.diyaudio.com/forums/multi-way/297171-rs28f-rs180p-b80-hole-filler-3-way.html
Tweeter is getting a waveguide. B80 mid as hole filler XO:
Last edited:
Hello xrk,
Thanks for the tip on the crossover and a nice project you have ongoing. However, I'm pretty much set on using biamping with line level crossover for the project. Either 1st order PLLXO or a 4th order LR4 (depends which sounds better to me) 🙂
For time alignment I'll go with slanted front panel along with a flush mounted FR driver. If that's not enough, a shallow 45 degree "waveguide" on FR is also possible to set it further back.
Going to plan the cabinets to completion this week and order the boards. Next week is holiday so I've got some spare time to build 😀
Thanks for the tip on the crossover and a nice project you have ongoing. However, I'm pretty much set on using biamping with line level crossover for the project. Either 1st order PLLXO or a 4th order LR4 (depends which sounds better to me) 🙂
For time alignment I'll go with slanted front panel along with a flush mounted FR driver. If that's not enough, a shallow 45 degree "waveguide" on FR is also possible to set it further back.
Going to plan the cabinets to completion this week and order the boards. Next week is holiday so I've got some spare time to build 😀
If you're listening mid/far field and off axis at all, consider adding tweeters to the 10F......although a wonderful driver for nearfield and a smooth response, they do beam like crazy above 8khz which makes for a terribly off balanced power response once you're listening to the speaker and the room.
Remember, constant directivity doesn't mean narrow or wide as what waveguides, horns and synergy's do.....it means constant where the directivity is 'even' over the widest range possible. This isn't possible with high frequency content and drivers larger than around 1 1/4" and direct radiators.
Since you're looking for a corner system, you've actually stepped into the best possible setup.........see Wayne Parnham and his Pi speaker thinking with corner mid horns.
Remember, constant directivity doesn't mean narrow or wide as what waveguides, horns and synergy's do.....it means constant where the directivity is 'even' over the widest range possible. This isn't possible with high frequency content and drivers larger than around 1 1/4" and direct radiators.
Since you're looking for a corner system, you've actually stepped into the best possible setup.........see Wayne Parnham and his Pi speaker thinking with corner mid horns.
Thanks for the tip mayhem! I'll wait a good deal on second-hand tweeters before I go off to buying something new. I spared a nice chunk of money by buying both the SLS-12 and 10F/8424 second-hand (both are still in packages though, the 10F had been used exactly once for a measurement before I bought it).
My listening distance will be approximately 230cm or just under 8ft. I'm unsure if this would classify as near- or farfield listening. Adding a tweeter is certainly a possibility with the 10F providing area between 350Hz and 8kHz. I'll make the enclosures modular anyhow, with the top cabinet attached with elastic silicone. This allows me to make further changes to the design without demolishing the bass cabinet below.
Also as a note, the corner system is scrapped for the moment. These will be on the side wall. I attached the current plan.
My listening distance will be approximately 230cm or just under 8ft. I'm unsure if this would classify as near- or farfield listening. Adding a tweeter is certainly a possibility with the 10F providing area between 350Hz and 8kHz. I'll make the enclosures modular anyhow, with the top cabinet attached with elastic silicone. This allows me to make further changes to the design without demolishing the bass cabinet below.
Also as a note, the corner system is scrapped for the moment. These will be on the side wall. I attached the current plan.
I think your current driver arrangement would work very nice in that space and orientation. I'd OB the 10F for sure!
Doesn't OB require a lot of empty space behind it? These speakers will be placed directly against the wall, so the maximum distance would be very short.
Last edited:
OB doesn't sound good if they are too close to a wall. Maybe you should try something like this:
http://www.linkwitzlab.com/LXmini/Introduction.htm
😉
http://www.linkwitzlab.com/LXmini/Introduction.htm
😉
Ordered the plywood today. I will build speakers similar to these:
The bigger pyramidal-shaped enclosures with elastic bonds would be nice, but little birds sang that the WAF is quite low for big speakers in a small room that you still have to angle inwards from the wall. So, in a sense, the models which sit nicely on the wall already angled inwards and are quite flat seem smart to build 😀
An externally hosted image should be here but it was not working when we last tested it.
The bigger pyramidal-shaped enclosures with elastic bonds would be nice, but little birds sang that the WAF is quite low for big speakers in a small room that you still have to angle inwards from the wall. So, in a sense, the models which sit nicely on the wall already angled inwards and are quite flat seem smart to build 😀
You can certainly go a long ways with a FAST. These are particularily good:
Alpair 12pWeN in a Woden ML-TL with A7.3eN as midTweeter. We started with A7PeN, but prefer the metal cone. You could use any number of midTweeters.
I haven't heard the Visaton, but we have the Scan 10F and while good, the 2 drivers we have used as midTweeters in our FASTs perform better.
I have yet to hear a line array that really grabs me.
dave
That reminds me of the PALO, not sure if that is the right name, with two woofs and a tweet.
So, got a couple second-hand tweeters:
Bohlender Graebener NEO3 PDRW ribbon:
http://www.juoiga.eu/images/datasheets/neo3pdr_white_paper.pdf
Scan-Speak D20120/851300 3/4" textile dome:
http://www.scan-speak.dk/datasheet/pdf/d2010-851300.pdf
Both seem more than decent. I'll test and measure the speaker with 10F/8424 first, then decide if a tweeter is necessary for the very top end. Hunting these second-hand deals is fun 😀
Bohlender Graebener NEO3 PDRW ribbon:
http://www.juoiga.eu/images/datasheets/neo3pdr_white_paper.pdf
Scan-Speak D20120/851300 3/4" textile dome:
http://www.scan-speak.dk/datasheet/pdf/d2010-851300.pdf
Both seem more than decent. I'll test and measure the speaker with 10F/8424 first, then decide if a tweeter is necessary for the very top end. Hunting these second-hand deals is fun 😀
Since I haven't posted any progress pictures in a long time, here's three:
My listening chair and still unfinished acoustic panel behind it. I decided to put it the non-coated side up, as it gives overall a smoother absorbance spectrum (see manufacturer promises on the previous page). It will be hanged from behind the chair so the low end will be at head height.
The bass trap. 400mm tube of rockwool used for ventilation tube insulation. It has a aluminum foil surface, but I decided to leave it on the plastic packaging. One finnish hobbyist did extensive research on similar materials, and found out that it only increases the mid-range and decreases the bass absorption if you take the plastic out ALONG with potentially releasing rockwool fibers onto the air. I've fixed all the potential leaks with aluminum construction tape and checked with pressure test that it's sealed. Every wifes/girlfriends dream to have one of these in the room!
The drivers. Optional tweeter is the Scan-Speak D20120/851300 3/4" textile dome. Crossed over from around 300-500Hz is the Scan-Speak 10F/8424G00 full range driver. The low end of the audio bandwidth will be handled by Peerless SLS 12" 830669.
My listening chair and still unfinished acoustic panel behind it. I decided to put it the non-coated side up, as it gives overall a smoother absorbance spectrum (see manufacturer promises on the previous page). It will be hanged from behind the chair so the low end will be at head height.
The bass trap. 400mm tube of rockwool used for ventilation tube insulation. It has a aluminum foil surface, but I decided to leave it on the plastic packaging. One finnish hobbyist did extensive research on similar materials, and found out that it only increases the mid-range and decreases the bass absorption if you take the plastic out ALONG with potentially releasing rockwool fibers onto the air. I've fixed all the potential leaks with aluminum construction tape and checked with pressure test that it's sealed. Every wifes/girlfriends dream to have one of these in the room!
The drivers. Optional tweeter is the Scan-Speak D20120/851300 3/4" textile dome. Crossed over from around 300-500Hz is the Scan-Speak 10F/8424G00 full range driver. The low end of the audio bandwidth will be handled by Peerless SLS 12" 830669.
If you or guests / family get respitory irritation in your listening space (cough, sore throat, stuffy nose, itching, etc), then the bass traps might release fibers into the room air. If not, then the curtain cloth is enough to hold the fibers at place 🙂
Never had those symptoms, so I guess it's fine.... even though that curtain cloth is quite thin.
Thanks!
Thanks!
- Status
- Not open for further replies.