Hello Rabbitz,
I got the Scan Speaks at about 1.5x the costs of the Vifa tweeters. The times I heard the Revelator tweeters I liked them very much so I had to take this opportunity. The differences with the Vifa tweeter may be smaller then some people think, simply because the Vifa are already very good! But as you say, I try to get the most out of this very small cabinets.
These cabinets may not play very deep, but the bass they do give is very well defined. I tried a few subwoofers with them but everytime I had to disconnect these subs because I felt they could not offer the same bass quality in the lower notes as these little speakes do in the >60Hz range. (Note: this may well be related to bad bass acoustics of my small room).
I never heard this Seas tweeter you talk about but a few people on a dutch forum also like these. Another one I hear very good comments on is the new Peerless HDS tweeter.
Best regards,
Walt
I got the Scan Speaks at about 1.5x the costs of the Vifa tweeters. The times I heard the Revelator tweeters I liked them very much so I had to take this opportunity. The differences with the Vifa tweeter may be smaller then some people think, simply because the Vifa are already very good! But as you say, I try to get the most out of this very small cabinets.
These cabinets may not play very deep, but the bass they do give is very well defined. I tried a few subwoofers with them but everytime I had to disconnect these subs because I felt they could not offer the same bass quality in the lower notes as these little speakes do in the >60Hz range. (Note: this may well be related to bad bass acoustics of my small room).
I never heard this Seas tweeter you talk about but a few people on a dutch forum also like these. Another one I hear very good comments on is the new Peerless HDS tweeter.
Best regards,
Walt
Because i am a tart 
I have brought a proprietary vent tube.
It is 50mm internal diameter as i could not find one @ 47mm, can someone (Rabbitz maybe?) advise as to how long it needs to be.
I have tried to work it out myself using WINISD. to begin with i wanted to check as a datum but it does not correlate with information given on the drawing, I get a completly different length for the tuning frequency from the reference drawing (I get 8.91cm long for a 47mm ID tuned to 66Hz)
Or am i being too fussy?
Cheers, M
I have brought a proprietary vent tube. It is 50mm internal diameter as i could not find one @ 47mm, can someone (Rabbitz maybe?) advise as to how long it needs to be.
I have tried to work it out myself using WINISD. to begin with i wanted to check as a datum but it does not correlate with information given on the drawing, I get a completly different length for the tuning frequency from the reference drawing (I get 8.91cm long for a 47mm ID tuned to 66Hz)
Or am i being too fussy?
Cheers, M
Hi D1GGY
There's a formula in this post for altering port sizes.
http://www.diyaudio.com/forums/showthread.php?postid=754348#post754348
For a 50mm port use 89 for length. Different software gives different results (the design was not done in WinISD) plus it depends on the amount of fill and losses (QL) you pick.
There's a formula in this post for altering port sizes.
http://www.diyaudio.com/forums/showthread.php?postid=754348#post754348
For a 50mm port use 89 for length. Different software gives different results (the design was not done in WinISD) plus it depends on the amount of fill and losses (QL) you pick.
OK where to now?
Hi Guys,
My focus has now turned to this little speaker project now that i have finished my amplifier projects and am wondering wether to go any further at all...
My concern is a lack of bass these drivers produce, granted the mid range and top end sound good in my develpment enclosures, but, before i go for it with veneer etc etc I can't help feeling that i should stop and go for a three way (was this the intention?) or go for the proper enclosures, and ustilise a sub to reinforce the lower end?
I don't know what to do. What was the train of thought as far as the development of the "DIY reference speaker"
Cheers, M
Hi Guys,
My focus has now turned to this little speaker project now that i have finished my amplifier projects and am wondering wether to go any further at all...
My concern is a lack of bass these drivers produce, granted the mid range and top end sound good in my develpment enclosures, but, before i go for it with veneer etc etc I can't help feeling that i should stop and go for a three way (was this the intention?) or go for the proper enclosures, and ustilise a sub to reinforce the lower end?
I don't know what to do. What was the train of thought as far as the development of the "DIY reference speaker"
Cheers, M
Hi D1GGY
Yes, they don't produce too much bass. Which version are you building, the 5.2 litre or 9.5 litre. The design brief from the thread originator was a speaker that could be a good datum point that you could use as a comparison as you built more speakers. The other intent was a good newbie speaker that would sound good and could be built upon or tweaked. The reference title of the thread can be a bit misleading as it means a reference point.
They are designed for a small to medium sized room and I use mine in my office with great results, however, when I was building my new mains, they took on main duties with a sub each side using the Vifa 8" M22WR.... were not disgraced at all and beautiful sonics.
There are a few options.
Build the TLb using the drivers plus some more or with additional woofers as shown in this thread http://www.audiocircle.com/circles/index.php?topic=36363.0. BTW, he's very happy with the final result and worth a read to see what the TLb is capable of and how he's using them.
Build a 3-way using your existing parts but 3-ways can be a nightmare.
Build a 2.5-way using your existing parts but with a 6.5" or larger 0.5 woofer in it's own section of the box.... this is much easier than the 3-way and would only need the additional woofers and 2 inductors.
Add a subwoofer to each channel or 1 to start off with. I'm not talking about a Peerless XLS type sub driver but a 8"-10" music woofer that would be used in a 3-way such as the Vifa M22WR or Peerless 850146 style of drivers.
The last one is the path and evolution I took with my main speakers and have not regretted it.... no woofer xo problems as plate amps do the bottom and no high pass xo for the mid-woofer as it rolls of naturally at the bottom end due to the OB design. See the pic of the final speaker (Scan Speak not Vifa used).
As you can see, the minute D27/P13 combo can evolve into much bigger and better things. Don't give up on it and I'm sure other will have more suggestions.
Yes, they don't produce too much bass. Which version are you building, the 5.2 litre or 9.5 litre. The design brief from the thread originator was a speaker that could be a good datum point that you could use as a comparison as you built more speakers. The other intent was a good newbie speaker that would sound good and could be built upon or tweaked. The reference title of the thread can be a bit misleading as it means a reference point.
They are designed for a small to medium sized room and I use mine in my office with great results, however, when I was building my new mains, they took on main duties with a sub each side using the Vifa 8" M22WR.... were not disgraced at all and beautiful sonics.
There are a few options.
Build the TLb using the drivers plus some more or with additional woofers as shown in this thread http://www.audiocircle.com/circles/index.php?topic=36363.0. BTW, he's very happy with the final result and worth a read to see what the TLb is capable of and how he's using them.
Build a 3-way using your existing parts but 3-ways can be a nightmare.
Build a 2.5-way using your existing parts but with a 6.5" or larger 0.5 woofer in it's own section of the box.... this is much easier than the 3-way and would only need the additional woofers and 2 inductors.
Add a subwoofer to each channel or 1 to start off with. I'm not talking about a Peerless XLS type sub driver but a 8"-10" music woofer that would be used in a 3-way such as the Vifa M22WR or Peerless 850146 style of drivers.
The last one is the path and evolution I took with my main speakers and have not regretted it.... no woofer xo problems as plate amps do the bottom and no high pass xo for the mid-woofer as it rolls of naturally at the bottom end due to the OB design. See the pic of the final speaker (Scan Speak not Vifa used).
As you can see, the minute D27/P13 combo can evolve into much bigger and better things. Don't give up on it and I'm sure other will have more suggestions.
Attachments
Almost forgot another alternative which doesn't cost much and works a treat.... should get the bass into the high 40Hz.
http://www.diyaudio.com/forums/showthread.php?s=&threadid=94808
http://www.diyaudio.com/forums/showthread.php?s=&threadid=94808
I'm not familiar with the 831709 but from the datasheet, should work OK with a plate amp and fill in the bass.... I don't think they are paper weights 
...... how cruel.
The design of that speaker in the pic will be going up on my site next month (time permitting). A lot of the information will be able to be used (with some calcs and common sense) on other similar speakers using different drivers. BTW, this one was very expensive to build but I was lucky that I had most of the bits in various other speakers around the place. Had I had to buy it all in at once....
would have 
Just keep an eye on this page every now and then as it will eventually pop up.
http://www.rzaudio.com/design.htm
...... how cruel.The design of that speaker in the pic will be going up on my site next month (time permitting). A lot of the information will be able to be used (with some calcs and common sense) on other similar speakers using different drivers. BTW, this one was very expensive to build but I was lucky that I had most of the bits in various other speakers around the place. Had I had to buy it all in at once....
would have Just keep an eye on this page every now and then as it will eventually pop up.
http://www.rzaudio.com/design.htm
johngalt47
For the OW1, use the standard series crossover shown in post 179.
http://www.diyaudio.com/forums/showthread.php?postid=1005310#post1005310)
Change the values to L1=0.47mH, C1=7.5uF, R1=1R, tweeter connected with +ve polarity as drawn, impedance 6R8 min. Connect at all points shown on the diagram as it is a series not parallel crossover. The inductor needs to have a DCR < 0R28 which can be achieved by a 16 AWG inductor (about 0R21).
Do not use the AR crossover shown in post 180 as the SPL of the tweeter is too low for the network which means the resistor would be too low in value (<3R9) causing impedance problems.
For the OW1, use the standard series crossover shown in post 179.
http://www.diyaudio.com/forums/showthread.php?postid=1005310#post1005310)
Change the values to L1=0.47mH, C1=7.5uF, R1=1R, tweeter connected with +ve polarity as drawn, impedance 6R8 min. Connect at all points shown on the diagram as it is a series not parallel crossover. The inductor needs to have a DCR < 0R28 which can be achieved by a 16 AWG inductor (about 0R21).
Do not use the AR crossover shown in post 180 as the SPL of the tweeter is too low for the network which means the resistor would be too low in value (<3R9) causing impedance problems.
The formula is from the Loudspeaker Design Cookbook 6th Edition section 2.70.
http://www.carstereo.com/help/Articles.cfm?id=21
The formula posted is shown on one line and hence uses brackets and ^ (power) symbols.
Just check the power is correct in you calculations.... 4^3 is the same as 4³.
The other is to do the calculations in accordance with the sequence of the brackets ().
The other is to check the units of measurement... inches and not mm, cm, ft etc.
http://www.carstereo.com/help/Articles.cfm?id=21
The formula posted is shown on one line and hence uses brackets and ^ (power) symbols.
Just check the power is correct in you calculations.... 4^3 is the same as 4³.
The other is to do the calculations in accordance with the sequence of the brackets ().
The other is to check the units of measurement... inches and not mm, cm, ft etc.
Make sure they are wired exactly as per the schematic. Join the dots.
http://www.diyaudio.com/forums/attachment.php?s=&postid=1005310&stamp=1158256386
http://www.diyaudio.com/forums/attachment.php?s=&postid=1005310&stamp=1158256386
