Buy 2-3-4 cheap self powered sealed subwoofers, spread them around the room, let them handle 70-100hz down to 30-20hz.
10" B&C 10ps26 MID/BASS 100hz -1500hz -- Should be easy for a 300B to drive. Look at the fairly flat frequency response chart on the left side. ~$150
http://www.bcspeakers.com/PDF/PRD/10PS26.pdf\
Or even better: JBL 2012H if you can source one. 70hz-2000hz
http://www.jblpro.com/pages/pub/components/2012h.pdf
Lots of cookbook xover calculators on the web, here's one: 2-Way Crossover Designer / Calculator
Don't settle for audiophile approved thinking.
Have fun.
10" B&C 10ps26 MID/BASS 100hz -1500hz -- Should be easy for a 300B to drive. Look at the fairly flat frequency response chart on the left side. ~$150
http://www.bcspeakers.com/PDF/PRD/10PS26.pdf\
Or even better: JBL 2012H if you can source one. 70hz-2000hz
http://www.jblpro.com/pages/pub/components/2012h.pdf
Lots of cookbook xover calculators on the web, here's one: 2-Way Crossover Designer / Calculator
Don't settle for audiophile approved thinking.
Have fun.
Very useful crossover calculator - thanks for that.
I can't go too big with speakers or bring them out into the room because of the room size 14x11x9. So it's pretty much a tall thin cabinet up against the wall. I can go up to 4ft high - that's not a problem - so 45 litres is perfectly possible.
Andy
I can't go too big with speakers or bring them out into the room because of the room size 14x11x9. So it's pretty much a tall thin cabinet up against the wall. I can go up to 4ft high - that's not a problem - so 45 litres is perfectly possible.
Andy
tall and thin versus short and fat
The previous post had some good suggestions. You could look at a larger driver, more efficiency, and come up with a very good "short and fat" design. I like his suggestion of the JBL driver. Several of these can do well in small boxes, like 1 cubic foot. That would still leave you room for a good stand. I've the TAD's in such set-ups to good effect.
Unless you simply prefer tall and thin.
The previous post had some good suggestions. You could look at a larger driver, more efficiency, and come up with a very good "short and fat" design. I like his suggestion of the JBL driver. Several of these can do well in small boxes, like 1 cubic foot. That would still leave you room for a good stand. I've the TAD's in such set-ups to good effect.
Unless you simply prefer tall and thin.
Hi Andy, just happened on this thread. Now I see why you dropped me a mail the other day. The reply i gave was regarding the 18w4531's in a TL design. Those are the best speakers I have ever heard. That having been said, they are being driven by a 100w hybrid amp, not a small SET, so I can't vouch for the results in your setup. However, if it appeals to you, and you are genuinely interested in building it, I will happily share with you the details of the design.
Unhappy results with SET's and multi-way designs don't only come down to driver sensitivity, but also to output transformer design. I would recommend that you look into that aspect of things before deciding on drivers. If your transformers are decent quality and paricularly if they have a 4 ohm tap, then you might do well with the 18w4531's (90dB sensitivity), and a TL will give you a wonderful clear and open midrange and lovely tight bass. As far as tweeters are concerned, you can save yourself a lot of $$$ and headaches with crossover design by using a cheap ring-tweeter (Vifa or SB Acoustics) instead of the very pricey Scan that Zaph uses in his design.
Hope this helps,
William.
Unhappy results with SET's and multi-way designs don't only come down to driver sensitivity, but also to output transformer design. I would recommend that you look into that aspect of things before deciding on drivers. If your transformers are decent quality and paricularly if they have a 4 ohm tap, then you might do well with the 18w4531's (90dB sensitivity), and a TL will give you a wonderful clear and open midrange and lovely tight bass. As far as tweeters are concerned, you can save yourself a lot of $$$ and headaches with crossover design by using a cheap ring-tweeter (Vifa or SB Acoustics) instead of the very pricey Scan that Zaph uses in his design.
Hope this helps,
William.
I have used the 8545 but not the others. They are good drivers with no real problems. They have good midrange and are easy to cross over, and they can easily produce the bass you're asking for.
18W8535 works well in infinite baffle I have a pair in about a 20 liter cabinet with Q of about 0.8 and f3 of about 45 Hz.
The 18W8545 is also supposed to work in an infinite baffle - but works best with a smaller box and higher cutoff frequency.
However, I drive mine with a solid state amp. With a valve amp there is some output impedance and the Q of the system is raised. I would not like to try Q of over 0.8 so, either the 18W8535 with a cabinet of well over 20 liters or the 18W8545 with a cabinet of say about 20 liters. The Q of the system is going to depend on the output impedance of the amp (damping factor).
Nick
If space is at a premium, the 18w8545k models perfectly in a 14 litre vented cabinet (I have such speakers in my system right now). But having recently used the 18w4531's, I can tell you that they are very definitely superior to the 8545's and they are also more sensitive. (90dB versus 87.5dB). Their only drawbacks in your case may be their larger cabinet requirements and maybe your OPT is not good for driving 4ihm loads.
The 8545 has quite a nasty cone breakup which is audible and results in a tiring harshness unless you use at least a 2nd order crossover and also cross over fairly low, whereas the 4531 (and the 8531) have far less of a problem with this.
As a matter of interest, I have a friend who is driving 3 way Scan speakers, with passive crossovers, very successfully with a 300b amp (bass = 21w8555, mid= 18w8545k tweet = D2905-9700). There may be a bit of a difference to your 300b though, in that he has 2x300b's in parrallel per channel, and he designed his own OPT's to a very high spec.
The 8545 has quite a nasty cone breakup which is audible and results in a tiring harshness unless you use at least a 2nd order crossover and also cross over fairly low, whereas the 4531 (and the 8531) have far less of a problem with this.
As a matter of interest, I have a friend who is driving 3 way Scan speakers, with passive crossovers, very successfully with a 300b amp (bass = 21w8555, mid= 18w8545k tweet = D2905-9700). There may be a bit of a difference to your 300b though, in that he has 2x300b's in parrallel per channel, and he designed his own OPT's to a very high spec.
Hi. Check out the Zaph ZRT, Scanspeak 7" Revelator and Aircirc tweeter. Crossover is all worked out too!. I have all the parts brand new, ex. cabinets which can range from 20l sealed to 38 l vented. I'll give a good price vs getting from Madisound. I can be e-mailed directly at delphinj@aol.com
I wouldnt say 18w revelator is superior to clasics 18w. revelators may have more bass due diferent magnetic system and especialy spider. they also have better resolution up from 1.5k. nothing beats 18w8545 when it comes to weight and authority in lower midrange,higher bass (200-800hz) vocals and lower strings just have weighty and palpable presence with many modern drivers do not have
i wouldn call 8545 harsh properly implenented its just have sligtly more glare in midrnage if crossed to high.
eficienty of both revelator and clasic 18w are on the low side- 86db, and actuaaly 18w8545 is more eficient bu 0.5db or so. sensitivity of 4 ohm driver will be more comparing to 8ohms (if so we can compare special version of 18w4545 clasic carbon which have 96db at 800-3khz range and it will beat 18w8531 by 5-6db)
but thats says nothing on tube amp with fixed taps taps, you will need eficienty not sensitivity in that case.
18w8545 hard to beat in 100-1khz range
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Hi Andy,
I've used the 18W8531G00 in combination with a ceramic tweeter in a closed (!) 2-way bookshelf loudspeaker. In this design, I used a series-crossover filter. It works beautifully (lots of detail); I'm ashamed to say it's the most beautiful mid-high sound I've heard to date (there is probably better stuff out there, I just haven't heard it yet).
One thing I can recommend strongly with this midwoofer is to TIE IT DOWN to the cabinet. Over time, screws tend to loosen a bit due to all the vibrations and this makes a big difference in the performance of the midwoofer. I could hardly believe the difference when I tightened the screws and listened again. There is actually a manufacturer out there that allows the user him/herself to tighten the drivers' screws (I forgot the name); this now seems to make sense to me. But I think it's probably good enough to use nuts+screws instead of just simple woodscrews to mount your Revelators.
Greetz,
MatchASM
I've used the 18W8531G00 in combination with a ceramic tweeter in a closed (!) 2-way bookshelf loudspeaker. In this design, I used a series-crossover filter. It works beautifully (lots of detail); I'm ashamed to say it's the most beautiful mid-high sound I've heard to date (there is probably better stuff out there, I just haven't heard it yet).
One thing I can recommend strongly with this midwoofer is to TIE IT DOWN to the cabinet. Over time, screws tend to loosen a bit due to all the vibrations and this makes a big difference in the performance of the midwoofer. I could hardly believe the difference when I tightened the screws and listened again. There is actually a manufacturer out there that allows the user him/herself to tighten the drivers' screws (I forgot the name); this now seems to make sense to me. But I think it's probably good enough to use nuts+screws instead of just simple woodscrews to mount your Revelators.
Greetz,
MatchASM
I have 18w 8545k speakers for many years now. If it is a heavier sound you want, then you might like them better, but I have recently built speakers with 18w 4531 drivers and had the chance to do A-B comparisons in my system for a few weeks and there is just no competition. If I had the bucks I would get rid of mine and build some with 4531's in a heartbeat. They just have way less distortion, almost no cone breakup modes, finer resolution of ambient detail and subtle harmonic information, all of which makes them perfect for well-recorded acoustic instuments. Good jazz recordings sound as if the musicians are in the room with you. But make no mistake, they can rock too! My 8545's sound clumsy next to them.
I did consider the ZRT, but the price of the Aircirc tweeter is very steep, especially considering it needs impedence bump compensation with electrolytic caps (or megabucks film caps). I used the SB Acoustics ring tweeter instead and it is absolutely outstanding. If the aircirc is any better, it can't be by much. SB goes down to 600hz, allowing first order x-over at normal x-over frequencies. Vifa is also good, but has a little bit of distortion just below 2000hz. Fine if you cross high, but not ideal for a two-way design.
I did consider the ZRT, but the price of the Aircirc tweeter is very steep, especially considering it needs impedence bump compensation with electrolytic caps (or megabucks film caps). I used the SB Acoustics ring tweeter instead and it is absolutely outstanding. If the aircirc is any better, it can't be by much. SB goes down to 600hz, allowing first order x-over at normal x-over frequencies. Vifa is also good, but has a little bit of distortion just below 2000hz. Fine if you cross high, but not ideal for a two-way design.
If you`re looking for a 2 way floorstander you`ll need a serious 8" woofer. The Revelator is the obvious choice as it has better bass than any other 8" on the market and it can play up to 2-2.5Khz with a low order filter. I completely agree with Elviukai but for the better bass of the 18W Classic - I have compared it to the Revelator side by side on the same setup and the Revelator was deffinitely better in all areas. The story changes if you need a solid bass driver - I think the 25W Classic is probably the best woofer on the market now, better than the Revelators of that size.
I built a 2-way with the Revelator 18W/4531G00 and the Vifa XT25TG tweeter, It is not completely finished as I have to get done with my house renovation first, so I don`t have measurements yet nor I have finished the external look of the speaker. If you want to know more about it - ask, I will provide a few details and observations based on listening:
The speaker is a 2-way built with a sandwich of plywood and MDF. Wall thickness is a total of 40mm - 16mm plywood on the inside plus 24mm MDF. Front panel is 56mm MDF reinforced with soild wood. It is covered in black leather and has angled edges. Inside the box, there is a frame of solid wood, but I think with such wall thickness this is not needed. Time alignment is physical, by 22mm. Tweeter is mounted with no rear chamber, but I will be adding one soon for aesthetics
Woofer is sealed, 20l ( design software suggested 14l for a Q = 0.707, but I noticed a much better bass and midrange presentation in a bigger box, the same will be if you go vented, the Revelator likes big boxes and will do its best in 37-38l ), damping is by a sandwich of felt + sheep wool which appeared to absorb vibrations better than anything else I tested. Backside has a special "spike" shape to reduce back wall reflections. The rest of the speaker is filled with 0.4mm quartz sand and thus the weight goes to a little over 100kg per speaker. The baffle is angled and woofer is just one, so BSC was needed, it is aprox. 4db in my case and I find it optimal in my room. This gives a total sensitivity of about 83db/W so If you want to follow my project, you have to look at push pull tube amps or solid state.
The crossover is a 2nd order Bessel at 2Khz. Below you will see the version I listen now, but it shows a little reduction on the 1.7-2Khz region and I would be testing a reworked version with 0,68mH and 9,2uF soon. Tweeter attenuation is not enough, so I will be going to 1.8ohm/4.7ohm.
Now, despite of what some people say, I did a comparison of a Visaton round wire coil and a Goertz copper foil, both of close sq. area - use foil coils or you`ll loose detail and buy the coils with the largest square area as possible ( 12AWG I think ).
My camera battery died, but i got at least one pic If you want the plans of this project, let me know, I`ll do some measurements and you`ll have them
I built a 2-way with the Revelator 18W/4531G00 and the Vifa XT25TG tweeter, It is not completely finished as I have to get done with my house renovation first, so I don`t have measurements yet nor I have finished the external look of the speaker. If you want to know more about it - ask, I will provide a few details and observations based on listening:
The speaker is a 2-way built with a sandwich of plywood and MDF. Wall thickness is a total of 40mm - 16mm plywood on the inside plus 24mm MDF. Front panel is 56mm MDF reinforced with soild wood. It is covered in black leather and has angled edges. Inside the box, there is a frame of solid wood, but I think with such wall thickness this is not needed. Time alignment is physical, by 22mm. Tweeter is mounted with no rear chamber, but I will be adding one soon for aesthetics
Woofer is sealed, 20l ( design software suggested 14l for a Q = 0.707, but I noticed a much better bass and midrange presentation in a bigger box, the same will be if you go vented, the Revelator likes big boxes and will do its best in 37-38l ), damping is by a sandwich of felt + sheep wool which appeared to absorb vibrations better than anything else I tested. Backside has a special "spike" shape to reduce back wall reflections. The rest of the speaker is filled with 0.4mm quartz sand and thus the weight goes to a little over 100kg per speaker. The baffle is angled and woofer is just one, so BSC was needed, it is aprox. 4db in my case and I find it optimal in my room. This gives a total sensitivity of about 83db/W so If you want to follow my project, you have to look at push pull tube amps or solid state.The crossover is a 2nd order Bessel at 2Khz. Below you will see the version I listen now, but it shows a little reduction on the 1.7-2Khz region and I would be testing a reworked version with 0,68mH and 9,2uF soon. Tweeter attenuation is not enough, so I will be going to 1.8ohm/4.7ohm.
Now, despite of what some people say, I did a comparison of a Visaton round wire coil and a Goertz copper foil, both of close sq. area - use foil coils or you`ll loose detail and buy the coils with the largest square area as possible ( 12AWG I think ).
My camera battery died, but i got at least one pic
If you want the plans of this project, let me know, I`ll do some measurements and you`ll have them Attachments
The cabinet is full of quartz sand to dampen vibrations and kill resonances. The effective chamber area is approx. 20l. I found some pics, one is of the backside, the test crossover is seen, the second is during the build so you could see the damping and wall thickness. Third is the pair of speakers in the storage room.
BTW: Sorry for the pic quality, I`ve done them with my phone...
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