I have two couple of speakers, JBL4311b I bought as a teen and JBL L220 I have since 2-3 years, suspensions renewed and crossover updated, former 91db latter 90db efficiency, driving them with 45W KT88 and the L220 sound amazing, I switched to solid state but 25W Class A are on the edge and also the dimensions of the JBL are way too important for my listening room.
I am chasing a friend who owns Sonus Faber Electa Amator II who wants to upgrade but he is too much of a thinking back and the curiosity to know about DIY kicked in, I know you can't expect a bookshelf to sound like my L220 (amazing speakers for their age!) and even my friend coupled the SF with a subwoofer but what about efficiency, is there anything which can reach 92-93dbW/m on a bookshelf size?
Grazie
I am chasing a friend who owns Sonus Faber Electa Amator II who wants to upgrade but he is too much of a thinking back and the curiosity to know about DIY kicked in, I know you can't expect a bookshelf to sound like my L220 (amazing speakers for their age!) and even my friend coupled the SF with a subwoofer but what about efficiency, is there anything which can reach 92-93dbW/m on a bookshelf size?
Grazie
Depends on how low it needs to be this high and box size/shape limitations, i.e. 92 dB = 1% eff., so look at these charts to find box size versus F3.
Attachments
https://www.salksound.com/model.php?model=Exotica+Monitors
^ measurements spec 92dB 52Hz F3
https://solen.ca/en/products/seas-exotic-2way-loudspeaker-kit
https://www.madisoundspeakerstore.com/approx-8-woofers/seas-exotic-w8-x2-08-8-woofer-alnico-magnet/
https://www.madisoundspeakerstore.c...-exotic-t35-x3-06-tweeter-with-alnico-magnet/
^ measurements spec 92dB 52Hz F3
https://solen.ca/en/products/seas-exotic-2way-loudspeaker-kit
https://www.madisoundspeakerstore.com/approx-8-woofers/seas-exotic-w8-x2-08-8-woofer-alnico-magnet/
https://www.madisoundspeakerstore.c...-exotic-t35-x3-06-tweeter-with-alnico-magnet/
Remember 1/4 or 1/2 space placement will extend the bass.. That is if they are placed on a bookshelf and not called a bookshelf just because they are a small cabinet then you will see gain.. Think Roy Allison 😀
You could have a passive & active design.
Passive >150 Hz (..this could be 92 db)
Active (and boosted low-end) <150 Hz
-and still achieve a small form-factor. Loudness would be a limiting factor though, and you would need a few midbass drivers with low Vas and good Xmax. The Active amplifier could be a common subwoofer plate-amp.
I think the obvious solution is 2.1 channels. Don't bother trying to handle < 100Hz on the bookshelf, and put a sub away in a corner some place.
Nope; physics, it's the law! 😉 As others have noted though, there's some options if you've got some size, location, budget flexibility.
Yes you can. Also 100db/W/m.
However, the question cannot be asked in this way, since the higher the efficiency at a given volume, the higher the lowest cut-off frequency.
For a high efficiency satellite box the mentioned drivers in post #13 under
https://www.diyaudio.com/community/...ge-model-studio-5m-100-db-and-92-5-db.206391/
are of interest.
I have wondered about this - my mental gymnastics has often thought about a bookshelf bipole (opposed drivers on opposeite sides) in push-push will mostly eliminate baffle step loss because the woofer acts like an omni. So find a pair of 89dB sensitive 16ohm drivers and connect in parallel (+6dB) as a bipole. Add tweeter of choice and design speaker as circa 95dB at 2.83v and 8ohms. In reality, there will still be losses so maybe conservatively, it will be 92-93dB at 2.83v at 1m.
Faital Pro 5FE120 16ohms comes to mind. Two in a 0.4 cu ft (11.3 L) cabinet might be able to get 60Hz F3?
If you don't mind driving 4 ohm load, parallel two 8ohm drivers as bipole.
I have used dual 3FE25-16 (91dB) in parallel on a mini Karlsonator and get 91dB sensitivity on those (still have -6dB baffle step loss as they are not bipole) - about 65Hz bass extension. But, 91dB is still excellent and lets me drive it with some smaller amps easily.
Faital Pro 5FE120 16ohms comes to mind. Two in a 0.4 cu ft (11.3 L) cabinet might be able to get 60Hz F3?
If you don't mind driving 4 ohm load, parallel two 8ohm drivers as bipole.
I have used dual 3FE25-16 (91dB) in parallel on a mini Karlsonator and get 91dB sensitivity on those (still have -6dB baffle step loss as they are not bipole) - about 65Hz bass extension. But, 91dB is still excellent and lets me drive it with some smaller amps easily.
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^you still run-into problems with Vas and low freq. extension.
You could of course go with an Isobaric design to halve Vas, but doing that substantially cuts-into Sensitivity.
Basically you won't get eff., low freq. extension, and low cabinet volume - without actively boosting the low-end in a small volume design to "reach" the more efficient drivers for your mid. and tweeter.
You could of course go with an Isobaric design to halve Vas, but doing that substantially cuts-into Sensitivity.
Basically you won't get eff., low freq. extension, and low cabinet volume - without actively boosting the low-end in a small volume design to "reach" the more efficient drivers for your mid. and tweeter.
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Has the OP stated how low the speaker needs to go and how big it can be? That was post #2 and really all we need to know.
Isobaric bipole bookshelf. That's 4 woofers in the cabinet. That doesn't leave much room for the actual cabinet.^you still run-into problems with Vas and low freq. extension.
You could of course go with an Isobaric design to halve Vas, but doing that substantially cuts-into Sensitivity.
Basically you won't get eff., low freq. extension, and low cabinet volume - without actively boosting the low-end in a small volume design to "reach" the more efficient drivers for your mid. and tweeter.
The think is my listening room is small and the L220 are huge, I like how they sound and for electronic music they are so very nice, 80s/90s rock, house and stuff like that but I wanna switch to something less intruding and even more prone to voices like jazz and such, I have a freshly done FW F4 and its 25W don't quite make it with the L220 so I'd move them to another place along with the 45W tube amp and look towards speakers which can delivery with the 25W that's why I ask about 92-93db and I understand I can't expect deep bass with small boxes but I heard my friend's SF Electa Amator II, with big amp from Jeff Rowland, and liked the sound but, again, they won't make it with 25W or maybe they could in a close listening environment.
Grazie
Grazie
Small room is good candidate for small bookshelfs with subwoofer.
Once you decide that you use sub for low frequencies, you have chance to achieve efficiency you desire in bookshels because you no longer need low fr extension there.
Once you decide that you use sub for low frequencies, you have chance to achieve efficiency you desire in bookshels because you no longer need low fr extension there.
3-way (not having to deal with upper freq. response), so perhaps Wilson Benesch mounting?
Even then though, still a tremendous struggle (..and one or more passive radiators taking up a bit more room).
It's just easier to allocate more volume (make the cabinet *deeper) and select a better driver for task.. OR go the active bass/sub route and cut the monitor's low-freq. somewhere above 100 Hz.
*it doesn't even require a wider baffle (side-mount the woofer) - so the front profile of the cabinet doesn't have to look much larger than a typical Monitor design.
BTW, the 10PR330 looks good with 35 liters and 40 Hz tuning freq. (mounted on the "outside" side-panel), and should provide good dynamic capability with enough eff. for baffle-step loss. That along with a capable eff. midrange and tweeter should make for something more than competitive with many JBL designs.
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I just got the FW F4 done and realised that 25W with the 20db output of my vintage AR SP9 are not enough to drive the also vintage JBL L220, I am collecting components to build the BA-3 based preamp which should add a few db to make so it gets loud enough but the plan still is to add a couple of bookshelves and delegate the L220 to another room and sell the 4311b to save space.
With these constraints I need high efficiency, I will try and read the thread posted above but now I am short on time, my friend was to sell his beautiful SF Electa Amator II with a sub (don't remember brand/model) but he keeps changing his mind so, in perspective, I am thinking of a different solution with dimensions not exceeding the Sonus Faber and no mind a sub to take care of bass frequencies unless I can get a decent SPL with the 25W of the F4.
Music generes a little bit of everything, if I feel so the L220 do their dirty job with the KT88 push-pull (whose sound I like), I wanna make a newer setup with the F4, the BA-3, digital source (a DAC to come to replace my actual Beresford Caiman SEG) and that's it.
This community rocks!!!
With these constraints I need high efficiency, I will try and read the thread posted above but now I am short on time, my friend was to sell his beautiful SF Electa Amator II with a sub (don't remember brand/model) but he keeps changing his mind so, in perspective, I am thinking of a different solution with dimensions not exceeding the Sonus Faber and no mind a sub to take care of bass frequencies unless I can get a decent SPL with the 25W of the F4.
Music generes a little bit of everything, if I feel so the L220 do their dirty job with the KT88 push-pull (whose sound I like), I wanna make a newer setup with the F4, the BA-3, digital source (a DAC to come to replace my actual Beresford Caiman SEG) and that's it.
This community rocks!!!