I agree. We can nit-pick over some pros and cons of each driver, but either one is probably quite good.
Having said that, there can be only one. I can setup a formal poll if we want, but there aren't that many people following all of the details and I'd be a little concerned that literally 10 people not following the thread very closely could pick the driver. I'd prefer to hear peoples opinions and direct recommendations, but if you want a poll let me know.
The only one I know for sure is @motokok who votes for the SB12MNRX2. 😁
I have a preference for the SS 15W/4434G - but I am not sure how solid the logic is or if I fallen victim to audio myths. I feel that the 5" midrange (Sd = 80 cm2) is going to transition better from the SLS 12" (523 cm2) than the SB12MNRX2 (50 cm2) is going to. And also possibly reproduce low mids better with the larger cone. (And I accept that the directivity from the 5" to the tweeter will be a bit more of a challenge than a 4".) However, if I model the SB12MNRX it seems to be able to hit the SPL levels we need it to if paired with the SLS 12". Also, the 5" would go lower which would matter if we need it to, but again it would seem in this situation at least that the SB12MNRX2 can do what we are likely to ask of it. Curious as to what the real science/physics has to say versus my intuition.
Any thoughts on the above topic, as well as other arguments for and against the drivers is requested from all those following/contributing.
Arrangement of JBL L100 with port an knobs gives an overall impression that the woofer is not small. But if you look closely, The SD=60.
I personally have a revelator 15W8530 in a 2 way. Wich work pretty well.
But there is 2 compromise: lower end response. Not so good directivity matching at the top. A lot of little bookshelf are like this.
Keeping the same mid would "solve" the issue of Bass but not the directivity matching.
I do think that going 3 ways give the oportunity to reduce both compromise if we go with a lower SD. (waveguide could also be a solution for directivity but with lower dispersion). Now I realy don't know if going from 12" to 12cm could be an issue.
(my very personal taste would go for the 12mnrx2 because I already have speakers with 5.25 and 8inch mid and I'm curious to see what a little mid brings but it's clearly not objective !)
I personally have a revelator 15W8530 in a 2 way. Wich work pretty well.
But there is 2 compromise: lower end response. Not so good directivity matching at the top. A lot of little bookshelf are like this.
Keeping the same mid would "solve" the issue of Bass but not the directivity matching.
I do think that going 3 ways give the oportunity to reduce both compromise if we go with a lower SD. (waveguide could also be a solution for directivity but with lower dispersion). Now I realy don't know if going from 12" to 12cm could be an issue.
(my very personal taste would go for the 12mnrx2 because I already have speakers with 5.25 and 8inch mid and I'm curious to see what a little mid brings but it's clearly not objective !)
The SB likely matches a 25mm dome w/o waveguide better and from that pov alone it could be preferable. Attention however should be paid to the (electric) durability. Speakers like this get cranked up at parties. I’ve seen more than one (bass)midrange destroyed by heat in my life. Push X-over to 500Hz or higher, I’d advise.
I'd install a bypass for party mode only, deploying ptc's to ruin the dynamics when crowd gets intoxicated enough not
to notice it. Woofer may be at risk, mid and tw not likely, if x/o was any good.
to notice it. Woofer may be at risk, mid and tw not likely, if x/o was any good.
My preference goes to the SB12 because I like crossover Fc around 3200-3500Hz and it is easier to manage as you can use just a coil in the LP.
If you attach the frd/zma files of the SS and SBA I could do a simulation with them.
Most older 3-ways had very poor crossovers, often mid without highpass and woofer with just a coil.
The suggested 4-5" drivers can take enough spl/current with decent LR2 acoustic xo.
These DIY- speakers will most likely not be used as party speakers with 1000W cheap amps nowdays, IMO. Ready-made are dirty cheap...
The suggested 4-5" drivers can take enough spl/current with decent LR2 acoustic xo.
These DIY- speakers will most likely not be used as party speakers with 1000W cheap amps nowdays, IMO. Ready-made are dirty cheap...
If it becomes a ventilated system: I wouldn't be so sure about that. If the tuning frequency is not absurdly low, I recommend an active high-pass filter that protects the woofer below the tuning frequency. It's amazing how much you can gain in level stability with such a high-pass filter.
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My opinion is that you should take advantage of marketing strategy and reputation of the brands involved.
What do you think builders would be happier with?
Do not expect them to make decisions that you should make. 🙂
Do you remember Bubba Gump Shrimp Company?
Who payed advertising for it? Not the company itself, that's for sure.
Imagine it's 1960's and you are designing a Ford GT, the one that will beat the Ferrari.
I am leaning towards the ScanSpeak 15W. It will be more tolerant of a low crossover (300 Hz range) than the SB12, and since we do not have a measured Peerless woofer response, we do not yet know what the big Peerless can do. Maybe it is happy with a 400 Hz crossover (meaning it plays nice up to about 800 Hz), but perhaps it will be best utilized in a lower range? If that be the case, the Scanspeak is a better option. On the high side, the SB12MNRX could be crossed as high as 4k, but this is a capability we probably will not need. There are several excellent tweeters in the $40 - $90 range that can operate comfortably down to 2k. Both drivers are very nice for the price, but for this application, I like the 15W.
j.
JBL's 4312G studio monitor released in 2019 at US $2,500 a pair
The "JBL Classic" was was also released in 2019, has the physical resemblance of the JBL L100 released in the 1970s, but with all the fundamental engineering already having been done from the 4312G
(same woofer, same mid, same tweeter albeit different dome material- titanium instead of Alu/Mg)
With some cosmetic and perhaps minor XO changes: -the price was right to attract baby boomers and millennials audiophiles- at US $4,000
Here our friend @bikinpunk does his best to talk about the positives about it:
And now as DIYer we are going to follow marketing instead of engineering?
Rejecting science and dreaming of a return to better times sounds very familiar.
All the best!
The "JBL Classic" was was also released in 2019, has the physical resemblance of the JBL L100 released in the 1970s, but with all the fundamental engineering already having been done from the 4312G
(same woofer, same mid, same tweeter albeit different dome material- titanium instead of Alu/Mg)
With some cosmetic and perhaps minor XO changes: -the price was right to attract baby boomers and millennials audiophiles- at US $4,000
Here our friend @bikinpunk does his best to talk about the positives about it:
And now as DIYer we are going to follow marketing instead of engineering?
Rejecting science and dreaming of a return to better times sounds very familiar.
All the best!
Whatever you fellers finally decide on try and do a large group buy.
Heck if you could rustle up a minimum of 250 units you could get an OEM order from SB Acoustics
https://sbacoustics.com/product/6in-sb17nrxc35-8/
Heck if you could rustle up a minimum of 250 units you could get an OEM order from SB Acoustics
https://sbacoustics.com/product/6in-sb17nrxc35-8/
@tktran303 i don't understand your post. I don't think any body talked about following any marketing. And I think we are all talking about objective compromises, advantage and disadvantage.
Has an engineer, the first think that should be done is to check "state of the art" check pros and cons and then search how to improve it. That's what is done here ...
But if you have any "science" argument to show wich driver between scanspeak and sb is better for our purpose, please share it !
Has an engineer, the first think that should be done is to check "state of the art" check pros and cons and then search how to improve it. That's what is done here ...
But if you have any "science" argument to show wich driver between scanspeak and sb is better for our purpose, please share it !
They are sold at least on thlp soudimport and madison. No need a group buy ...
Link? Must be old stock It's a driver I personally like but no longer available here and only OEM now
For example: 9 available here
https://en.toutlehautparleur.com/speaker-sb-acoustics-sb17nrxc35-8-impedance-8-ohm-6-inch.html.
I would be surprised that THLP have old stock from 4 years ago ...
They probably stock them because they have big customers that use them. It's like the SB26STC. (plastic face plate) They always have them even if it is oem ...
Did you have a look at the sb17nrx2c35 that is the new version ?
https://en.toutlehautparleur.com/speaker-sb-acoustics-sb17nrxc35-8-impedance-8-ohm-6-inch.html.
I would be surprised that THLP have old stock from 4 years ago ...
They probably stock them because they have big customers that use them. It's like the SB26STC. (plastic face plate) They always have them even if it is oem ...
Did you have a look at the sb17nrx2c35 that is the new version ?
The new JBL is not as good as the speaker it tries to recreate, that was already known. And there are other better examples also like those from Warfe
And as DIY'er, we build the speaker we want. Some want state of the art tech, some want a certain look or feel, ... As long as the builder and listener is happy it's valid. So a big variation of speakers are build here, and that is ok. Not everybody needs to build a state of the art speaker, or wants that. And we can because there is no commercial pressure or need to be popular among the masses.
The goal was here to build a speaker that resemble the old very popular big monkey coffin speakers with a big woofer, a small mid and a dome tweeter, but make it better. Not to build studio monitors that are 100% optimised. That does not mean we don't want to get the max out of the concept.
But if you want the most advanced speaker arround, there are other treads covering that on this forum. So live and let live.
Regardless of the driver selected, the baffle/cabinet will have a large effect on the directivity.
A science based design would focus on SPL and directivity goals first, rather than drivers first.
Here's an example of a KEF employee, using off-the-shelf parts, but carefully consider baffle and cabinet construction.
Note the geometry of the baffle and the port position.
Carefully chosen geometry allows drivers to play as smoothly as they can, and match each other's radiation pattern: Here's the same SB15 driver (albeit CAC) and SB26CDC
Want it to play louder/cleaner?
Add two or three small 10" subwoofers underneath as stands, or separately, and XO at 120Hz.
Want higher sensitivity? Swap out the magnet with the one from the newly released L35-4
Erin's new reference speaker for tone. This is kind of standardisation that we need to fix the circle of confusion.
By ex-KEF engineer, IMHO near state of the art in directivity, midrange and treble distortion, and certainly affordable to DIY. Scalable too!
A science based design would focus on SPL and directivity goals first, rather than drivers first.
Here's an example of a KEF employee, using off-the-shelf parts, but carefully consider baffle and cabinet construction.
Note the geometry of the baffle and the port position.
Carefully chosen geometry allows drivers to play as smoothly as they can, and match each other's radiation pattern: Here's the same SB15 driver (albeit CAC) and SB26CDC
Want it to play louder/cleaner?
Add two or three small 10" subwoofers underneath as stands, or separately, and XO at 120Hz.
Want higher sensitivity? Swap out the magnet with the one from the newly released L35-4
Erin's new reference speaker for tone. This is kind of standardisation that we need to fix the circle of confusion.
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Well, everything in this world is a compromise. The best option from a technical pov doesn’t appeal, otherwise everyone would have multisub-cardioid satellite systems in adequately damped listening rooms.
So let’s continue our quest for a classic 12-4/5-1 monkey box here and not discuss about whether this would be the best option. It’s not and we know.
So let’s continue our quest for a classic 12-4/5-1 monkey box here and not discuss about whether this would be the best option. It’s not and we know.
Well @wafflesomd and I can only warn people about building big boxes of yesteryear, because we've already built them.
Based on research by Floyd Toole in the 1980s, this eventually became a standard in 2015, called the CEA/CTA2034A.
We implore the designers @A4eaudio and @hifijim to consider baffle enhancements, at the very least.
Based on research by Floyd Toole in the 1980s, this eventually became a standard in 2015, called the CEA/CTA2034A.
We implore the designers @A4eaudio and @hifijim to consider baffle enhancements, at the very least.
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