SBA 741 vs. SBA 761 for Classical Music

I think what people are trying to say, IMO they’re absolutely right, for anything like classical music (or any music) you need the lower octave. You stand to gain a lot by having proper bass since your coming from full range and a small two-way. Scale and mid-range quality of music will be improved.

I have kairos (three way) with 1x 10” driver each side and craving more bass. I’m looking to build an SB 741, with a different approach to bass up to 200hz - more surface area.

I’d suggest the 741, improved midrange clarity not just due to driver size, also decreased mass to move, narrower baffle and bass is picked up by a dedicated driver. It also allows you to build an integrated active sub design later.

For the zing, I have found isolation and room acoustics can support transient response and micro details. I use sorbothane to reduce vibrations to the ground and I’d suggest acoustic panels for atleast the first reflection zones which made a significant impact to the zing effect.

I'm curious what you are looking for in another build that the Kairos 3-way does not give you now. It gets excellent reviews and is one of the alternatives that I have been looking at for my next build.

I've moved over my interest to the new Troels SBA 741 and 941 designs primarily due to the 4" midrange they incorporate. But I haven't totally discounted the Kairos if there is a compelling reason for choosing it. I'm very happy with Jeff Bagby's Piccolo within the limits of its capabilities. I believe he is an excellent designer and trust his work.
 
The SBA-761 utilizes the bigger (6.5in) and highly regarded mids driver MW16P. HifiCompass even tout is as one of his favorite drivers soundwise here:
Some speaker driver measurements...

Having built Troels' ScanSpeak 3-way Discovery classic, there are times I wonder; "would these sound even better with bigger mid drivers?". If you plan to incorporate active subs later, the SBA-761 might give you that extra oomph in the mids with it combining the MW16P and MW19P cone diameters.

Yes. This is exactly the direction I've been heading as well. The critical key is the 4" midrange, which most of the suggestions so far have not incorporated. They seem more concerned with the low end extension of the woofer than with the midrange. I'm going with Troels direction to use a 4" midrange unless I find a reason to change.

Thanks for bringing up the SEAS-3-Way-Classic-mkII. I had looked at it briefly, but had not continued since it's a proprietary design while the newer SBA 741 and SBA 761 are open with all crossover values publicly specified .

However, the use of the MCA 12RC in the mkII makes it certainly a possibility. Especially with the comment about very fast response to transient attacks. That might be the key to giving me the "kzing" that I'm looking for.

Not sure how the MCA 12RC compares to the Satori MR13P-8 used in the SBA 741 and 941 that he calls magnificent in the write up of the later. But certainly worth a look.
 
Last edited:
I'm curious what you are looking for in another build that the Kairos 3-way does not give you now. It gets excellent reviews and is one of the alternatives that I have been looking at for my next build.

I've moved over my interest to the new Troels SBA 741 and 941 designs primarily due to the 4" midrange they incorporate. But I haven't totally discounted the Kairos if there is a compelling reason for choosing it. I'm very happy with Jeff Bagby's Piccolo within the limits of its capabilities. I believe he is an excellent designer and trust his work.

I learnt some lessons in my implementation. I built the Kairos with translam cabinets and made some mistakes. I'm looking at the best type of cabinets and may go constrained-layer-damping, as I feel the drivers and design deserve the best cabinet of my capability. I also don't like the physical appearance of the boxy bass bins.

The speakers themselves, the design is excellent:
Although, my previous speakers were ATC SCM100's, and I feel they're slightly behind on mid-range clarity (very slightly). Overall I prefer the Kairos to the ATC apart from the bass. I'm hoping a 4" mid-range driver will get me closer. I would also like to use the BE tweeter, but the Kairos would require significant cross-over changes and finally, I want less stressed bass.

I think the SB741 + 12" or two 10" actively driven side-firing would be best for my needs and importantly room size.

I would suggest, before you build anything. Look at room acoustics first and try to borrow a subwoofer. Jeff Bagby is an awesome designer and those piccolo's could probably get a bit further with bass reinforcing them and sorting out the room. I'd imagine the piccolos won't be miles behind the Satori designs.

Like you, I also like the idea that it is an open design.
 
I have owned a great many speakers and am yet to work out what makes a good classical music speaker.I have the Kairos [both 2 and 3 way version] and do not think it is that good on classical.My Sonus Faber Cremona Auditor Ms were a lot better [especially for string tone].Some old B&W DM2s transmission lines were nearly very good as were some JBL Studio 590s and of course for orchestral music Bose 901s when set up properly can sound fantastic if a bit coloured and lacking in refinement.Then my Yamaha NS75Ts are superb on piano and the best speakers I have owned for that instrument.And yet all these speakers would appear to have nothing in common.So really speculating on what might sound good based on components or configuration is probably a waste of time.
If you want the best just buy a pair of Yamaha NS 5000s.The most real and convincing speakers I have ever heard for voice and acoustic instruments.
 
If you want CLEAN-CLEAN-CLEAN sound, you need speakers which control directivity, or room treatment which controls reflections.

These two white papers from Dr. Earl Geddes explain the benefits of controlled directivity speakers in modest size home listening rooms.
http://www.gedlee.com/Papers/directivity.pdf
http://www.gedlee.com/Papers/Philosophy.pdf

-With a standard dome tweeter, take a second look at a sealed 12" + 6" + 1"
---For the 3-3.5cuft required, you can trade extra cabinet height for reduced cabinet depth.

A violin range is 196Hz to 2637Hz.... Typical Satori MW16P-4 crossovers are at 160Hz - 2,000Hz
 
Administrator
Joined 2004
Paid Member
While I can't answer the original question of which to choose, the 741 or the 761, I can say that I've never heard "small" speakers that do justice to classical music. Well once - at a show in Vegas I head a pair of slim towers that were marvelous on orchestral music.

Thus my love for large speakers, as classical makes up most of my listening. But not everyone has room for large speakers, either planar, open baffle or horn. So you use what you can fit on your listening space. I was happiest when I had a large space and large speakers. I listened to much more opera then. Small spaces and small speakers can do chamber music well, but nothing of a grander scale.

Have you considered, and do you have room for anything more large scale?
 
I have owned a great many speakers and am yet to work out what makes a good classical music speaker.I have the Kairos [both 2 and 3 way version] and do not think it is that good on classical.My Sonus Faber Cremona Auditor Ms were a lot better [especially for string tone].Some old B&W DM2s transmission lines were nearly very good as were some JBL Studio 590s and of course for orchestral music Bose 901s when set up properly can sound fantastic if a bit coloured and lacking in refinement.Then my Yamaha NS75Ts are superb on piano and the best speakers I have owned for that instrument.And yet all these speakers would appear to have nothing in common.So really speculating on what might sound good based on components or configuration is probably a waste of time.
If you want the best just buy a pair of Yamaha NS 5000s.The most real and convincing speakers I have ever heard for voice and acoustic instruments.

This is interesting feedback and shows a lot of this is to do with preference. I am only familiar with the Sonus Faber's (not the other speakers) and I prefer a more linear/cleaner mid-bass which is perceived as a thinner sound.

The NS-5000's do look awesome too!

I would really iterate, sort out room reflections and borrow a sub :)
 
Yes it is the small 3-Way that uses the 4" midrange
SBAcoustics-3WC
I'd like to hear those but do not know of anybody who has built them. Talking to others here my clone will be a sealed box plus a dedicated subwoofer as I too like deep and accurate bass

The SBAcoustics-3WC uses the SB line of drivers, whereas I want to go with Satori line. Not sure they are worth the extra money, but I'm willing to take that gamble. Don't want to do this twice.

I like the idea of going sealed, particularly since I plan to have separate subs. I'm assuming that I can seal the cabinet for the SBA 741 without any changes to the crossover. What do you think?
 
I learnt some lessons in my implementation. I built the Kairos with translam cabinets and made some mistakes. I'm looking at the best type of cabinets and may go constrained-layer-damping, as I feel the drivers and design deserve the best cabinet of my capability. I also don't like the physical appearance of the boxy bass bins.

The speakers themselves, the design is excellent:
Although, my previous speakers were ATC SCM100's, and I feel they're slightly behind on mid-range clarity (very slightly). Overall I prefer the Kairos to the ATC apart from the bass. I'm hoping a 4" mid-range driver will get me closer. I would also like to use the BE tweeter, but the Kairos would require significant cross-over changes and finally, I want less stressed bass.

I think the SB741 + 12" or two 10" actively driven side-firing would be best for my needs and importantly room size.

I would suggest, before you build anything. Look at room acoustics first and try to borrow a subwoofer. Jeff Bagby is an awesome designer and those piccolo's could probably get a bit further with bass reinforcing them and sorting out the room. I'd imagine the piccolos won't be miles behind the Satori designs.

Like you, I also like the idea that it is an open design.

Interesting that you really like the Kairos, even more than $20,000+ ATC SCM100s, while in the post right after yours jtgofish doesn't care much for them at all. Particularly for classical music. So, we need ask whether your comments are based on serious listening to classical music or to some other genre.
 
diyAudio Member
Joined 2007
I am going sealed with mine on the advice of more experienced members.
If my experience with the SB line of drivers is anything to go by the Satori line must be exceptional but at this time there is no 4" Satori only the 5"/130mm

My music tastes include some classical but more tone poems that symphonic and I also listen to a lot of female voice and jazz mixed with hard rock so my needs are very different to yours as is I think my budget so I can only offer an opinion based on limited knowledge. Also I must advise that I went B-Amp & Tri-Amp many years ago and that effects my own attempts at building speakers and I use cheap PA gear mixed with old 70's amps which do effect the sound.
Please take what I say with a grain of salt because I have definite bias to big speakers
 
If you want CLEAN-CLEAN-CLEAN sound, you need speakers which control directivity, or room treatment which controls reflections.

These two white papers from Dr. Earl Geddes explain the benefits of controlled directivity speakers in modest size home listening rooms.
http://www.gedlee.com/Papers/directivity.pdf
http://www.gedlee.com/Papers/Philosophy.pdf

-With a standard dome tweeter, take a second look at a sealed 12" + 6" + 1"
---For the 3-3.5cuft required, you can trade extra cabinet height for reduced cabinet depth.

A violin range is 196Hz to 2637Hz.... Typical Satori MW16P-4 crossovers are at 160Hz - 2,000Hz

Thanks for the suggestions about the Geddes papers. I perused them both, but frankly don't have the time right now to study them carefully. Trying to finish reading Toole's book first and that's no small task in itself.

I have no doubt that there will be many compromises in the sound quality achieved in my small room, which is far from ideal. It's small, almost square, and has glass windows completely filling one side. The opposite wall has wooden closet doors, so reflections will be different from the two long sides. Probably couldn't get much worse. The one possible good thing is very thick carpet on the floor.

I don't plan on doing any type of wall or window treatments. Those won't pass the WAF test. And not ready to try horns yet, either.

So while I do appreciate your suggestions and know you are right about many of the issues, I simply am going to have to accept whatever performance result I get from the room at this point. That said, I still want the starting point to be a speaker with the ability to deliver very good sound quality by itself.
 
Speaker subjective preferences are devious. You can't trust even your friends, it is so much in your head. I don't give any attention to loudspeaker reviews on magazines and web sites - I look at specs and measurements (box constuction, driver units, crossover points and topology, response, directivity, distortion, bass extension)

Listening room is always a problem. We can find many recommendations and rules for positioning in the web, many controversial to each other. I like speakers on the long wall quite close to it. The listening spot may not be too close to the back wall, in best scenario there should be lots of open space or dampening/diffusion like a bookshelf. If side walls are close (less than 1m) to speakers, early reflections make interferences, mess the tonality and imaging. Deep wave guides or horns are the only choice then, but they don't evoke so well the late delayed reflections that are good for the ambience that classical orchestral music deserves.

In a mid-size room speakers on the long wall, typical wide-dispersion 3-ways give their best, and so do dipoles. Panel speakers like Martin Logan Montis and dipoles like LX521 or my diy AINOgradient must have that wide room to work best!
 
I am going sealed with mine on the advice of more experienced members.
If my experience with the SB line of drivers is anything to go by the Satori line must be exceptional but at this time there is no 4" Satori only the 5"/130mm

You're right that the MR13P has an overall frame diameter of about 5", but Troels and others refer to it as a 4". It think that's because 4" is close to the actual diameter of the cone itself.
 
Thanks for the suggestions about the Geddes papers. I perused them both, but frankly don't have the time right now to study them carefully. Trying to finish reading Toole's book first and that's no small task in itself.

I have no doubt that there will be many compromises in the sound quality achieved in my small room, which is far from ideal. It's small, almost square, and has glass windows completely filling one side. The opposite wall has wooden closet doors, so reflections will be different from the two long sides. Probably couldn't get much worse. The one possible good thing is very thick carpet on the floor.

I don't plan on doing any type of wall or window treatments. Those won't pass the WAF test. And not ready to try horns yet, either.

So while I do appreciate your suggestions and know you are right about many of the issues, I simply am going to have to accept whatever performance result I get from the room at this point. That said, I still want the starting point to be a speaker with the ability to deliver very good sound quality by itself.

You don't need to go all the way to Geddes speakers to full fill controlled directivity they are like the pinnacle of CD designs. His goal is to give you as large a region of controlled directivity as possible and for that you need wide speakers and large diameter wave guides.

A DXT tweeter from SEAS is still a wave guide loaded tweeter and even with its small size gives a noticeable improvement in the 'focus' aspect of a tweeters sound vs the wider dispersion of naked domes. The DXT doesn't give you anywhere near as much range of controlled directivity but the benefit is still worth having in my opinion.

Then you get the smaller wave guide designs, using 5-6" wave guides. The Visaton WG 148 R and Monacor WG300 for example. Very room friendly and give you a considerable amount more of the good stuff vs what a DXT will do and a huge improvement over a naked dome.

You've also got coaxial drivers that, if well designed, do a similar thing. The tweeter using the cone of the coax as a wave guide and controlling the directivity as a result. KEF drivers are a great example of this as is the C18EN/MR18REX from SEAS. The coax drivers also coming with the added benefit of superb vertical and horizontal off axis performance.

I personally would never go back to naked domes for serious listening, or even casual listening if it can be helped.

Ignoring the lack of wave guides I don't like either of the Troels designs posted here. As usual he's used far too high of an xover point for absolutely optimal performance. If you want to go with Troels you could look into his 8008HMQ designs. Sensitivity and controlled directivity is bang on for realistic classical reproduction. Failing that seek other other designs using wave guides and at least incorporate them into your set of design choices. But if you have typically been let down by naked dome tweeter designs for giving you the presentation that you desire perhaps it is time to actually go for something different.
 
diyAudio Member
Joined 2007
You're right that the MR13P has an overall frame diameter of about 5", but Troels and others refer to it as a 4". It think that's because 4" is close to the actual diameter of the cone itself.

Fair enough, by that criteria my Vifa M11 is an 87mm driver as is the similar MCA12RC using 50% of the surround as part of the radiating area.
Nominal driver size does vary.
Looking forward to your build and your listening impressions
 
Administrator
Joined 2004
Paid Member
Yep, what 5th Element said. :up: Because you can't control the room, you'll need to take more care controlling the speakers. In the right space, even crappy speakers can sound OK (touring with a PA will quickly teach you that) but a poor room needs speakers that don't splash all over the place.

Thick carpet on the floor is good. If you can sneak some thick curtains onto those windows, all the better.
 
Interesting that you really like the Kairos, even more than $20,000+ ATC SCM100s, while in the post right after yours jtgofish doesn't care much for them at all. Particularly for classical music. So, we need ask whether your comments are based on serious listening to classical music or to some other genre.

Good point. I actually forgot to mention in my last post.

I listen to classical music and attend live classical music events but have a wide range of listening tastes. So I would take my comments with a pinch of salt.

I would also reiterate Juhazi. We all hear and want to hear different things. So subjective comments are hearsay really. Often you are also not aware of upstream components, the room etc - which can all have a substantial impact on someone's particular experience. Therefore I often look much closer at the objective capabilities and my room.

I appreciate the WAF of room treatment, but it can be done very nicely. Unfortunately, mine certainly isn't at the moment... So worth a look, to see if anything would be acceptable or sneak it into a "room redecoration" so everyone wins as its way more significant then changing speakers in my opinion.