SBA 741 vs. SBA 761 for Classical Music

I listen only to classical music and opera, and am looking at taking the next step up in speaker performance.

After trying a full range driver approach and realizing that they are not very good for classical music, I moved up to a pair of 2-ways with Jeff Bagby's Piccolos. That was a major improvement over the full range and now I'm finally enjoying the music. However, as good as the Piccolos are, they still don't give me quite the "big" sound that I am looking for with classical symphonies.

So now I'm researching the next step up, and believe that it has to be at least a 2.5 or 3-way. Troels Graveson has two new open SBA Satori designs that particularly interest me.

SBA-761

SBA-741

The SBA 761 is a 2.5 way and the SBA 741 is a full 3-way. Both use the TW29RN-B-4 for the tweeter and the MW19P-8 for the woofer. The difference is in the midrange and the cabinet design. The SBA 741 uses a 4" MR13P-8 for the midrange while the SBA 761 relies on the 6" MW16P-8 for that purpose.

I'm not going to ask which one is better, because that probably can't be answered. What I want to know, however, is what differences to expect in the sound.

Troels discusses the main differences on his website as follows:

With the 761 he says that by mating the MW16 and MW19, the latter gives quite a lot extra power in the lower registers. The combined membrane area is 277 cm^2. And that pays off in not only bass, but also upper-bass and lower midrange, which is a very important frequency range giving volume to grand piano and the cello.

The 741, on the other hand, uses a 4" driver for the midrange, which is much better at handling the upper midrange and lower treble compared to any 6 or 7" driver. The lower treble range he specifies to be ~800-1300 Hz while treble starts at 1280 Hz.

He adds that it comes as a surprise to some that 6" drivers are very often used to handle the treble, although it is very common in 2-way configurations in order to keep the cost down. However, this in a way contradicts the idea of the 761, essentially diminishing its value as an alternative to the 741.

What I am particularly interested in is any difference in the way the two will handle a sudden sharp string attack. When I listen to classical music and there is a sudden attack by the violins, for example, I want to hear a very, very sharp "kzing" and not a dull mushy "zuhm". This might have a lot to do with transient response and the cabinet themselves, so it may be difficult to predict.

Finally, I have two questions.

Which of these, the 741 or the 761, do you think will give me the better "kzing" on sharp violin attacks?

If you listen a lot to classical music, which would you choose? The 741 or the 761.

Thanks.
 
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For classical music it may be also worth looking out some of Paul Kittinger’s designs as he almost exclusively listens to classical music based on correspondences I have had with him. His designs are well regarded and often placed at the various shows. However many are MLTL floor standing designs. The CanTiLena is a good place to start but certainly not budget though (woofer is c£250) or the Cornetta which uses more affordable drivers.

Note, he does have a design stile which is not to everyone’s liking, I am sure all of his designs can be adapted to conventional boxes.
 
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Line source gave good advise. A floostanding 3-way can be your final speaker. From Troels SBA-10 is worth consideration, it has low tuned 10" bass. Most slim towers have too high br tuning, but that can be changed easily, or changed to sealed but then you need EQ.
 
A single (Sd=530cm^2) 12" woofer will generate the most coherent bass wavefront plus superior sealed-box transients to -F3=37Hz with SB34NRX75-6 in 3.5cuft.
 

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I appreciate all the responses, but most of them miss my main issue. I may not have made it as clear as possible, so here again is the question.

One of my primarily objectives is to hear a very sharp “kzing” and not a dull mushy “zuhm” sound from a strong sudden attack by 30 violins.

What’s not clear to me is whether this requires extra power in the bass, upper-bass, and lower midrange that Troels claims to be the main advantage of the SBA 761, or if it is more important to have the better handling of the upper midrange and lower treble he says is provided by the SBA 741.

Another objective, which I didn’t include in the previous post, is to hear music, violins solos in particular, that are so gorgeous musically that they can actually bring me to tears. I have experienced that previously with both recorded music and live concerts, and would like to have it be a part of whatever speakers I build next.

Juhazi gave me a specific answer and while I appreciate suggestions from others for speaker alternatives, I would first like to hear more opinions on which of these two designs from Troels, SBA 761 or SBA 741, would better meet my listening objectives.

“kzing” rather than “zuhm” and tears from Brahms Violin Concerto.

Again, thanks.
 
I've been working on almost exactly the above for my next 3 way. I got this far with a passive XO before trying my hand at active. May give you inspiration / hope.

NB: this was using the more sensitive MR16P midrange driver. The MW16P is probably sensitive enough, removing / reducing the padding resistor.
 

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I appreciate all the responses, but most of them miss my main issue. I may not have made it as clear as possible, so here again is the question.

One of my primarily objectives is to hear a very sharp “kzing” and not a dull mushy “zuhm” sound from a strong sudden attack by 30 violins.

What’s not clear to me is whether this requires extra power in the bass, upper-bass, and lower midrange that Troels claims to be the main advantage of the SBA 761, or if it is more important to have the better handling of the upper midrange and lower treble he says is provided by the SBA 741.

Another objective, which I didn’t include in the previous post, is to hear music, violins solos in particular, that are so gorgeous musically that they can actually bring me to tears. I have experienced that previously with both recorded music and live concerts, and would like to have it be a part of whatever speakers I build next.

Juhazi gave me a specific answer and while I appreciate suggestions from others for speaker alternatives, I would first like to hear more opinions on which of these two designs from Troels, SBA 761 or SBA 741, would better meet my listening objectives.

“kzing” rather than “zuhm” and tears from Brahms Violin Concerto.

Again, thanks.

Have you emailed Troels? He would be best placed to answer. I'm sure he'd like to help you choose which of his designs might give you want you are after considering he also appreciates classical.
 
classicalfan, did you notice that Troels shows a bass module designed for the 741?

A good hifi speaker will never sound zuhm,unless it is on the recording, no matter how low the speaker can go. The realism of classical recordings gets much better if the speaker can easily go to 30Hz, without blowing it through the reflex pipe. I was never happy with 2-way plus subwoofer, but a 3-way with capable bass made feel like I was at concert! I was surprised how important it is and it doesn't fight with good treble.

Commercial speakers that can go low without a subwoofer are rare, but the floorstanding B&W speakers do that. They have wobbly treble with sharp highs, but go to a hifi shop and listen to the bass!

You don't have to do like Linesource and I say, but a single 7" tuned around 38Hz is not hifi to us. Be warned!
 
I have 10" sealed bass drivers and they need assistance in my room from a subwoofer - especially on some full orchestra pieces.

Take a look at:
Tech Stuff - Frequency Ranges

There are quite a few instruments below 50Hz as their lowest fundamental.

I've never been happy relying on room gain to make up the bottom end of a speaker. I'm a believer you need a large cone area (>= 12") for modest listening rooms (mine being 7m * 5.5m * pitched 4m ceiling) to get adequate non-stressed bass.

Hence my desire for a 12" 3 way TMW speaker.
 
One of my primarily objectives is to hear a very sharp “kzing” and not a dull mushy “zuhm” sound from a strong sudden attack by 30 violins.

“kzing” rather than “zuhm” and tears from Brahms Violin Concerto.

CONTROLLED DIRECTIVITY
The controlled directivity from a horn loaded tweeter will provide both the dynamics and the "crisp direct sound" you seek. A standard dome tweeter spreads the high frequencies around the room, generating reflections which smear the sound as they bounce off the walls and ceiling/floor. "zzzzuhm" instead of "Kzing"
=======

"Open Source Tower XL" Goals : amp friendly (high efficiency) and flattish impedance curve of 8 ohms, low bass extension of 35Hz within -3db and cabinet volume will be up to 150 liter. Drivers costs will be maximum of 1000$ for the pair ( excluding crossover parts and cabinet)."

I believe the goals in this open 3-way Focal driver design thread will satisfy your requirements... You just have to get a little horny to get controlled directivity. There are other 3-way horn designs with great reviews you can study.

Open Source "Tower XL"

1" compression driver and tweeter horn
8" midrange
15" ported woofer
 
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.
 
classicalfan, did you notice that Troels shows a bass module designed for the 741?

A good hifi speaker will never sound zuhm,unless it is on the recording, no matter how low the speaker can go. The realism of classical recordings gets much better if the speaker can easily go to 30Hz, without blowing it through the reflex pipe. I was never happy with 2-way plus subwoofer, but a 3-way with capable bass made feel like I was at concert! I was surprised how important it is and it doesn't fight with good treble.

Commercial speakers that can go low without a subwoofer are rare, but the floorstanding B&W speakers do that. They have wobbly treble with sharp highs, but go to a hifi shop and listen to the bass!

You don't have to do like Linesource and I say, but a single 7" tuned around 38Hz is not hifi to us. Be warned!
Yes, I agree with this. Should have mentioned before that I plan to later add an active subwoofer to the system. My initial concern is with the midrange and that's what I'm trying to nail down first.
 
I have 10" sealed bass drivers and they need assistance in my room from a subwoofer - especially on some full orchestra pieces.

Take a look at:
Tech Stuff - Frequency Ranges

There are quite a few instruments below 50Hz as their lowest fundamental.

I've never been happy relying on room gain to make up the bottom end of a speaker. I'm a believer you need a large cone area (>= 12") for modest listening rooms (mine being 7m * 5.5m * pitched 4m ceiling) to get adequate non-stressed bass.

Hence my desire for a 12" 3 way TMW speaker.

No argument about the need for a subwoofer and my plan is to add one or two of them in separate cabinets. But I really want the basic TMW cabinet width to be no more than 12". A little less would be better.

Troels SBA 941 is still another possibility that I didn't discuss before, because it's not an open design like the newer 741 and 761.
 
diyAudio Member
Joined 2007
I've been reading Troels pages a lot lately while thinking about my next 3-Way project. Read what he says about the fast attack of a good 4" midrange and imagine his smaller 3-Way projects with a really good 12" bass driver
" The MCA12 is a darling. What you immediately recognise from this construction is the unusual wide dispersion of the midrange. If you're used to listening to 2-ways with a 6-7" midbass, the sound from the 3W Classic will be very much different. Besides the midrange dispersion, the MCA12 is fast as lightning and you will get a transients attack not possible from 15 grams 6" cones. The 4" middriver may be one of the clues to "an easy to listen to" speaker"
SEAS-3-Way-Classic
SEAS-3-Way-Classic-mkII
Of all the old school Vifa drivers in my stash I prefer the M11-MH, it is very similar to the MCA 12RC, so much so that I could probably use the Troels design with my existing Vifa drivers
 
I've been reading Troels pages a lot lately while thinking about my next 3-Way project. Read what he says about the fast attack of a good 4" midrange and imagine his smaller 3-Way projects with a really good 12" bass driver
" The MCA12 is a darling. What you immediately recognise from this construction is the unusual wide dispersion of the midrange. If you're used to listening to 2-ways with a 6-7" midbass, the sound from the 3W Classic will be very much different. Besides the midrange dispersion, the MCA12 is fast as lightning and you will get a transients attack not possible from 15 grams 6" cones. The 4" middriver may be one of the clues to "an easy to listen to" speaker"
SEAS-3-Way-Classic
SEAS-3-Way-Classic-mkII
Of all the old school Vifa drivers in my stash I prefer the M11-MH, it is very similar to the MCA 12RC, so much so that I could probably use the Troels design with my existing Vifa drivers
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.