Bohlender-Graebener Z1 vs Infinity Kappa 5.1

Just got a new pair of BG Corporation Z1 small bookshelves yesterday, to replace my damaged Infinity Kappa 5.1 Series II bookshelves (very big, almost like floorstanding).

I think this provides for an interesting review/comparison between them, since both speakers share some similar design characteristics (magnetic planar tweeters mated with conventional cone drivers) yet also have some significant differences (2-way vs 3-way design, different crossover points, different material cone drivers).

I've already done some listening tests on the Z1s though they still need more time to break in. I can hear many major differences in the way they sound compared to my Kappas.

I'm not that experienced in audio matters though so I don't know how well I can analyze the differences. I thought maybe first I'd ask some questions.

On average, do 3-way speakers tend to sound different from 2-way speakers? What are the advantages and disadvantages of 3-way designs?

If anyone else owns Infinity Kappa 5.1 Series II speakers I'd like to hear your thoughts on how they sound. To me, they sound like the weirdest speakers I have ever heard, in terms of their tonal balance. I think it is because their midrange is tuned very loud relative to their other frequencies. I wonder if this is because of them being a 3-way design, but other 3-way designs I've heard don't sound as weird as the Kappa 5.1s. I'm not sure what causes them to have the tonal/timbre characteristics that they do, does anyone else have any experience with these?

The BG Z1s sound more like normal speakers I would say. Both the Z1s and the Kappas have the excellent 3 kHz - 20 kHz response I would expect out of ribbon tweeters, but below 3 kHz they don't sound the same at all. With the BGs all I can hear are the sharp and tinky high frequency sounds (I listen to mostly synthetic techno/pop music) and powerful bass notes...I can barely hear the main singer's voice (usually, a high-pitched girl voice). With the Kappas the singer tends to be by far the loudest thing playing.

I've also got a pair of BG Z7s towers on the way too, but I expect they will sound similar to the Z1s. They have the same 2-way design and components, only with 2 woofers instead of 1.

.....here we go again....cross-wire your BG's, and see if the vocals suddenly become more acceptable....my four speakers sound better wired normally, but it was close....I'm convinced some speakers out there should be crossed and left that way, and the use of subs will uphold the effort.....

.....the most difficult area to resolve in a speaker enclosure is the highs as per my experience....when cross-wiring, I found it necessary to cut the signal to my speakers at about 10K, because the highs were made twice-efficient also and a degree of raspiness crept in....you may not need to have a high cut, I don't know....your amp section will run cooler, and if the speaker blows up, Buck will buy it, haha....some will say you will lose bass....wrong, you will lose any mud concerning the lows....and you've got your subs to keep you warm....I found cross-wiring my speakers made me very content with lower listening levels because I could hear everything at lower levels....hello WAF......

.....I'm serious....but you may get 200 private messages in the next 10 minutes saying mule is nuts....go with your gut, haha.....

.....Porcupine, I gots to post one more and say the "here we go again" does not relate to you or your outstanding post in any way.....

I'd say give the B&G's some time to break in. I've heard neither speaker, but The Absolute Sound rated the B&G's "Budget Loudspeaker of the Year". So they must be do something right. It's just odd to me you went with the same type of speaker, driver/configuration wise. Since you like ribbon/cone hybrids, check out the new aluminum Elac's and even more so the new Eben X-centrics....sick. Happy listening.

mule, what do you mean by cross-wire? Do you mean purposefully swap the positive-negative wires to one speaker to invert its phase?

Lagger, yup after about 20 hours of break-in my Z1's sound far better. The initial harshness and listening fatigue is mostly gone away now as I expected. Also even the midrange and thus the (female) singer's voices seem louder (in general, half of their voice comes from the tweeter, but their fundamental lowest frequency is usually in the 1kHz to 2kHz range I think). They still don't sound anything like the Kappa 5.1s, but that's more due to the 5.1's being colored with abnormally loud midranges, than the Z1's lacking midrange response.

I had already expected this type of sound before I got my Z1's so it is of no surprise to me and I do not really mind it, but I do sort of like the colored way the Kappa 5.1 sounds.

Thanks for the reference to Elac, Eben speakers. I took a look at them online just now. The Ebens don't impress me (they aren't worth $5000 a speaker). The various ribbon Elacs though look very interesting. Cost range (~$1000-$3000 a pair it seems like) seems to be about the same as Aurum Cantus ribbon hybrids, and performance seems similar as well. I was also considering Aurum Cantus (had auditioned them) but decided to go with cheap Bohlender-Graebener stuff....$400 for a pair of Z1s, and $800 for a pair of Z7s.

I would have bought Infinity again but they no longer make ribbon hybrid home speakers.

My ideal speaker though would be VERY odd. As I get older and hear more types of speakers I get a better sense of what I prefer to listen to.

Maybe you could give me suggestions on if any speakers exist that better fit my preferences?

1) I hate low-frequency sounds. In fact I prefer it if my speaker cuts or rolls off all frequencies below 100 Hz. Maybe even 200 Hz. When I listen to music I usually turn the bass control on my receiver down as far as it goes. I realized how much I hate bass when I found I still do this even for my B&G Z1s. They have far too much bass for me and it hurts my head and ears. Their bass response though is excellent, tight, deep, clean, not too loud, and fairly free of resonance (and I believe I have located them in my room reasonably well). They have some of the best controlled bass I've ever heard in any speaker, not too boomy like many other speakers are, with smooth roll-off around 55 Hz. Yet, even with what I'd consider perfect bass, I prefer it to be equalized down. Stuff below 60 Hz I probably want to equalize down to -12 db, and stuff below 200 Hz I probably want equalized down to -6 db or so.

2) I love high-frequency sounds. Although absolutely nothing comes out of my playing devices above 17 to 20 kHz due to source sampling rate and DAC converter filter, the sounds I consider most noticeable and pleasant to listen to are in the 10 kHz to 20 kHz range. I have yet to hear DVD audio unfortunately (I'm a caveman!) but when that becomes standard I'll probably be a very happy person (the type of music I prefer to is Japanese anime music, pop/techno music, or videogame music...which have the loudest high-freq sounds of any genre, but are probably backwater and will be the last to convert to DVD audio). Anyways, so my #1 criterion for speakers is high-freq response. I look for upper-freq bandwidth of 30 kHz or more, which is usually only quoted by ribbon or mag planar tweeters. So that's why I keep buying ribbon/cone hybrids.

If possible I always want to see white paper frequency response curves for tweeters. The reason I did not buy Aurum Cantus was that their tweeter freq response white paper revealed -4 db response dips in the whole 15 kHz to 20 kHz range which is the most important range to me. Their tweeter is still -3 db or something at 40 kHz which is awesome, but the response dip in the 15 kHz range looked unacceptable to me.

I also think ribbon tweeters are good cause I think they have the best transient response of anything. Though metal domes are good too; I don't think I'm dead-set on ribbon tweeters.

I've also been very interested in the long, pure magnetic planar designs. Like Magnepans, B&G Radia series, etc. The thing with these though is that I noticed they have bad high-freq response. They struggle near 20 kHz and by then have rapidly decreasing freq response.

So I guess my ideal speaker is a 2-way system with one long magnetic planar midrange/tweeter driver, essentially mated to a supertweeter. I also read that low-pass crossovers horribly limit pulse risetime, maybe this is why I've never enjoyed listening to the sounds of anything coming from any driver other than a tweeter, in any speaker. So I'd probably want to cross my ribbon tweeter at 10 kHz or so with a high-pass filter. And I'd probably just want to leave my midrange ribbon totally uncrossed, for full-range response to 20 kHz...that way transient response wouldn't be lost. And hopefully attune the supertweeter's high-pass attenuation so that when superimposed upon the midrange ribbon it gives a flat response from 10 kHz on up. Or even if the sound ended up at +6 db or whatever I probably still wouldn't mind.

I've never heard a full-ribbon speaker before unfortunately. I don't think any local stores have any that I can listen to. I have no idea if what I imagine is really what I want, but ohwell.

Maybe what I want already exists? B&G Corporation Radia 220i seems to roughly fit what I described. Except they cross the Neo8 midrange ribbon to the Neo3PDR ribbon at a normal 2500 Hz. So probably it is a standard design where the Neo8 has a lowpass filter on it, which I didn't want. I dunno, I wish I could find all these speakers and listen to what they sound like so I can figure out (or make) what I really want.

Magnepan has a bunch of interesting stuff but their website is filled with only propaganda, with zero specifications/papers, so I distrust them.

"They struggle near 20 kHz and by then have rapidly decreasing freq response"

.....Porcupine, you said in one post, "as I get older", and then you post the above....do you really hear that high of frequencies?.....

.....I definitely applaud your preference of 2-way speakers, btw.....

Well, I am getting older so yeah my high freq response is probably going down. But I'm still only 27 so I'm still pretty sensitive. Probably had ultrasonic dog hearing when I was born.

In general I don't know if I like 2-way or 3-way speakers more. I'm still in the process of learning much more about hifi audio.

Just learned that what I described is sometimes called a 1 1/2-way speaker. N 1/2-way speakers aren't that common though but there are some out there. I would love it if a company would actually make a good speaker exactly like what I described; I think it'd be awesome.

.....27, huh?....Porcupine, we're sensitive guys, and our heart goes out to you in your struggles....stiff upper lip, young man, it could get worse.....

.....you guys who have made imaging/point a measuring stick for the all-important "live presence" through your experience, which type of speaker stands the best chance for drop-dead imaging, and the elements of the speaker, speaking, as one voice?....2-way or 3-way?.....

Porcupine said:

Well, I am getting older so yeah my high freq response is probably going down. But I'm still only 27 so I'm still pretty sensitive. Probably had ultrasonic dog hearing when I was born.

Click to expand...

You must be somekind of hybrid human being...

You say: "I look for upper-freq bandwidth of 30 kHz or more, which is usually only quoted by ribbon or mag planar tweeters. So that's why I keep buying ribbon/cone hybrids."

Species Approximate Range (Hz)
human 64-23,000
dog 67-45,000
cat 45-64,000
cow 23-35,000
horse 55-33,500
sheep 100-30,000
rabbit 360-42,000
rat 200-76,000
mouse 1,000-91,000
gerbil 100-60,000
guinea pig 54-50,000
hedgehog 250-45,000
raccoon 100-40,000
ferret 16-44,000
opossum 500-64,000
chinchilla 90-22,800
bat 2,000-110,000
beluga whale 1,000-123,000
elephant 16-12,000
porpoise 75-150,000
goldfish 20-3,000
catfish 50-4,000
tuna 50-1,100
bullfrog 100-3,000
tree frog 50-4,000
canary 250-8,000
parakeet 200-8,500
cockatiel 250-8,000
owl 200-12,000
chicken 125-2,000

link: http://www.lsu.edu/deafness/HearingRange.html

My goldfish can hear to 3500Hz.


Chinchilla 90-22,800 They just had to keep going to get that extra 800, didn't they?

I'm glad the B&G's are working out for you. You should probably give them another 30 hours before you start making any judgements. I can't believe you dont think the Eben's are worth it! They're a new company and make their ribbon tweeter in-house. The drivers are designed by the gentleman who started Scanspeak and Dynaudio (which I own), and they're internally wired with Nordost monofilament. Now thats sweet! But out of my price range as well Although they sure beat Burmester's new statement ribbon/cone hybrid speaker ($100k)

Something I have heard and do suggest are 'Red Rose' speakers made by Mark Levinson (when it was still Mark Levinson). Wow, what wonderful integration between the Dynaudio driver and the ribbon tweeter they had! A very neutral speaker, truly something special. You can find them used around $2k ballpark. A great great standmount. Happy listening.

Porcupine said:

mule, what do you mean by cross-wire? Do you mean purposefully swap the positive-negative wires to one speaker to invert its phase?

Lagger, yup after about 20 hours of break-in my Z1's sound far better. The initial harshness and listening fatigue is mostly gone away now as I expected. Also even the midrange and thus the (female) singer's voices seem louder (in general, half of their voice comes from the tweeter, but their fundamental lowest frequency is usually in the 1kHz to 2kHz range I think). They still don't sound anything like the Kappa 5.1s, but that's more due to the 5.1's being colored with abnormally loud midranges, than the Z1's lacking midrange response.

I had already expected this type of sound before I got my Z1's so it is of no surprise to me and I do not really mind it, but I do sort of like the colored way the Kappa 5.1 sounds.

Thanks for the reference to Elac, Eben speakers. I took a look at them online just now. The Ebens don't impress me (they aren't worth $5000 a speaker). The various ribbon Elacs though look very interesting. Cost range (~$1000-$3000 a pair it seems like) seems to be about the same as Aurum Cantus ribbon hybrids, and performance seems similar as well. I was also considering Aurum Cantus (had auditioned them) but decided to go with cheap Bohlender-Graebener stuff....$400 for a pair of Z1s, and $800 for a pair of Z7s.

I would have bought Infinity again but they no longer make ribbon hybrid home speakers.

Click to expand...

Dude, look what I found.......

http://cls.audiogon.com/cgi-bin/cls.pl?spkrmoni&1123969667

peace...

VMPS is another good option, check out this. I dunno about anyone else, but i honestly think that VMPS speakers have the ugliest drivers I've ever seen. Not sexy in the least.

mulester, I meant that my *ears* are still sensitive. I think maybe you misinterpreted my sentence lol.

jax, wow VMPS looks awesome! Their QSO 626 Ribbon and Ribbon Monitor 1 are exactly what I described/imagined!! Ribbon mids crossed to Ribbon supertweeters at 10 kHz. And the price is very affordable at $800 a speaker. You are right their designs look totally crude and ugly but they seem to be the type of speaker designers that are more enthusiasts than businessmen so they probably don't specialize in their looks hehe.

Some of their bigger designs are even more crazy. A lot of them have 2 or 3 Ribbon tweeters hehe.

I wonder if their Ribbon mids are sent through a low-pass crossover? I've been scouring their webpage but haven't really been able to find out. If not, then they'd truly be my ideal speaker.

It bothers me that they don't put frequency response (such as 40 Hz to 30 kHz, +/-3 dB) specifications on their page. Is it because they think it is beneath them to put such basic info, or because their speakers don't comply or they don't know?

That's an awesome reference though jax, thanks a lot!!

> human 64-23,000

Huh? If that is to be believed, why should we care if our speakers are responding below 64 Hz? If we still think down to 20 Hz is necessary, then we should believe up 70000 Hz is as well, by the same arguments.

In any case, even though I look for speakers with good freq response at 30 kHz or more, that doesn't mean that I think I can hear well at 30 kHz (maybe I can, maybe I can't, I currently have no scientific way to test myself to find out). But when speakers respond well at 30 kHz that suggests that they likely respond strongly, and respond flat, in the 15 kHz to 20 kHz range which everyone accepts is audible, and which to me is the most critically important response range.

That being said, I still much prefer to look at tweeter white papers when I can find them. The G2si and G3si white papers were what made me reject Aurum Cantus. But I have a high opinion and respect for any company that makes their research white papers public to everyone to be scrutinized. A lot of Bohlender-Graebener white papers can be found online and that's what made me decide their speakers could be trusted.

> presumably lower frequencies could have been detected if a loud enough stimulus was used, and likewise for high frequencies.

That quote comes from the link mfabien provided. This supports what I've always thought (and said in the beginner's forum here in a different thread)...some humans CAN hear frequencies much higher than 20 kHz. If that data is correct, human hearing range is approximately either 64 Hz - 23000 Hz, OR probably roughly 20 Hz - 70000 Hz. It just depends on what you define as your hearing limit (in terms of how loud the source stimulus is).

I suspect that the "result" 20 Hz - 20000 Hz quoted by many computer programmers, audio encoding format engineers, hardware engineers, speaker designers, etc is some totally made-up myth that has somehow become standard because that is what people *wish* were the truth. Especially the people who designed the formats for CD audio, etc...they don't want people to know the truth.

Play any sound loud enough and I think we will hear it even at supersonic frequencies. Essentially that is what we are doing with our bass instrumentation to begin with. Why is it that in music, the bass amplitudes and power output is 10x or 100x more than the midranges/treble amplitudes? It's because humans are so unsensitive to frequencies below 100 Hz that we need SPL levels 10x greater to perceive sound. To me that's unnatural, and that's why I prefer to listen to music with everything below 100 Hz filtered out. It's only fair in my mind that we treat the high and low end of the audio spectrum with equal fairness. If we aren't gonna have 500-watts coming out of our supertweeters at 40 kHz so that we can hear it, why should we have 500-watts coming out of our subwoofers at 20 Hz just so we can hear it?

Ah, no prob. I'm sure you can shoot them an email regarding frequency response. I know in their paragraphs of literature they post specs on their tweeters (not the whole speaker). If I remember correctly, the spiral ribbon tweeter is flat to 25kHz. The speakers that I linked to (the 626 series) have their -3dB point at 42Hz. The designs are 2 and 3 way. The QSO626 is a bass-reflex D'Appolito design that is a 2-way speaker. The QSO626SE is an upgraded version with better drivers. the QSO 626 Ribbon is a 3-way design with a cone, midbass, a ribbon midrange, and a tweeter up top. Good Luck your search.

"But when speakers respond well at 30 kHz that suggests that they likely respond strongly, and respond flat, in the 15 kHz to 20 kHz range which everyone accepts is audible, and which to me is the most critically important response range"

.....now this is my kind of cognitive reasoning....I agree this type of overkill is good.....