Should I Just Give Up on These Speakers?

[fineMen]

... all at different heights, and 4-5 of those drivers emitting sound at highly directional frequencies, ...
That said, whether I took 3, 5, 9, or 13 measurements with Dirac, the frequency response graphs didn't vary a whole lot.

I don't know what Dirac actually measures, sorry. But again, a DIYer, of today as I shall say, could possibly help out with getting the most informative data on that impressive speakers in situ. Especially including singled-out at the crossover for a pair or three drivers alone. I argue that the original wasn't as as sensibly designed back then as we now expect for post-spinorama era. I'm afraid speculations won't help you.

 

[tmtomh]

I don't know what Dirac actually measures, sorry. But again, a DIYer, of today as I shall say, could possibly help out with getting the most informative data on that impressive speakers in situ. Especially including singled-out at the crossover for a pair or three drivers alone. I argue that the original wasn't as as sensibly designed back then as we now expect for post-spinorama era. I'm afraid speculations won't help you.

Yes, a DIYer could remove the binding post panel and probably isolate parts of the crossover network, or individual drivers, to measure them. And yes, that's beyond what I feel comfortable doing, and beyond what I would want to do. The speakers can be bi-amped, but that only isolates the two woofers from the other 5 drivers, so not of much use given that the crossover, frequency-response, and directivity questions are in the mids and highs.

Of course there will be no spin data for these, but I have been surprised that I've been unable to find even gated measurements above 200-300Hz, from either an audio magazine back in the day, or a DIYer more recently. In fact, I suppose I could do it myself using my UMIK mic and REW.

 

[Roland68]

Hello all,

As noted in another thread, I recently inherited a pair of Infinity Kappa 9 speakers, in excellent shape with replaced woofer surrounds and a drop-in replacement for the original polydome midrange. They are excellent speakers in some respects, but I am having a very difficult time trying to dial in their in-room frequency response - and I am getting extremely frustrated trying to use Dirac with a MiniDSP SHD to achieve proper response.

I've taken several sets of measurements, using 9 or 13 measurements as Dirac recommends, and also using fewer measurements as some folks here recommend. I've tried using Dirac correction only from 300Hz down, as some advise, and also using it full-range, as others here say they've done successfully. I've also tried in-between corrections, up to 700Hz and up to 4kHz.

Finally, I've tried using several different target curves: Dirac's new default, which appears to be a Harmen/Toole-esque curve with about 8dB bass boost at 20Hz and sloping to about -0.5dB at 20khz. I've also tried the so-called "Harman curves" that are floating around online (I know there's not really a Harman curve), with 6dB and 10dB boost at 20Hz, and I've tried tapering to -1.5dB, -3dB, and -6dB at 20kHz (while keeping the curve linear until about 2.5kHz).

With that said, here is what Dirac shows as the response from 13 measurements (top image) and from another, separate round of 7 measurements (bottom image). To be clear, these are the pre-correction responses.

View attachment 295978

View attachment 295979

Note not only the nonlinear response, but also that the scale is 10dB per vertical unit. According to Dirac, there's an 8dB dip at 5kHz compared to about 2.5Khz and about 7kHz. There's also about 4-5dB of nonlinearity at various points from the Schroeder frequency up to 1kHz.

This just seems awful - or am I expecting too much from a non-smoothed response graph of passive speakers with no built-in DSP?

Now, the speakers don't actually sound to me the way this curve suggests. But they don't necessarily sound quite right either. I don't even know exactly what Dirac is showing me here - is this an average of in-room response from all the measurements? Or has Dirac used those multiple measurements to calculate a quasi-gated or quasi-anechoic response curve for the speakers here? If I'm not supposed to use Dirac to flatten the response above about 300Hz, and I can't use these Dirac measurements as indicators of what my ears are actually hearing in-room, then how am I supposed to use PEQ to try to flatten the response?

Should I just give up and sell these speakers and get an active speaker with built-in DSP instead? I feel like I'm caught in a classic circle of confusion, no longer being able to tell with confidence if the tonality of my music is right or not, and seemingly having no dependable way to know how I should actually be EQ'ing these speakers above 300Hz for decently accurate response. I mean, can we simply not own speakers if they are too old to have spinorama data available?

As might be obvious from this post, I'm kind of at the end of my rope at this point. I feel I've tried my best here and I'm most definitely not having fun anymore at this point. I would be grateful for any perspective, guidance, advice, or helpful thoughts anyone can provide, to help me better understand what I'm looking at here and perhaps how I might come to an informed decision about continuing to work with these speakers versus giving up.

Thanks!

At least 6-7 electrolytic capacitors are installed in the crossover, which could cause problems after more than 30 years and then have much lower capacities (or none at all). Especially if the speakers have not been used for a long time. This is also indicated by your measurements.
Capacitor gauges can be had for under $20. But it is best to replace all electrolytic capacitors with film capacitors with the same values (imprint) and at least 160V (or more). MKTs are now very cheap, MKPs affordable.

 

[Mart68]

Shortly after my last previous post in this thread, I felt I was finally getting them closer to dialed in. But I also realized that it’s not just about figuring out the sound. It’s also about how one feels looking at fairly large (albeit svelte looking in this case) speakers all the time when listening; about how much one likes vintage gear, complexity, tinkering/experimenting, and so on. In my particular case, there’s the added factor that these were my father’s, who passed recently. Recently I have realized that my experience of packing these up, hauling them into my room, setting them up, learning Dirac to smooth the in-room response, and so on has been all tied up with the grieving process. I have many items of his in my space now, and they are cherished reminders, but at the end of the day I realized that something about having those two very large reminders of him in my room (and not his room where I’d experienced them for so long) just made me sad.

Sorry to go on, but I just wanted to explain why I think these speakers are so cool, but ultimately not for me. I have replaced them with actives and am quite happy so far. I am planning to sell the Kappas before the end of summer, but it will have to be to a local buyer for obvious reasons.

Sorry about your father, I speak from personal experience when I say that particular loss is the hardest thing in the world to go though.

Maybe consider putting them in storage? It will take a long time before it gets to the point where thinking of him makes you happy rather than sad, but you will get there. At that point you might regret having moved them on.

Anyway you have to do what is best for you, it's just a suggestion.

 

[mhardy6647]

I'm lucky I don''t have a car. If I did my house would be full of speakers, there's always some for sale that I am interested in, just too far away.

You're even luckier that you don't have a truck.

 

[tmtomh]

Sorry about your father, I speak from personal experience when I say that particular loss is the hardest thing in the world to go though.

Maybe consider putting them in storage? It will take a long time before it gets to the point where thinking of him makes you happy rather than sad, but you will get there. At that point you might regret having moved them on.

Anyway you have to do what is best for you, it's just a suggestion.

Thanks for your kind words, and yes - without wanting to go too far afield of the thread title and our discussions in general here at ASR, it's a difficul loss not only in and of itself, but also because he was my last living parent.

At any rate, @Roland68 makes an excellent point about the capacitors (and possibly other components?) in the crossover networks. I don't believe the speakers have ever sat unused for long. My father listened to them regularly, and the time gap from when he last used them to when I got them set up in my room was 3 months or less (and in that time I played them on two occasions when I was at his house clearing things out, so they didn't totally sit during that time either). Also, in my experience 34 years is sort of 50-50 for capacitors - some definitely need replacing, while others can last for 40-50 years no problem.

At any rate, @Mart68 , I really like your suggestion. I am fortunate that, at least at this time, I do not need the money from selling the Kappas in order to make ends meet in the day-to-day, and you're right that in the fullness of time I might decide I want to have them around. (Fortunately my listening room and our storage area are on the same floor, and I have dollies that enable me to move them in and out by myself). I'll wait and see for a while, and maybe I'll find a tech or DIY'er with specific experience with Kappas who would be interested in being paid to refurbish those crossovers.

In the meantime, I'm quite happy with my new setup (which was my next planned step before the situation with my father arose), so I am grateful that I can take some time to decide.

And having another setup that suits me as my primary stereo also makes me much less risk-averse when it comes to learning how to remove the crossovers myself, getting them worked on, and so on. It's a lot less nerve-wracking to do all that stuff when it's not your only listening option!

 

[Bird_of_Hermes]

In case anyone wants to see the “fun” impedance/phase charts for the Kappa 9.

And another:

Kappa 9.2s and 8.2s impedance plots here as well.

That 7kHz point is pretty nasty too. 1.5 ohm with a 45 degree phase angle.

 

[tmtomh]

Yes, although that's with the bass switch in Extended mode. In Normal it's about a 4 ohm load in that 30-35Hz area.

 

[Bird_of_Hermes]

The top graph indicates that isn’t the case (it has both), but it did come from someone that’s been moding their speaker, so *shrug*.

Rot = red

Infinity 8 Kappa Rescue Project

I did repair the original polydomes using a 3" doped paper dust cap and they worked well, but I have no idea how they compare to unspoiled polydomes. The TBs are the best so far and with my minidsp I can readily correct anomalies in FR, but strangely the little bamboo drivers blend right in with...

www.diyaudio.com

 

[tmtomh]

The top graph indicates that isn’t the case (it has both), but it did come from someone that’s been moding their speaker, so *shrug*.

Rot = red

Infinity 8 Kappa Rescue Project

I did repair the original polydomes using a 3" doped paper dust cap and they worked well, but I have no idea how they compare to unspoiled polydomes. The TBs are the best so far and with my minidsp I can readily correct anomalies in FR, but strangely the little bamboo drivers blend right in with...

www.diyaudio.com

Ah, good point! Well, I guess 1.5 ohms is better than 0.8 ohms.

At any rate, I didn't experience any problems driving them in either mode.

 

[Bird_of_Hermes]

Ah, good point! Well, I guess 1.5 ohms is better than 0.8 ohms.

At any rate, I didn't experience any problems driving them in either mode.

That is really interesting to me because I would expect that you would have issues.

Normally a 45 degree phase angle requires the amp to dissipate 2x the power (heat) it normally does (the speaker isn’t really impacted by this), so a 1.5 ohm impedance with that phase angle requires an absolutely catastrophic amount of thermal dissipation at even moderate amounts of power.

Class D, while very energy efficient, is quite weak in this aspect, most designs are poorly heat sinked on both the amp and the PSU.

 

[Philbo King]

F

Hello all,

As noted in another thread, I recently inherited a pair of Infinity Kappa 9 speakers, in excellent shape with replaced woofer surrounds and a drop-in replacement for the original polydome midrange. They are excellent speakers in some respects, but I am having a very difficult time trying to dial in their in-room frequency response - and I am getting extremely frustrated trying to use Dirac with a MiniDSP SHD to achieve proper response.

I've taken several sets of measurements, using 9 or 13 measurements as Dirac recommends, and also using fewer measurements as some folks here recommend. I've tried using Dirac correction only from 300Hz down, as some advise, and also using it full-range, as others here say they've done successfully. I've also tried in-between corrections, up to 700Hz and up to 4kHz.

Finally, I've tried using several different target curves: Dirac's new default, which appears to be a Harmen/Toole-esque curve with about 8dB bass boost at 20Hz and sloping to about -0.5dB at 20khz. I've also tried the so-called "Harman curves" that are floating around online (I know there's not really a Harman curve), with 6dB and 10dB boost at 20Hz, and I've tried tapering to -1.5dB, -3dB, and -6dB at 20kHz (while keeping the curve linear until about 2.5kHz).

With that said, here is what Dirac shows as the response from 13 measurements (top image) and from another, separate round of 7 measurements (bottom image). To be clear, these are the pre-correction responses.

View attachment 295978

View attachment 295979

Note not only the nonlinear response, but also that the scale is 10dB per vertical unit. According to Dirac, there's an 8dB dip at 5kHz compared to about 2.5Khz and about 7kHz. There's also about 4-5dB of nonlinearity at various points from the Schroeder frequency up to 1kHz.

This just seems awful - or am I expecting too much from a non-smoothed response graph of passive speakers with no built-in DSP?

Now, the speakers don't actually sound to me the way this curve suggests. But they don't necessarily sound quite right either. I don't even know exactly what Dirac is showing me here - is this an average of in-room response from all the measurements? Or has Dirac used those multiple measurements to calculate a quasi-gated or quasi-anechoic response curve for the speakers here? If I'm not supposed to use Dirac to flatten the response above about 300Hz, and I can't use these Dirac measurements as indicators of what my ears are actually hearing in-room, then how am I supposed to use PEQ to try to flatten the response?

Should I just give up and sell these speakers and get an active speaker with built-in DSP instead? I feel like I'm caught in a classic circle of confusion, no longer being able to tell with confidence if the tonality of my music is right or not, and seemingly having no dependable way to know how I should actually be EQ'ing these speakers above 300Hz for decently accurate response. I mean, can we simply not own speakers if they are too old to have spinorama data available?

As might be obvious from this post, I'm kind of at the end of my rope at this point. I feel I've tried my best here and I'm most definitely not having fun anymore at this point. I would be grateful for any perspective, guidance, advice, or helpful thoughts anyone can provide, to help me better understand what I'm looking at here and perhaps how I might come to an informed decision about continuing to work with these speakers versus giving up.

Thanks!

Frankly, 10 to 15 dB FR variance in an acoustically untreated room is actually pretty good. I've seem as much as 25 dB...

Try some EQ on it before giving up.

 

[tmtomh]

F

Frankly, 10 to 15 dB FR variance in an acoustically untreated room is actually pretty good. I've seem as much as 25 dB...

Try some EQ on it before giving up.

Thanks! I agree. My room is somewhat acoustically treated, actually. But I take your point, and I've realized that most of the speaker response graphs I look at day-to-day are Amir's spins, which of course are going to be much smoother than actual in-room measurements.

In that regard, I agree that the Kappas' response actually looks pretty darned decent from 20Hz up to about 3.5kHz. It's the dip from 3.5k to 7k that looks strange. (The hump at 10k, followed by a fairly fast/steep dip from 12k to 20k makes the whole thing look worse/weirder, but I'm not concerned about that since I've confirmed that the super-tweeters are working fine, and nothing in that range has ever bothered me in the least when listening to the Kappas.)

For the 3.5-7k region, I tried a bunch of different things - toeing in, toeing out, full-range Dirac correction, Dirac from 20-300Hz only plus a little manual PEQ up higher, peak PEQ, high-shelf PEQ, no PEQ at all and just letting them be what they are, adjusting the L-pads on the back of the speakers, re-taking Dirac measurements and generating new filters, using different target curves, moving the listening position a little forward or backward.

Some measures helped, some didn't. Overall I definitely made progress - but I never got to a point where I could put on any recording in my collection and feel confident that it would sound right. Something seemed to be going on in the upper mids and lower treble that, as best as I can tell, requires multiple fairly precise PEQ filters to attenuate certain frequencies while boosting or preserving others. I didn't manage to crack the code, and after a while I thought, "Why the hell do I need to crack a code? Why not just get a pair of actives that I know for a fact are super-linear anechoically, have low distortion up to and beyond any SPL I could stand to listen to, have sufficient bass extension, and have built-in room-correction DSP?

So that's what I did. And as soon as I hooked up a source to them and turned them on, they just sounded right with any recording I threw at them. I quickly heard an obvious, very annoying room mode in the 60-90 range, and I was pretty sure there was some excess energy in the 200-500Hz range somewhere from room reinforcement, But even in that pre-room correction condition, the speakers produced the consistency of sound across recordings that enables me to relax and just listen: brighter recordings sounded bright; warm recordings sounded warm. Trebly but non-harsh recordings didn't sound harsh, and trebly and harsh recordings sounded harsh. Male and female vocals sounded equally forward, and neither sounded excessively sharp or piercing. Moments of sibilance that I know are sharp sounded sharp, while moments of sibilance that I know are less prominent were noticeable but not sharp. There was no mystery to be solved, no perplexing situation where some recordings sounded right and others sounded off, and if I applied fixes to get the off ones to sound right, then some of the right ones would sound offI couldn't seem to get them all to sound right at the same time.

I know this can be seen as subjective, circle-of-confusion stuff, but I hope I've managed to convey the difference between (a) my new speakers, which might have limitations or in-room response nonlinearities but sound consistent across all the recordings I throw at them, and (b) the Kappas, which are lovely in many ways, really incredible in some ways, but in my experience exhibited a frustrating inconsistency with different recordings.

 

[dlaloum]

That said, whether I took 3, 5, 9, or 13 measurements with Dirac, the frequency response graphs didn't vary a whole lot.

These measure the room... so include all reflections... rather than the direct sound alone...

It would be nice if Dirac provided a time gapped measurement as well, so that we could see the direct sound seperate from the room...

 

[audiofooled]

Could it be possible that the replacement polydome midrange driver is not exactly the same, like so it extends a bit further up in frequency than originally intended?
In which case it's size/wavelength, not to mention the shape could interfere with the tweeter above and introduce some lobing/phase cancellation effects?

That 5kHz (6,86cm wavelength) dip is looking a bit fishy if I think about it. Given the height of the loudspeaker and potential angles at which this could happen, also that there are floor/ceiling reflections, and the rear tweeter, this could possibly result in a very uneven response at listening position. You could try to measure at different height or simply have a listen if the dip goes away and comes back again. Or with the recordings that sound off, for that matter.