How I Transformed My Home Listening Experience (Part II)

It's all good if you like what they do for your system, but if you take measurements you will indeed see comb-filtering effects. I just think potential buyers should know the science behind it and make an educated decision.

 

The human ear is just not sensitive to comb filtering effects that occur on the vertical plane.

It would, if our ears were positioned in the front of our heads and positioned vertically, I suppose.

Even on the horizontal axis, most center channel speakers use a horizontal MTM arrangement and sound bars use multiple small drivers mounted along the horizontal plane.

I have seen many speaker designs that have multiple tweeters stacked vertically.

I use JBL 2404 "baby cheeks" super tweeters on top of my Altec 511B sectoral horns and I have no issues at all with them.

 

I think that would be like doing the right job and using the wrong tool.

Something along these lines...

 

Speaking with reference to typical tower speakers.

Speakers that seem to play to the bass and the high frequencies, don't seem to get the midrange right, as that is not where their focus is.

On the other hand, speakers that focus on their ability to provide a natural sounding midrange, do often benefit from enhancing the top and bottom octave with supplemental drivers.

My Altec Lansing A7's as large as they are, are really just one big midrange driver.

With the addition of both a horn loaded super-tweeter and a large horn loaded bass bin, the become a 4-way full range speaker.

 

But, they could not make an educated opinion unless they heard them first. I could not hear this comb-filtering that you warn everyone about, so if I can't hear it, and only hear the improvements I have described, I am not as interested in a measurement someone may be right or wrong about. Obviously the company that sells these is confident in their product with the huge extended warranty and a 60 day trial, who does that these days? No, I am really happy with the tweeters, and have just not heard anything that sounds unnatural at all in the high frequencies.

 

Your polk speakers are beautiful. they look like salon2's with the grilles on. and excellent collection of sacd's, I'm more jealous of those then anything... 30-40 bucks a piece those go for...

 

It's not really my intent is not to turn people away from this product as it does change the sound. Some like this change and that's all well and good. Some like myself do find it causes audible detriment. That's subjective and we're all entitled to like what we like. The objective fact is it will induce comb-filtering if placed forward-firing near any typical sized cone/dome/ring/AMT/ribbon tweeter.

If we were talking speakers with full-range drivers, with only a whizzer cone for the treble, and the drivers were half- way down a tall baffle, then I can imagine a situation where the comb-filtering would be negligible.

I believe you when you claim you don't hear any ill-effects, but that doesn't mean your setup is exempt from the physics. I simply feel that any potential buyer should be aware of these physics, just as we all should be aware the Earth is round, even if it feels/looks flat.

 

Thanks so much for the kind compliment, I agree, I have found some really cool CD's and SACD's, most are beautifully recorded. When listening to some speakers, they are the right discs to do some good test listening.

 

I don't think that there is anything wrong with physics. Most vintage speaker makers designed their speakers around physics.

Which hasn't really changed much over the past century.

But they also designed and tweaked them to get the best sound from them. They did not simply rely on laboratory measurements to do this.

Laboratory measurements simply do not tell you how something is going to sound. It may provide you an insight but that is about that.

Back to the earth part. While it might be in fact round, the part that I live on is mostly flat.

If it measures round and the part that I interact with is flat, which is more important to my everyday life?

There are people who certainly hear better than I do. But if something is not audible to me, than it is way down the ladder in the order of things that I find myself concerned with.

I have played bookshelf speakers on top of tower speakers. Other people take monkey coffin floor standing speakers and stack them, one on top of another. The top cabinet being inverted, tweeter to tweeter.

Zu audio uses 10" full range drivers and a super-tweeter, with only a single cap as a crossover, like in the video. My Zu's are Omen Definition's, which have the tweeter mounted in between to 10" drivers.

If the OP does not hear anything and I have not heard anything but someone informs me that they measure wrong, is that going to be a concern to me?

As specially when I feel that something is an overall improvement?

Just as a note, I am and have always been someone who likes a good two way speaker system.

I think that I equally or maybe a bit more like the Altec's configured as a two way system, without the super tweeter but with a sub.

But I will also admit that for dome music, the super tweeter adds some air and a top end sparkle that simply is not present as a two way system.

When Paul Klipsch commissioned his Jubilee cabinets, he designed them to be the best two-way design that he could come up with.

So there is something to be said for both ways, I suppose?

 

Larry, I could be wrong here, but doesn't Audio Note design around "how their speakers sound" rather than by measurable specifications? It seems like I have heard that before?

 

Now you know why they put tone controls on electronics.

 

I'm just still not getting how this is different than using eq. This is just using an extra speaker to boost the high end instead of a knob.

I don't buy the subwoofer comparison. Speakers aren't nearly as close to flat at the low end.

 

Cool! Does the downward tilt of the super tweeter on your polks affect the vertical dispersion?

 

Might well have...

I can't speak for AN in the UK or AN in general. I have never been in a room with any one of the products, with the exception of the AN L4 Kit amplifier that I have.

It seems though, as I am given to understand it, that a good deal of the really high priced audio gear doesn't measure well.

But take for example a phono cartridge, then a tube phono preamp, then a tube line stage preamp, then the tube power amp and lastly the speakers.

How on earth are you going to take the specifications of each and every piece of gear in that audio chain an figure out how the whole thing is going to sould like?

It you change out a Ortofon 2M Bronze stylus for the Black Shibatta stylus, the entire system sound signature is going to change.

Change a rectifier tube in the phono preamp, bang, another change.

Move a speaker or change your listening position, yet more changes.

Change the volume level and the response changes.

I don't care about the measurements of any particular piece of gear. For me, the only factor that comes into play is the total system syenergy.

In the case of my former audio room, I had so many things going on at the same time. But the room and the sound environment that it created, was eight years in the making. Evaluating each component and how it played with the other components, one at a time.

At the end of the day, measurements have little meaning, how the system sounds means everything.

 

Generally speaking, I like tone controls, and if I bought a McIntosh pre-amp, you can bet I would buy the one with tone controls! With that said, the addition of the super tweeters gives a bit different sound than simply turning a treble knob.

 

I honestly do not know if I boosted 8,10, 12,14, or 16 Khz if the sound would sound exactly like the addition of a super tweeter, I just don't know?? I would think physically having a separate driver would present a different sound, however, since I have no equalizer, I can't speak to that.

 

You know, one of the things that really drew me to the Polk LSiM 707's was their tiny footprint. They do indeed look like other speakers you have mentioned. The newer super tweeters have the full ribbon design and the cases are larger and just look better on the Polk speakers, here is a quick pic of the new ribbon tweeters on the Polk LSiM 707's.

Left Speaker



Right Speaker

 

I would have to say that both the vertical and horizontal depression of these speakers is enhanced, fuller, richer, more detailed. The downward angle of the Polk cabinet could not be more perfect, as it tilts the super tweeter down ever so slightly, the tilt is mild, but it points the tweeter right in the sweet spot in my listening position, it's perfect and that is just per chance. I am hopeful others on the forum will give this very worthwhile tweak a shot, with a 60 day trial, they just sound so darn nice with both the Polk 703's and the 707's, so nice indeed! I should mention, the Polk speakers have a 1" ring radiator that really has a strong output, you have no problems hearing that tweeter, however the super tweeter just adds a delicate touch to every instrument and provide a more expansive presentation, richer, fuller, refinement, I was really amazed at the enhanced presentation, which is why I'm just so high on the addition of these little speakers. While the planar magnetic tweeters are wonderful, the ribbon design brings a refinement I honestly did not expect, not to mention the larger enclosure that seems to just look better on the Polks, a minor thing, but nice, none the less. I listen with the grills ON, I never remove them, so that may change the high end just a bit.

Recently I found this disc which had been remastered with lots of technical bells and whistles. If you want to research an album, look this one up, it was huge, and remains huge, featuring Radka Toneff and Steve Dobrogosz on piano. When I played this SACD on the Marantz SA-10 with the ribbon super tweeters, I was so amazed at this recording, I'm sure some of the folks on the forum have this blockbuster, absolutely beautiful piano! This is exactly the type of recording that truly shows off what these super tweeters are capable of, the clarity is captivating. Piano and vocal ONLY.


You will find this album or disc on Amazon, $56.35 for vinyl and $29.38 for the remastered SACD version, which is what I purchased, total killer sound.

 

I get what you're saying, but in my experience with these particular super tweeters, there was a very obvious and audible detriment to the other frequencies and I have zero doubt that at least some other buyers will notice a similar effect if they're a discerning listener. The measurements merely confirmed what I was hearing.

As I stated earlier, there's nothing wrong with enjoying the sound of these tweeters but they do in fact alter the original voicing of the main speakers upon which they sit. I imagine most potential buyers would like to be aware of that.

 

It would be hard to definitively say without doing an actual A/B comparison with both methods.

Having the 707's, I would think that the ribbon tweeter in the Aperion's is fundamentally a different animal than the ring radiator tweeter in the 707's.

I'm not sure that the ring radiator design would yield the same kind of sparkle and air that a ribbon tweeter might.

Two drawbacks ribbon tweeters sometimes have, when used as regular tweeters are that the are detailed, which can lead to them sometimes sounding somewhat thin and harsh, when played at high SPL's. Like ribbon microphones, they are by nature, not durable designs.

I think that a ribbon tweeter would be an optimum choice to add sparkle to a full range design.

On the subject of EQ.

I am not at all a fan of typical graphic equalizers. I think they do more harm than good.

If the situation does call for equalization, I think that a parametric design can perform a much in a far more specific and eloquent way.

But I also feel that EQ is better left to removing something that is there as compared to boosting something that is not.

I don't think using a parametric EQ to juice up the high end with a ring radiator, would accomplish the same thing and bring to the table, what a ribbon tweeter is capable of doing.

 

I'm sure the addition of these tweeters changes the original voicing of my Polk 703's and 707's, I have no argument against your opinion. In regard to most potential buyers would like to be aware of a change in the loudspeaker's presentation, I believe everyone understands your point that they should know that, as you mentioned that in your post #14, then again in your post #26, then again in your post #32 and again in your post #44, so I think everyone now knows that these super tweeters will change the presentation of any speaker systems they are used with, but I really disagree it degrades the presentation, it certainly did not do that in my case, and I listened very carefully for any high frequency cancelling or degradation, and I heard none. I should also mention this once more, the company offers everyone a 60 day trial, you have nothing to loose but the time it takes to wire them to your speakers, and you are done!

 

Beautifully written Larry, wish I had said what you did, especially in regard to the very different tweeter designs, a ribbon or planar magnet is going to sound different from the Polk ring radiator, it's just an entirely different design, and has different strong points, the detail of the ribbon driver is just so remarkable, BUT, after listening to these tweeters, I don't believe I would want a ribbon only tweeter in the system, they just work so nicely together. Thanks so much for your input, good stuff Larry!

 

Well I wouldn't have known about them and conducted the experiment had it not been for your original thread. They didn't work out for me but I did learn some new stuff so I don't consider it a waste of time. Indeed, anyone interested should give them a try and decide for their self. I just don't think everyone will have a similar experience is all.

 

Sometimes I am aware of something, even though I might not consciously be thinking about it.

But the 707's are some really massive speakers to have such a small physical footprint.

I mean, these speakers can really play BIG! With their 50% off retsil pricing, I can't think of any other speaker that you can buy for that price that has the quality of the RTi series and can play in a very good size room.

Yes, there are many fine audiophile big speakers. But, they are big and they are expensive. This places them well above what many can afford.

For $2k/pr. For the 707's and $1.5k/pr. for yhe 705's, this places a lot of speaker within the realm of affordability for a lot of people.

 

Thing is Larry, I think they still can be bought for that give away price, I would not sell mine for that, it's a real giveaway for sure, and they are GREAT loudspeakers.