Tekton style like tweeter array good idea?

[mhardy6647]

@Sal1950 thanks for filling in the blanks on Hafler, Keros, and UL.
I was stretched a little thin yesterday & didn't have the bandwidth to put anything together (in my defense).
Late in the "real" Dynaco's history, their high powered ss power amps (the ST-400 and ST-416) were nontrivial players, too. James Bongiorno (later of SAE, GAS, Sumo, and finally Spread Spectrum Technologies) cut his teeth on the 400's development program, if memory serves. Bongiorno, of course, also left a legacy of sartorial elegance.
It's also worth noting that Hafler's AFAIK last (and eponymous) company turned out some nice stuff, as well. There is an ST-400 in the basement (imagine that?!) but I have to imagine it is a basket case, and I dont' have the gumption to even start on repair and rehabilitation of such a monstrosity.

The Dynaco ST-70's not my personal favorite pp EL34 amp, though, in full disclosure. That'd be the Marantz 8B. EICO's very Williamson-esque kit pp EL34 amplifiers (integrated and power amps, mono and stereo) were also very nice, with excellent output iron. My own first hifi amp (which I seriously wish I still had) was an EICO HF-52 (pp El34 mono integrated with multiple phono preamp EQ curves, variable loudness, and fine Chicago iron) that my father rescued from an old church PA system that he upgraded (to the then-ubiquitous Bogen Challenger amp). But I digress...

 

[Marchio]

Welcome to ASR!

Exciting speakers you have put together. I see a 5 dB boost from 6 kHz to 10 kHz with your speakers. A matter of taste if you like that. I had ..., hum when I think about it tried with an amplifier with a treble control and twisted it a bit. They usually operate around 10 kHz and get below that frequency a falling FR when in use. Maybe not the most optimal because what happens then from 6 kHz and below? But on the other hand, if you have an amplifier with that function, you can do a test. That's what tone controls are for.

On the other hand, if you listen at low volume, there is already a built-in loudness compensation for the higher frequencies with your speakers.
____
You mention Dynaco A25. They have figured in the thread below. A thread that I think you will like:

Audio Note speakers

What's the deal with Audio Note speakers ? They have so many models and they're not exactly cheap (can cost over $100K) And it seems they're "legendary " speakers on other audiophile forums. What's so special about them ?

audiosciencereview.com

Yes, you are right. And perceptive. The high mids are not shy with the Karlson+AMT rig. I mean, the Cornwall has 3 bumps, one centered on each driver. This has one big bump! But, dare I use the term, psychoacoustically, this is somewhat masked by two things. First the bass goes so deep and is so musically definite as actual notes that it seems louder than it is because it is so clear. And, likewise, the AMT tweeters are so fast, subtle, and clear that the highs above 10K also seem louder than they are. There is something odd about human hearing which is that we tend to think clarity = loud. Oddly, we are also really bugged by by distortion, especially positional distortion. A bad stereo image will make this keen listener feel sea sick. So not only is there one broad peak that I have come to like in this context as adding clarity, but the stereo image is intentionally air brushed. I softened it intentionally with the open back AMTs room reflections to give a more immersive, balanced but less abrupt and pinpoint sound stage. This sort of works I judge to balance the upper mid peak, again psychoacoustically. "One side makes you larger and the other makes you small."

I can hear folks asking, "Why not just do it right in the first place?" But where's the fun in that? I want every system I build to sound recognizable, to have its own character, but still be as lovely as a warm bath or the smell of honeysuckle, magnolia, and roses on a warm humid summer evening in Richmond, Virginia's near Westend after the rush hour exhaust has blown away and before the dew has settled subduing the magic of those sexy floral allergens.

 

[DanielT]

Yes, you are right. And perceptive. The high mids are not shy with the Karlson+AMT rig. I mean, the Cornwall has 3 bumps, one centered on each driver. This has one big bump! But, dare I use the term, psychoacoustically, this is somewhat masked by two things. First the bass goes so deep and is so musically definite as actual notes that it seems louder than it is because it is so clear. And, likewise, the AMT tweeters are so fast, subtle, and clear that the highs above 10K also seem louder than they are. There is something odd about human hearing which is that we tend to think clarity = loud. Oddly, we are also really bugged by by distortion, especially positional distortion. A bad stereo image will make this keen listener feel sea sick. So not only is there one broad peak that I have come to like in this context as adding clarity, but the stereo image is intentionally air brushed. I softened it intentionally with the open back AMTs room reflections to give a more immersive, balanced but less abrupt and pinpoint sound stage. This sort of works I judge to balance the upper mid peak, again psychoacoustically. "One side makes you larger and the other makes you small."

I can hear folks asking, "Why not just do it right in the first place?" But where's the fun in that? I want every system I build to sound recognizable, to have its own character, but still be as lovely as a warm bath or the smell of honeysuckle, magnolia, and roses on a warm humid summer evening in Richmond, Virginia's near Westend after the rush hour exhaust has blown away and before the dew has settled subduing the magic of those sexy floral allergens.

You have a good attitude towards your HiFi project!

Speaking of experiencing distortion. I think that those who have worked professionally with sound and had the task of, for example, to design and thus also work on getting low distortion in speaker elements/drivers and have done a lot of blind tests have over the years learned to "sniff upp" distortion experience it in a completely different way than, let's say, what I do. You know Erin, who has Erin's Audio Corner, measures and talks about distortion levels. Here's what a person with professional experience described has to say about that:

Also, he seems to be almost totally tone deaf when it comes to distortion. I therefore only take part of his measurement results, which of course via Klippel NFS are excellent.

faktiskt.io • Visa tråd - En annan liten räv

www.faktiskt.io

What I've clearly experienced is when it's really bad; think old low powered crappy car stereo where the volume is turned up and the amplifier is driven into clipping. Then it can sound bad, really fudging bad AND subjectively loud. But if you measured the SPL level it would probably only be at a modest level. By the way, the same SPL level with a sufficiently powerful amp and decently low distortion speakers would be pleasant to listen to and not at all perceived as a particularly high volume.

 

[CedarX]

Speaking of experiencing distortion. I think that those who have worked professionally with sound and had the task of, for example, to design and thus also work on getting low distortion in speaker elements/drivers

Then it can sound bad, really fudging bad AND subjectively loud. But if you measured the SPL level it would probably only be at a modest level.

Is this because, as professional, you’ve learned (unconsciously?) that ‘bad distortions’ = ‘loud’?

Or, it’s an established psychoacoustic phenomenon, true for all listeners? Any reference papers?

 

[dfuller]

Is this because, as professional, you’ve learned (unconsciously?) that ‘bad distortions’ = ‘loud’?

Or, it’s an established psychoacoustic phenomenon, true for all listeners? Any reference papers?

Distortion definitely has an impact on perception of loudness. Specifically - more distortion makes speakers seem louder than they are, even if it isn't gross distortion. High output speakers can be turned up insanely loud without sounding loud.

I can turn my KH420s up louder than I can stand (which is like, "rattle stuff off my shelves" loud) and they are still in control; at the same volume as a higher distortion speaker, they don't sound as loud.

 

[mhardy6647]

Wait?! We've got Karlsons in this thread now?
Oh the humanity.

Couple of Karlsons in the basement* - one genuine K-15, and one a Fukuin (Pioneer) K-12 clone of sorts.
The former is loaded with a Stephens-Trusonic 206 AXA (a rather redoubtable coaxial); the latter with an EV SP12B "fullrange" twincone driver.





_________________
* 'nuff said.

 

[DanielT]

Is this because, as professional, you’ve learned (unconsciously?) that ‘bad distortions’ = ‘loud’?

Or, it’s an established psychoacoustic phenomenon, true for all listeners? Any reference papers?

Some factors that determine how good or bad you are at detecting distortion:Training, mood and attitude and maybe genetic conditions that differ?

In any case, for me it's no contest.Not even an end in itself to become better at sniffing out distortion. That could lead to me having to buy better HiFi stuff then.

I'm about average when it comes to spotting distortion. If you are curious, you can also try:

How Much Distortion Can you Hear?

An interesting test probably posted before although it didn't come up in a search. Also try difference sources ie ear phones vs speakers.

audiosciencereview.com

Distortion Listening Test

Ran into this interesting listening test by Klippel with regards to how much distortion you can hear. This is the link: http://www.klippel.de/listeningtest/lt/ Just casually wanting to see the test, I went with the defaults and for some reason, the levels were exceptionally low. I had to set...

audiosciencereview.com

 

[Ropeburn]

Because the thread is about Tekton. The Dynaco ST-70 Series 3 together with the Tekton Enxzo XL would probably be a good match.

...90.6dB(B)/2.83V/m...remains above 6 ohms at all frequencies...The Enzo XL is therefore well suited for use with low-powered tube amplifiers.

FR looks pretty ok, other than around 1kHz to 3kHz. A little extra bass boost for those who like that:
The roller coaster around 2 kHz is a shame because we are sensitive to deviations in that area.
View attachment 415020

Tekton Design Enzo XL loudspeaker Measurements

Sidebar 3: Measurements I used DRA Labs' MLSSA system and a calibrated DPA 4006 microphone to measure the Tekton Enzo XL's frequency response in the farfield; and an Earthworks QTC-40, with its small, ¼"-diameter capsule, for the nearfield responses.

www.stereophile.com

Edit:
Why not one, 1 sufficiently sensitive tweeter or a compression driver together with the bass drivers in the Enzo XL in a 2.5 crossover solution? Okay then it would not have been Tekton with array tweeters but it would have been a more sensible, "normal" solution. Even better is a traditional three-way speaker with the two bass drivers in the Enzo XL, but then it's a different type of speaker we're talking about.

Good heavens, what a mess. Those dips in the midrange are horrible, so is that pesky resonance at 300Hz.

Overall very unbalanced with serious issues. Not worthy of a speaker for 2000 the pair. Not even the woofers are mounted flush.

 

[Marchio]

You have a good attitude towards your HiFi project!

Speaking of experiencing distortion. I think that those who have worked professionally with sound and had the task of, for example, to design and thus also work on getting low distortion in speaker elements/drivers and have done a lot of blind tests have over the years learned to "sniff upp" distortion experience it in a completely different way than, let's say, what I do. You know Erin, who has Erin's Audio Corner, measures and talks about distortion levels. Here's what a person with professional experience described has to say about that:

Also, he seems to be almost totally tone deaf when it comes to distortion. I therefore only take part of his measurement results, which of course via Klippel NFS are excellent.

faktiskt.io • Visa tråd - En annan liten räv

www.faktiskt.io

What I've clearly experienced is when it's really bad; think old low powered crappy car stereo where the volume is turned up and the amplifier is driven into clipping. Then it can sound bad, really fudging bad AND subjectively loud. But if you measured the SPL level it would probably only be at a modest level. By the way, the same SPL level with a sufficiently powerful amp and decently low distortion speakers would be pleasant to listen to and not at all perceived as a particularly high volume.

I find the basic Tekton idea interesting. That is, handing the mids with tweeters has advantages with speed, transparency, and detail. But so far I have only used AMT bi-directional drivers and compression horns.

Thanks for the replies. And the link. Yeah, I was listening yesterday and decided I was fooling myself. Yes, the system with the 4 generic horn tweeters, probably unlabeled 5Core CD 110 or some sort of cone from Temu, has a lot of upper mid. Probably too much. And the dynamics seem exaggerated in that range too, probably about 4 to 8 kHz. The effect is odd because vocals are clear, but when an operatic soprano hits a high note . . . Ouch!

You need to understand that each channel has 4 tweeters, each with a 3 lb. magnet. Very efficient and fast!

So I made 3 changes. First, I replaced 2 of the 15" horns with 10" horns and swapped the 19 uF cap on those drivers for a 5.6 cap. Then I pointed the original 15" horns with the 19 uF caps up toward the ceiling on the smaller horns directly at the listening position. Well, this dramatically improved the naturalness of vocals. No more early ear fatigue. But the sound still has an effortless quality with just a watt or two loud and clear.

I also added a .3 coil to the K-33-4 woofers.

So now the woofer kicks in solidly by 35 Hz and falls off starting at about 2 kHz. The large indirect tweeters cover 1.5 kHz to about 18 kHz and the smaller direct horns come in around 8 kHz to 18 kHz. This compensates for the compression horn being a bit mid heavy, but keeps the sound really integrated since both the low and high tweeters are the same drivers. This has some advantages of a two-way in smoothness and integration and a three-way in definition and mid presence.

The sound is much better like this. But I am still working on how to position the tweeters. I very much doubt Tekton's solution will really work right to give one a point source experience like, say, a Design Acoustics PS-10 does. But then neither will mine, but I am hoping to get a pleasant level of stereo effect and a convincing stage.

 

[Marchio]

Can the Tekton speakers possibly do what is claimed with respect to point source imaging for them by financially interested parties?

Let's play Einstein (or Hawking) with a thought experiment mainly in pictures to try and answer a question too complex for a purely mathematical model:

OK. Place two speakers 2 feet apart about 6 feet away from the listener's position. Have some one else switch some music from one speaker to the other with no changes other than position. Can you hear the music jump from one speaker to the other as the switch is made?

Well, the answer is YES. I know because I tried this experiment in the world after wondering about the thought experiment!

Now, change the frequency. OK, I'll cut to the chase: so long as there is enough high frequency info in the music, one hears the jump. With a very low test tone, one does not. No, I am not going to re-do the experiment with better notes to tell you the exact frequency at which the two speaker's perceived positions merge. But it's probably lower than you think. Like below 120 Hz or something like that.

OK, so anything a tweeter or squawker is likely to produce is highly positional. But we all know that, right?

I moved the speakers together and apart. Well, as you would suspect, they had to be very close before I did not hear the jump. Like nearly touching when I was 6 feet away. At 8 inches, the positional jump was clearly audible at vocal frequencies. Makes sense. After all, we evolved locating mates and predators hiding in the tall grass. Right?

Now, add this twist. It's a little harder to wire the switch, but I have faith in you if you're a regular on this site. Add a third position which is both on. And add a third speaker in the fixed in the center between the other two, also 6 feet away from the listener.

Now, can you hear a change when you switch from both speakers to the center speaker? Again, play with frequency and move the outer two speakers closer and farther from the center one. At what points does any perceived difference disappear and reappear?

Now, I admit it; I lost interest during this final experiment once I realized how easy it was to tell a "ghost center speaker" from the real McCoy.

So what does all this have to do with Tekton?

Well, I think their circle of tweeters at vocal frequencies will always be distinguishable from a coaxial or conventional point source design, again such as the classic Design Acoustics PS-10. Do you see why?

I think the spacing of the drivers is too wide and the frequencies too high not to have some effect on the sharpness of the sound stage. I admit that the whole circle thing gives me pause; a circle of tweeters is certainly different than 2 side-by-side. But even though I am not from Missouri, in this case, I would say, "Show me." Because in all my speaker designs, sound stage is the hardest thing to get right. If two sound sources are differently positioned, it is very hard to fool human ears into hearing them as the same. And these Tektons are certainly different. As unique as the Bose 901 or Design Acoustics D-12, coaxial or single driver or open baffle designs. And they all have, love them or hate them, their own distinct sound signatures.

Anyone giving away a pair? Or live in Richmond, VA? No, I don't have the scratch to buy them just to test and add them to my collection of over 350 set of loudspeakers. Mostly deservedly in storage!

 

[mitchalee]

I have several period systems. Sansui, Pioneer, Dynaco, Bozak, Warfedale, etc.

The Dynaco consists of A25s but with newer Dainish made SEAS woofers that closely match the originals but reach a bit farther into the mids. Sometimes this is unfortunate. But other times, it is clearer what the vocalist is up to. A Stock Stereo 70 completely in spec. A simple Dyna valve preamp. Thorens 415 table with a Shure V15 II Improved. Original stylus in great shape. I would use a Denon DL103, but the Dyna preamp does not have enough gain for a standard MC.

Also the original FM only valve tuner in fine shape and well adjusted.

For acoustic guitar singer songwriter or combo jazz, it can't be beat. The only thing that come close is a great Jansen Electrostatic system which has much flatter, deeper bass, But the SEAS dome tweeter actually outshines the powered elecrostatic panels. Really great tweeters! Also the Jansen cost 5x more.

 

[mitchalee]

Welcome to ASR!

Exciting speakers you have put together. I see a 5 dB boost from 6 kHz to 10 kHz with your speakers. A matter of taste if you like that. I had ..., hum when I think about it tried with an amplifier with a treble control and twisted it a bit. They usually operate around 10 kHz and get below that frequency a falling FR when in use. Maybe not the most optimal because what happens then from 6 kHz and below? But on the other hand, if you have an amplifier with that function, you can do a test. That's what tone controls are for.

On the other hand, if you listen at low volume, there is already a built-in loudness compensation for the higher frequencies with your speakers.
____
You mention Dynaco A25. They have figured in the thread below. A thread that I think you will like:

Audio Note speakers

What's the deal with Audio Note speakers ? They have so many models and they're not exactly cheap (can cost over $100K) And it seems they're "legendary " speakers on other audiophile forums. What's so special about them ?

audiosciencereview.com

As I agreed, yes there is a boost in the range you mentioned. After a while, it did start to annoy me with female vocals and trumpets. So I left two of the compression horn tweeters per my original design except that I swapped out the 19 uF cap for a 15 uF. Then I replaced the 15 x 5 " horns on the other 2 with 10 x 4 " and the 19 uF cap with a 5.6 uF cap. Remember, we are working into 4 Ohms because the two sets of tweeters are parallel. In any case, this smoothed out the bump . . . some . . . by halving the volume of its frequencies and doubling the volume of ihe frequencies above it. Seat of the pants estimates. Still a work in progress. Oh, also added a .3 inductor to the woofer to cut it at about 2K. Now, the math says this would give me a hole from 2 to 3 kHz. But my ears tell me that's not so. Who do you trust? Me? I trust my ears over physics. Guess I'm just playing God. Right?