Doubt about tweeter choice (DA25XT00-08 or SS 2608/913000?)

[cereal killer]

Hi everyone!
The tweeter in question will be paired with an old Accuton C79/6 midrange and crossed at 2.5-3 kHz.
At the moment two quite different products attracted my attention: the Peerless DA25XT00-08 and the SS 2608/913000.
At present the main uncertainty is related to their sound performance.
I therefore turn to those who have had direct experiences with the two loudspeakers, asking for your feedback referring to mere musical qualities.
To be clear, I don't expect you to comment on a direct comparison between the two tweeters, I can imagine it's not that common to have both. I just need your opinion on the sound quality of the tweeter of which you have direct experience.
Thanks to those who will have the patience to help me.

[JonMarsh]

I have used or abused both...

:W

The D2608 has relatively low Xmax, and rolls off a bit earlier than I care for in the bottom end (that makes the crossover design more challenging unless you go for high order slopes;

I paired it with a carefully chosen waveguide to extend the performance envelope and output capability, while getting pretty consistent off axis behavior.

https://www.htguide.com/forum/showthread.php?35524-Modula-MT-XE-You-didn-t-ask-for-it-it-s-coming-anyway&highlight=Modula

Direct versus waveguide:



Polar behavior:



Measured system distortion, showing tweeter contribution:




==================================================


The first system I used the DA25TX008 in was a two way for Steve Manning as a proof of concept for the TTC enclosure construction.

https://www.htguide.com/forum/showthread.php?44329-A-New-Adventure&highlight=adventure

The DA25 has excellent polar behavior, substantial Xmax, and very low distortion, but like many hard dome tweeters, it has a high Q resonant breakup, which should be addressed with a notch filter in the crossover in order to reduce resonant amplification of distortion products from signals below the break up mode.

Polar response from 0-30 degrees



Frequency response and distortion for the Calliope two way using the DA25TX, with HD2 and HD3 plotted.



The high frequency distortion looks quite a bit different without the crossover network.


The DA25TX is a more modern design, but it is physically large and could be an issue for some designs.

[cereal killer]

Thank you very much.
Technically I "know" the two transducers sufficiently, I have been digging on the net for some time looking for electrical and acoustic measurements.
I am quite convinced that they could both be usable in my project, but at this point I would be very interested in some opinion on the sound of these loudspeakers. You who used them both, can you tell me something about it?
Furthermore, with regard to the DA25TX, I cannot explain why in the pdf downloadable from the manufacturer's official website, the material used for the dome is said to be aluminum and not curundum.

https://tymphany-driver-files.s3.us-west-1.amazonaws.com/files/driver/pdfs/DA25TX00-08.Rev1.MP1%20-%20Product%20Sheet.pdf

Thanks again!

[tktran]

I think Jon has explained in as much detail as he could.

A man once said "I used XXX driver in my last YYY design and it sounded ZZZ."
( Replace X, Y and Z with anything ) It doesn't matter what, because statements like that don't have much merit.

A wiZe mAn once said:
When a driver is used in a system, only the system as a whole can be evaluated. (and even then, as mentioned above, not without measurements) Of course the drivers are making sound, but what you really hear is the crossover, design choices and the listening environment. So many people evaluate drivers while they are in a poorly designed system and then blame the result on the drivers themselves. Only individual and extensive driver measurements are acceptable in evaluating an individual driver.

[cereal killer]

In principle, I agree with what you say.
What you hear is the assembled and fine-tuned recipe.
But I think that the single ingredient (the speaker, a tweeter in this case) tends to have its own sonic signature anyway. My old Accuton C23/6 for example, I have implemented it in different configurations, the sound always changes, but its sound is always recognizable in some way.

[JonMarsh]

OK, let's just say that a number of folks that have heard my implementation of the DA25 say that it compares well with $400 Be dome tweeters in other systems I have designed...

My own take on the DA25, it that if properly implemented, it is the most accurate and best performing $400 tweeter you can buy for under $100. It has the best polar behavior of any dome tweeter I've measured or heard for flat baffle mounting. That contributes to uniformity of power response. It doesn't just "twinkle" on axis.

If you have a mediocre DAC, it will reveal that ruthlessly. If you have a mediocre crossover, ditto. I can't think of any greater endorsement than the measurements I provided above. It's more useful and objective than my comments about precision, transient response, and general transparency, which are merely subjective ways of describing what can be measured- if the performance is there.

Others who have heard the Calliope with the DA25 have been very impressed, including with the HF performance (BTW, 1800 Hz crossover). The DA25 has also been used successfully in an Ardent class systems with Accuton cell woofers. So it plays well with the big boys. (Note, dual RSS265-PR on back are not visible)




Here's the measured performance in the Ardent D Duelund system:






I experimented with the D2608 in several system configurations, and the only one I was happy with it's performance was the waveguide Modula MT XE two way. In that configuration, the performance comes together, and the distortion and power response /polar response are much better than the tweeter mounted on a baffle. So, that is my "conditional" endorsement of the D2608.

[cereal killer]

Many thanks JonMarsh!
Have you a DA25 waterfall plot to show?
I haven't been able to see one yet.

[fatmarley]

When I tried the DA25 I couldn't get it to sound good. It was either too bright or too dull. I didn't notch the breakup peak because my microphone doesn't measure that high. Would that have been why I couldn't get it to work?

[cereal killer]

It was either too bright or too dull.

It is not very clear to me what you are saying, can you explain yourself better please?

[Efalegalo]

Others who have heard the Calliope with the DA25 have been very impressed, including with the HF performance (BTW, 1800 Hz crossover). T

I was super impressed with the Calliopes. I got a chance to hear them at Sven's. They may not be the last word in bass authority, but still surprisingly pleasant enough bass in a small room. Absolutely excellent mid+highs, though.

I'm glad I have two pairs of those tweeters sitting at home. Not sure if the Calliopes are an open design - but if they were - they would be on my shortlist. If not the Calliopes, I look forward to Jon's revival of the NatalieP DA's with the new tweeter.

[Steve Manning]

I was super impressed with the Calliopes. I got a chance to hear them at Sven's. They may not be the last word in bass authority, but still surprisingly pleasant enough bass in a small room. Absolutely excellent mid+highs, though.

I'm glad I have two pairs of those tweeters sitting at home. Not sure if the Calliopes are an open design - but if they were - they would be on my shortlist. If not the Calliopes, I look forward to Jon's revival of the NatalieP DA's with the new tweeter.

A quick comment on the bass performance on the Calliope's ..... room placement from what I've seen in pictures that Sven has shown, might not be ideal. I found that to be the case when I set up the prototypes in my space. Of course this is true for any speaker. I'm not talking spending days to tweak to the last 1/8", but when you get it in the right spot, all kinds of things fall into place.

They will get down there when needed, but being a two way, you can can do only so much.

[fatmarley]

It is not very clear to me what you are saying, can you explain yourself better please?

When voicing the tweeter I couldn't find a happy medium. I tried perfectly flat, slightly rising, slightly falling and pretty much everything in between. I can only think it was because I didn't/couldn't notch the breakup.

[JonMarsh]

To clarify the use of the DA25 a bit further, I'm going to share another recent example.


Back about five years ago I did a special "mid priced" design version of the Ardent for Renron- Ron Bradley. The target was to cut the midrange and tweeter driver price, so it moved from the Accuton C79 and Scanspeak 6640 beryllium dome tweeter to the Scanspeak 12MU4731 on midrange duties, and the 66000 soft dome for the tweeter. Ron felt it met his goals pretty well, and since the 12MU4731 is still available, unlike the Accuton midrange, we've had inquires about another spin on that approach, but perhaps with a high performance hard dome tweeter.


That resulted in this design proposal, this week, using all the existing measurement files (which really saves a lot of time!)

Here you can see an example of a pretty solid implementation for the DA25TX008.


The updated crossover schematic:




The basic SPL response overview...





The impedance curve (the 12MU4731 is a 4 ohm nominal driver, which does make things a bit trickier in keeping a reasonable impedance range)





And a look at the crossover behavior details:




Note, the crossover is my typical Linkwitz-Riley style 3rd order, drivers in phase and down -6dB at crossover point, and this example has very good reverse mid connection nulls. Yes, 3rd order LR is not an actual thing, but for real drivers with progressive rear offsets and time delays, it can work very well and sum nicely- I've rarely seen other people describe this, but I've been using it in series and parallel crossovers since the first Modula MT and NatalieP. There's a thread describing it... can you find it? :W

Here's a picture of the mid priced Ardents the earlier version was used in.




I visited Ron to solve what turned out to be a minor problem- the midrange driver's connected backwards. Nice guy, and a superb quality build.

[theSven]

A quick comment on the bass performance on the Calliope's ..... room placement from what I've seen in pictures that Sven has shown, might not be ideal. I found that to be the case when I set up the prototypes in my space. Of course this is true for any speaker. I'm not talking spending days to tweak to the last 1/8", but when you get it in the right spot, all kinds of things fall into place.

They will get down there when needed, but being a two way, you can can do only so much.

I have to admit I never listened to the Calliopes without a sub when I had the Emotiva UMC-1. Since upgrading the Emotiva and not having it fully setup I listening to them with out the sub and I was very impressed. Yes my room placement is not ideal, but on the other hand the fact that they they sound great is impressive. I have since relocated the Calliope upstairs to the den and I have an old Pioneer receiver from 2011/12 that I'm using. The bass upstairs is phenomenal and the speakers are not smack against the wall like before. My room mate came out and asked one night why I hooked the sub up and I told him that it's not and all the Calliopes.

[fatmarley]

Note, the crossover is my typical Linkwitz-Riley style 3rd order, drivers in phase and down -6dB at crossover point, and this example has very good reverse mid connection nulls. Yes, 3rd order LR is not an actual thing, but for real drivers with progressive rear offsets and time delays, it can work very well and sum nicely- I've rarely seen other people describe this, but I've been using it in series and parallel crossovers since the first Modula MT and NatalieP. There's a thread describing it... can you find it? :W

I've done it in, and tried to descibe what I did over at the partsexpress forum, but was told there is no such thing. It does seem to work very well in some cases, so I'll still use it, even if it is a figment of my imagination