My open baffle journey

Much better. Images are no longer bunched together laterally and there is imaging outside the bounds of the speakers (guitar).

It’s still a little forward in character (freq. response issue?) and imaging could be a bit more precise (probably due to diffraction at baffle edges at higher freq.s even if low in Spl), some of this latter issue could be mitigated with the tweeter’s high-pass at a lower freq.).
 
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Many thanks Scott!
Yes, I think too it's much better now.
I think this very song is recorded to be forward with piano and guitar; I made a check with a factory speaker (Sonus Faber) and it's the same with it. I will make a new demo with another song. However, I like the somewhat lively presentation, until it's not "hot", shouty and/or harsh - and now I think it's not.
Yesterday I ordered new birch ply baffles (mine are MDF) with rounded edges and I also will round the corners, and with recessed mounting of the FR, I think it will help too. After this I will play with the tweeter depending on the behavior with the new baffle.
But I'm already very happy with it as is.
 
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Hi again,
I just had an aha moment... Is it possible that not every power amp can drive every speaker properly, in terms of control? Instead of my class A power amp, I connected my high-end class D power amp and was shocked at how problem-free, smooth and clear the upper mids sound. No trace of sharpness, of foregrounding, or of anything disturbing... is this possible?
 
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Thanks Scott!
With "not quite as smooth sounding" do you mean compared to the class A amp?
Sitting here live and listen to the same music again and again tells me that the nasty shouty "peaks" are gone, that's what I mean saying "smooth". "Lively" is still here and it can act against "smooth", but I think it's largely personal taste.
 
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Not a “peaking” quality (in this instance for me through the recording with the class A amp), more like notes are sort of compressed at the end sometimes referred to as slightly “rounded” - you don’t get as much decay, whereas the most recent recording (Class D) allows you to hear the decay and hall sound a bit better providing enhanced clarity and depth.

Sometimes with exceedingly expensive amps you’ll get both a slightly smooth rounded sound WITH extreme clarity and depth (The Griffon).

For loudspeakers you’ll find this sort of quality with the most expensive Morel tweeters used pretty low in freq.. (Ti VC soft dome).
 
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Thanks for the clarification Scott.
So, in summary, I can be more than satisfied, if I understand you right :D (and yes, I am)

Here in the picture it's me, listening to an extremely expensive equipment of one of my friends (Spectral, Wilson Audio, MIT cables, etc...)
Great clarity end everything, but after listening to open baffle or Magnepans (as did another friend who took the picture behind me) everything in a box sounds like - a box.

IMG-20230412-WA0001(1).jpg
 
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Yes, what you’ve got even with low-freq. extension being limited is better than most show exhibits IMO (regardless of cost).

I haven’t heard a good closed/vented box system that was overall better than a good open-baffle 70-300Hz. I will say though that the older large Kharma’s from almost a decade ago that used larger Eton woofers sounded really good harmonically with decent clarity in the same freq. range, different but close to being as good as open baffle from more than 2 demos I’ve heard (it was bass-reflex).
 
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Hi,

While focusing on loudspeakers, we sometimes forget that amplifiers (and even cables) have an effect on the sound. That said, some amps work better with some loudspeakers than (with) others. Synergy.
Example: I had Visaton B200 on Open Baffle. Was't happy with the sound until I comnected it to Pass F2 amp (and that amp had the highest distortion-on paper).
So, it is important to keep an open mind and try even what "shouldn't work" but it does :)
 
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Thanks Scott. I would never say that my OBs are better than a 120000-Wilson because it'simpossible, but I like the sound of my OBs (and that of any OB and dipol) more.

Viktor, there are so many sound-influencing factors, of course cables, but also fuses, power supply and current treatment, and, and, and. Things will be often categorized as woodoo, without trying them.
 
Vix, Pass F2 amplifier output impedance seems to be 15ohms, which would boost highs and lows relative to mids compared to low output impedance amplifier, unless you used some EQ. In addition the impedance would reduce driver motor distortion entering acoustic domain quite a lot. Even high amplifier distortion is often decade or two below harmonics generated by transducers, so if you compare acoustically measured total system distortion it is likely lower with F2 than the other amplifier (with low output impedance) you used. And, in addition frequency response would be "better" as already mentioned, I bet F2 changes sound a lot.
 
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It would be interesting to try a transconductance amp - F2 as an example.
Fullrange speakers often sound better (as it provides some "natural" EQ).
On the other hand my B&W DM601 that I had at the time, did not sound good with an F2. So...

Another observation:
Most class D amps that I heard (not expensive ones though) sounded a bit cold to me.
But, once I got to hear a cheap class D amp (tpa 3116 or so) which was preceeded by a tube buffer.
That was a "WoW, what the..." ;)
 
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Some highs roll off?:)

I've used only few amplifiers so do not really have experience to comment on amplifier sound, so following is just reasoning:
The audible effects F2 would mostly come from the high output impedance and how the speaker interacts with it, which likely makes quite obvious audible difference. Frequency response differences measured with a microphone are likely very audible, difference in driver distortion could be audible as well, and both these depend on the driver/speaker not just the amplifier.

Perhaps there are audible differences between amplifiers themselves like amount of higher order HD, or crossover distortion at low volume, SNR, but these are typically so low in fully functioning amplifiers I'm a bit skeptic these would make much audible difference in sound. Hence, I buy into the synergy stuff that amplifier and speaker work together, but even that is not black magic but could be predicted and reasoned before selecting amp for speakers. It must be this way around, amp for speakers, because speakers need to be selected to room and liking.
Order of importance and selection, which all needs to bubble up and support to achieve the first:
1. hearing system, you need to know what you like, you'll be listening sound in a room
2. room, often has practical issues like acoustics and utility function beyond stereo listening
3. speakers, select to suit the room and application, meets SPL and bandwidth targets and practical positioning
4. amplifier, suit the speaker

First one is the most difficult, to come up what you like and realistic how to achieve?:) Then does the room support the ideal? how about speakers putting sound into the room? these work in acoustic domain and all affect each other. Amplifier being only in one dimension, electrical domain, is about the simplest one to choose among these. Might be very important at the end, but if steps 1.-3. aren't correct then it's irrelevant in away, only half a victory because it might have to change if speakers must change.

edit. added coffee break preaching :D
 
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Hi Plott,
That latest recording (with your cat) sounds fantastic!

Congrats on having such a great sounding system you built yourself. Those are real keeper speakers.

I have listened to $13k to $25k B&W’s and Sonus Faber’s in a showroom with $100k worth of blue glow Mac amps. I wasn’t impressed - I think my XSD dipole sounds better and can play just as loud with lower distortion. A lot of compromises are made on commercial speakers and sometimes, their XO is really awful if you look at the impedance plot or step response, you will see why.
 
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Hi Plott,
That latest recording (with your cat) sounds fantastic!

Congrats on having such a great sounding system you built yourself. Those are real keeper speakers.

I have listened to $13k to $25k B&W’s and Sonus Faber’s in a showroom with $100k worth of blue glow Mac amps. I wasn’t impressed - I think my XSD dipole sounds better and can play just as loud with lower distortion. A lot of compromises are made on commercial speakers and sometimes, their XO is really awful if you look at the impedance plot or step response, you will see why.
Hi X,
many thanks for the kind words, I'm really satisfied with the latest result (maybe it's the cat?:D).
We had the Vienna High End Show in November last year, with many demos, with bigbadabumm equipment and made the same experience.

@jmascreen it's the TB W8-2145.