Why Synergy horns?

In another thread I was asked, if I would provide more details about my speakers, so I thought why not?

I have played on active 4 way horn systems since 2016. First iteration was front loaded bass horn, midbass horn, tractrix midrange horn and tractrix tweeter horn. I worked nicely, with all the attributes associated with well implemented horns. Clarity, dynamics, realistic live sound etc.

However some problems will arise, with such horns. First of all, the center to center distance between the different horns is big, compared to the crossover frequencies. We need to be within 1/4 wave in distance at x-over for a seamless transition. For instance if you x-over from the midrange horn to the tweeter horn at 3 KHz the c-to-c distance would have to be 340/3000/4= 2.83 cm (1.11 inch). This is virtually impossible with "normal" horn configurations. This problem rears its ugly head, at every x-over throughout the audio frequency range. As frequency decreases, the wavelengths gets bigger, but so does the horns in the specific bandpass and then c-t-c also increases. It is a linear problem, that can't be solved with the regular approach, aka stacking horns on top of each other. This creates interference problems and lobing in the vertical response curves, that will color the reflection from floor and ceiling. Secondly a large column of vertically stacked horns, will push the sweet spot (SS) further back, for the horns to be perceived as more coherent and integrated, with one another.

But the biggest problem is that almost all horns beam with increasing frequency, it's their way of nature so to speak. What that means, is that the off-axis FR will not be similar to the on-axis FR. This translate into a poor power response, which is not considered a good thing, in terms of best sound quality.

Luckily we can circumvent all these problems with clever engineering and have our cake and eat it too, so to speak. Enter the Synergy horn.

 

Respectfully, don’t agree at all.
DSP is a “Band-Aid” and shortcut to achieve goals that can be achieved without DSP. The question becomes how much time, talent, and resources, does one have to achieve these goals without DSP? In a budget-friendly system, DSP is fine and a welcome improvement.
But for a product here in the “What’s Best” Forum, DSP is a not a solution I would ever buy into.

While at least part of your reply to @schlager is in a different context (i.e.: the particular usage) here, I'd like to point out that DSP isn't only about digital room correction in the amplitude and time domain, but can as well act simply and exclusively as a digital crossover in a fully outboard active context in which case it isn't a "Band-Aid," but rather a necessary means in place of a passive crossover situated prior to amplification on signal level. The added processing that comes with the potential room correction part, if one so chooses, can be heavier or lighter depending on how much need there is for acoustical compensation, and as such may leave a sonic signature or trace of varying degree that should also be viewed in relation to what it sets out to correct.

Speaking of Digital Signal Processing as having nothing else than a crossover function in an actively configured context, one must take into account what it replaces and brings in its stead, and not as something that is added to an existing, passive setup. You think an analogue crossover (and they're typically more complex than simple, not least with the segment of high-end speakers that're advocated here) is an ideal and non-intrusive insertion between the amp and drivers, even when it's analogue? How does it compare to having the drivers connected directly to their individual amp sections independently of each other, with all that entails, and with the active crossover/DSP placed ahead of the amps? If the DSP only has analogue inputs an extra A to D conversion is necessitated, but what does it amount to in the greater scheme of things compared to the negative effects of using passive crossovers between the amp and speakers?

Why?
You are converting to and from digital, and each conversion degrades the sound considerably. Even a digital source will need to be converted twice, depending on where the DSP conversion is in the chain.
I have never seen a high end DSP solution, where AC to DC conversion is well thought through and noise is minimized.

Stubbornly holding on to analogue and passive config. seems archaic to me, and fails to acknowledge the potential that can harnessed via a DSP-approach, also when it only acts as an active crossover. If it's still deemed an inferior solution simply with reference to the involvement of A/D to D/A conversion steps (or only D/A conversion with a digital input), then to my mind it's not seeing the forest for trees. One thing is putting format switches and their possible issues into words, but what do they actually amount to as perceived impressions, and in which context?

What is however considerable and noticeable to my ears is how passive crossovers impart their signature and restrictions on the sound, which only dawns on you when you hear what a well implemented active-via-DSP setup can do by comparison. From my chair that's just a different and fully viable approach to "What's Best" is also about.

 

I had similar questions concerning DSP in the previous pages of this thread. But passive filtering also degrades the sound, and filterless systems have their limitations as well. Each configuration has advantages and disadvantages.

Passive filtering doesn’t convert the sound into a completely different format. Not once, but twice.
A well designed crossover with a small number of components does not degrade the sound any more than an amp, with similar components, degrades the sound.

 

To DSP/EQ or not to DSP/EQ. When I talk to audiophiles I often get the feeling that they really do not want to optimize their sound. They tend to prioritize certain parameters, components or solutions that directly stops further development of the sound in their system. It seems that they think it is more important to have a nice box, a certain type of amplifier or to play analog sources etc. than to work further with DSP/EQ tools to integrate the speakers to the room. In many ways, they have already decided that it sounds good enough and the uncertainty as to whether there is anything more to gain, in terms of sound quality, is too great. It is a shame and in my experience with DSP/EQ tools, there is much more to be gained.

Some argue against such a solution because they have experienced that DSP/EQ actually degrade the overall sound. DSP/EQ are only tools and all types of tools have their strengths and weaknesses. If you use FIR filter with an automated process, you must take that into account in how you set it up and how you use it. As with all tools, it's mostly about the person behind the levers, that is the stopping block not the tool itself. The best programs with FIR are powerful tools with quite a few more options, that allow the user to tailor the speakers to the room, than than standard IIR EQ. However, this also greatens the potential for errors.

In the types of systems we are discussing here, we must think holistically in order to get the most out of the potential.
Let's take two seconds and think that you would have actually gotten better sound with a FIR-DSP/EQ solution and pro sound card.
You don't want this because:
- the box is perhaps uglier.
- you must use a PC.
- you use analog sources.
- you have not heard good DSP/EQ implementations.
- it is too complicated.

This is a choice only you can make, but in my mind it is a poor prioritization, if optimal sound quality is important to you.

Hello schlager

I am not sure I agree with your assessment. People are in this hobby at different depths from a technical standpoint. Some people love to DIY and others won't go near it or have tried and not gotten results they were not happy with.

There are many who don't have the backround or inclination. Doesn't make them lazy or determine if they want "optimal" sound quality or not.

It's just not for them.

Rob

 

With DSP applied, you are certainly no longer listening to an analog source. You’ve lost all that makes an analog source unique and, from my listening tests, superior to a digital source.

Room correction is best done by actually physically correcting the room, not adding DSP - it’s never going to be as good as actually fixing the problem(s) at the source. Again, we are talking about ‘what’s best’ — and what’s best is certainly not DSP.

That said, if you want a faster solution and you feel DSP sounds better than no DSP, then you’ve achieved your goal and you should be happy and enjoy the music!

 

What does this mean in practice, given that we cannot decode the "correct point of reference" of the recording without playing it back on a stereo system? Once we are back to the stereo replay doesn't neutrality become wholly subjective?

Well, it kind of involves Toole´s infamous "Circle of confusion" as we can not know how it sounded in the studio, as nothing is calibrated against standard. In other words, there is no standardisation for studio recordings. Strangely enough, the music and film industries are completely opposite. Film sound is based on calibration against standards, so that the sound you hear in your local cinema roughly matches what was approved in the studio. The same applies to image reproduction in cinemas and TV. There is a standard for color reproduction, and then you can measure, calibrate and assess against this. Luckily, we have some standardisation for hi fi stereo, starting with the old german DIN 45500, later replaced with DIN EN 61305. A rough guideline could be +/- 4 dB from 40-16000 hz.

• On neutrality:
This is a fairly generally accepted fact. There is a lot of research on this, and for this purpose many test studies have been carried out with what must be called a representative sample. There is not a single serious study that gives any credit to the claim that neutrality is a very subjective matter.

All setups have different types of errors. These errors vary in nature and size, and for some certain types of errors are completely unproblematic, while for others there are other types of errors that are unproblematic. Preferences/subjectivity are about the mistakes we can accept, but that is not the same as wanting or needing these mistakes.

Neutrality is what creates the positive experience, while errors are what destroys it to varying degrees. In other words, preferences are solely about what destroys the good experience, not about what creates it.

I want to strike a blow for objectivity/neutrality in a hobby that is otherwise subjective to the perverse. Many suffer from somewhat skewed preferences because they have been exposed to defects in sound reproduction over time.

 

With DSP applied, you are certainly no longer listening to an analog source. You’ve lost all that makes an analog source unique and, from my listening tests, superior to a digital source.

This is a choice only you can make, but in my mind a poor prioritization if sound quality is important to you.
Things have their explanation. One cannot generalize about DSP based on some experiences. It is about how it is used and how the component measures.

For DSP it is entirely possible for both the user and the designer to affect the sound negatively, but we must not fall into the trap of thinking that DSP is something "more bad" than analogue signal processing. Hang-ups do no one any favors, the best thing is to find out about things and especially to find out why things happen BEFORE you start drawing conclusions.

DSP is here to stay, but must be used correctly

 

This is a choice only you can make, but in my mind a poor prioritization if sound quality is important to you.
Things have their explanation. One cannot generalize about DSP based on some experiences. It is about how it is used and how the component measures.

For DSP it is entirely possible for both the user and the designer to affect the sound negatively, but we must not fall into the trap of thinking that DSP is something "more bad" than analogue signal processing. Hang-ups do no one any favors, the best thing is to find out about things and especially to find out why things happen BEFORE you start drawing conclusions.

DSP is here to stay, but must be used correctly

It's not a subjective generalization: DSP is definitely worse because it is an additional layer of processing. There is no "analog processing" in a properly designed world-class music system. Converting the original signal, not once, but twice, into a format that degrades the sound, is not debatable that it makes things worse.
But -- if it saves time and money as compared to a more optimal design, then it can be worth it. But DSP is never going to be the ingredient in world-class system.

 

Digitalis is indeed an interesting phenomena.

 

DSP is more or less everywhere in today's music world, so to object to its use in the playback chain of something that is already digital is almost just silly. Then it is up to everyone how they want to benefit from it. In a way, it's a bit in the same way as all the discussions against tone controls a few decades ago. You see that some have changed their minds about this as well.

 

It's not a subjective generalization: DSP is definitely worse because it is an additional layer of processing. There is no "analog processing" in a properly designed world-class music system. Converting the original signal, not once, but twice, into a format that degrades the sound, is not debatable that it makes things worse.
But -- if it saves time and money as compared to a more optimal design, then it can be worth it. But DSP is never going to be the ingredient in world-class system.

Hello

There is no analog signal processing in a world class system??? So vinyl is out??? What do you think the RIAA curve is where the signal has EQ applied at the cutter head and restored in the preamp?????

That's funny on the whole as just about everything produced today is recorded digitally so essentially all modern source material has been corrupted through the use of DSP in production.

Rob

 

Do you consider the "dryness" some people subjectively hear from some solid-state electronics to be a "single factor"? To be a "coloration"?

As compared to a tube amp? No, that "dryness" would be the absence of high amounts of 2. and 3. order harmonic distortion, which tube amps has in spades. Also most tube amps have poor damping factor, so it will have a mild eq effect following the speakers impedance, and most speakers have a rising impedance at the cross over from the midrange to the tweeter around 2-3 khz, giving a bit of boost in that area, which could be perceived as "less dry". So no, a well made SS amp, should have none or at least very little coloration.

 

Did make a video, sounds a bit strange on the playback.

 

With DSP applied, you are certainly no longer listening to an analog source. You’ve lost all that makes an analog source unique and, from my listening tests, superior to a digital source.

Ah, as they say: the plot thickens Well, do you believe it's a generally accepted stance here at What Best Forum that an analogue source and overall pathway is necessarily superior to a (partially) digital ditto? You did stress "from my listening tests," so at least it would seem you're speaking from a personal perspective mainly and hereby implicitly acknowledges that others may disagree on this, and that an absolute call on whether one or the other source format comes out on top could be up in the air. I certainly find great listening experiences can be had from either, while also admitting I've hardly heard the best that each "camp" has to offer.

In any case I find it's less constructive to shortchange a discussion essentially saying "analogue is best - period, end of story," while making it appear that stance is sanctioned by this forum as a mantra almost and that only certain predefined truths on source material, etc. are accepted when talking about "what's best." To my mind this place is about what stimulates talking about what's best within every avenue of paths taken, be they analogue or digital or whatever is discussed, and that there are no restrictions to the lofty goals or particular (and creative) approaches taken to get there. I myself have a fully active setup that's comprised of an odd mixture that spans everything from high-end products, pro segment studio, PA and cinema gear, DIY, PC-based source playback, 2nd hand and new, and a particular knack for a physically relatively unrestricted approach with speakers and power delivery (i.e.: headroom is your friend), while also being an ardent proponent of outboard active configuration. That leads to all sorts of preconceived and judgemental notions from many an audiophile about what I'm doing essentially comes down to "blast your head off SPL's," but we'll take that discussion - if interested - at another time down the road.

Room correction is best done by actually physically correcting the room, not adding DSP - it’s never going to be as good as actually fixing the problem(s) at the source. Again, we are talking about ‘what’s best’ — and what’s best is certainly not DSP.

Again, context is key. Myself I'm not using digital room correction (sorry, @schlager), but it may well be (re-)implemented in some sparing form at a later juncture in a FIR-iteration. While my acoustic environment, acoustically, could be even further tweaked, I'm fairly happy with how things are now with the measures I've taken. I like my acoustics to err slightly on the lively side rather than the opposite, and moreover am quite weary about the use of absorption - or certainly using too much it. Had I played at significantly elevated SPL's then the reverberative nature of my listening-/living room would have to be brought down a bit, incl. more extensive use of absorption.

That said, if you want a faster solution and you feel DSP sounds better than no DSP, then you’ve achieved your goal and you should be happy and enjoy the music!

What I am using my DSP unit for is crossover duties actively (sans any passive crossover parts), and with the options here offered it makes particular sense in conjunction with horn-based main speakers and subs wrt. delay, slope steepness, notch placement and peak suppression precision, and other. Indeed, my mention of DSP is linked implicitly in the context of an actively configured approach, and with horn-based speakers it's a shoe-in. Good luck implementing horn speakers passively and analogue only - I'm sure it can and has been done sounding very, very good, but what a DSP-based, active approach can do instead is potentially bringing it a step further sonically. DSP is not a quicky, so-so solution here; it's about having the better tools at hand - on the fly, at the listening position - for proper implementation.

 

Neutrality is what creates the positive experience, while errors are what destroys it to varying degrees. In other words, preferences are solely about what destroys the good experience, not about what creates it.

I like how you wrote the above. In my mind this statement can be applied to a goal and not favoring methods.

Just curious: given your stand on dsp, I wondered if you were to listen to any analog source ( vinyl or magnetic tape ) would you want to use dsp for the required source eq?

 

@schlager May I ask you another theoretical question?

If ( as it seems to be ) you are listening exclusively to digital files for music source, would you consider an audio system that is simplified down to a digital 'player' with volume control output as a digital signal to pro sound amps with onboard dsp and nothing in between ( except say a Dante interface if that's the chosen connection form ) to be a good option?

From reading your posts you use mini dsp, I can't remember the dac, and then various SS amps so this is more a question on 'packaging', and maybe on reducing digital transfer points versus anything new in signal path.

 

That's funny on the whole as just about everything produced today is recorded digitally so essentially all modern source material has been corrupted through the use of DSP in production.

But is that a reason to add more?

I personally have very little experience with DSP in any form. Does the quality of the digital components even matter ? Schlager has stated previously, in his thread, his opinion on the subject, and I respect it (though personally I am exploring a diametrically opposed approach). These types of presentations are what makes this forum interesting. If everyone agreed on a unique approach it would be boring!

 

But is that a reason to add more?

I personally have very little experience with DSP in any form. Does the quality of the digital components even matter ? Schlager has stated previously, in his thread, his opinion on the subject, and I respect it (though personally I am exploring a diametrically opposed approach). These types of presentations are what makes this forum interesting. If everyone agreed on a unique approach it would be boring!

Hello hopkins

The crux of my reply was that no SOTA What's Best system should have Analog/signal processing as compared to DSP. I pointed out that RIAA EQ is exactly that. It is analog signal processing that is required for LP playback and every system that has a turntable has to use it.

Tone controls are signal processing. A balance control is signal processing as is a stereo/mono switch.

Should we add more?? Depends on how transparent. In a perfect world we wouldn't have to contend with room modes.

Should we live with them or try to improve the situation. I choose to only use room EQ if I feel it is a necessity. Me old school analog.

I think it's rather funny that many seem to forget we did "room correction" with analog EQ typically 1/3 octave cut only. Sometimes 1/6 octave bass range. This is based on how we hear and not in anyway room specific corrections and are crude at best but acceptable results can be achieved.

With digital there is a decided improvement WRT the ease of creating filters that are room specific as far as Q, center frequency. and amplitude. There is no denying DSP for room EQ is a leaps and bounds improvement over traditional analog equivalents.

Everyone has to decide what's right for them. DSP is not a dirty word just a newer more precise tool.

Rob

 

But is that a reason to add more?

I personally have very little experience with DSP in any form. Does the quality of the digital components even matter ? Schlager has stated previously, in his thread, his opinion on the subject, and I respect it (though personally I am exploring a diametrically opposed approach). These types of presentations are what makes this forum interesting. If everyone agreed on a unique approach it would be boring!

Remember what a DSP potentially replaces rather than being an addition per se (more an that later).

If you're using an existing, passively configured speaker setup and want to implement digital room correction via a DSP, then yes you're adding a processing layer in the digital domain. Evaluating its influence as such should be done with actual listening, which goes without saying, and then assessing whether its corrections, ultimately, are a worthwhile takeaway on the whole, but also if the means itself to do so (i.e.: the DSP and its corrections) are suspected to introduce a negatively perceived "processing imprinting."

I believe these two areas of evaluation could easily get mixed up; habitual exposition to the sound of one's setup over time can easily lead one to believe what's heard is, flaws and all, still a relatively "correct" representation of the recorded material or what is otherwise deemed fairly authentic. Or, simply that you've grown to like it for what it is in a more general fashion. The DSP-corrected sound at first then may seem a bit "strange" or boring even, if nothing else simply because it sounds.. different, now that obvious peaks and dips and possible timing issues have been smoothed out. Giving it a bit more time however the realization may seep in that what's heard with the corrections isn't that bad after all, but the real eye-opener may arise from giving it a week or so and then returning to the sound sans corrections - that's when it may dawn on you that you've lived with a sound that was flawed in vital areas.

It may also be that you've managed to bring about a sound from your setup with no means of digital correction whatsoever that's fairly "flat" and smooth and with no obvious timing issues. In such a case adding a DSP for digital room correction is likely just an unnecessary layer of processing. And yet from what I can assess, achieving this in the analogue domain to a degree that equals what a DSP is capable of would be no small feat in itself, and depending on one's specific setup - the combination of speakers and listening room in particular - it is nigh on impossible even. That's not necessarily to say you'd ultimately favor the DSP-corrected sound, even over time, and whatever the reasons for this it must always come down to that in the end: whatever you prefer after having given each approach its due time from thorough evaluation, is that which you prefer.

If assessing DSP however mostly or even exclusively comes down to mere assumptions and/or conjecture - that is, with no real hands-on experience to speak of - then it's time to instead open up about its possibilities a la giving it the benefit of the doubt, or try it out for oneself to get to know what it's all about. I'm guessing lack of experience and varying degrees of conjecture with regard to the use of DSP, in whatever function, is a predominant factor here..

Lastly, a DSP can alone replace a passive crossover as a digital, active ditto. This way it's placed prior to amplification which then requires additional amps to power each driver section directly. Used as such it brings with it some obvious advantages, not least of which is seeing the passive crossover removed between the amp and drivers. I may receive some flak for stating this, but I'd go so far to claim that whoever believes a passive crossover is the lesser evil compared to using a DSP sans passive crossover (and additional amps) for direct amp-driver control, hasn't heard a properly DSP-implemented, active setup to know the difference. Whatever impediments may be introduced with conversion steps involved in a DSP to my ears clearly is the lesser evil compared to the negative effects of passive crossovers, but that's just me.

 

I am not sure I agree with your assessment. People are in this hobby at different depths from a technical standpoint. Some people love to DIY and others won't go near it or have tried and not gotten results they were not happy with.

Sure, and that is a point I have made clear before in this thread. For various reasons people don't want DSP/EQ in their system, but as in life in general, there are consequences for the choices we make. For me that choice is easy and logical. But to grab the bull by its horns, I challenge anyone to show me an in-room measured impulse response, that does not need some serious cleaning up. That is basically my point, when I'm "promoting" EQ/FIR.

 

DSP is a “Band-Aid” and shortcut to achieve goals that can be achieved without DSP. The question becomes how much time, talent, and resources, does one have to achieve these goals without DSP? In a budget-friendly system, DSP is fine and a welcome improvement.

I touch that in post 63.
The "logic" from people with expensive equipment goes something like this...

"objectivists are jealous because we can’t afford or are unwilling to buy expensive equipment, or that our systems are not expensive enough to resolve the differences, that people with expensive equipment hear.

I regard products dis-passionately; I rather ask ‘what is it, what is its nature’. It seems obvious that expensive audio equipment falls into the luxury goods category. They can have good measurements and be nicely packaged but not necessary audibly better. You could argue that expensive audio equipment give enjoyment of ownership, are build to last or provide better service, but I don't find that as a given. In the end, it really is important to learn to distinguish between actual measured performance and marketing blurb and bragging rights."

My question to you would be, have you ever measured your in-room frequency response? Of course, one should not ignore the fact that you can actually have a good impulse and frequency response in your room? But I allow myself to doubt this, as it belongs to the rarities. So the skepticism will remain, until you can present some measurements from your room. If you dare?