So are there any options if one doesn’t want to use DSP?
Beyond physically moving the mid and tweeter to try to compensate for the path length of the folded low frequency horn and/or filter effects on timing?
Some Tannoy use an all-pass in the filter network for time compensation as I understand it.
However, that seems to be a very small adjustment as compared to trying to time align the LaScala horns. Maybe its not even possible. I certainly don’t have the skill or knowledge to even try to create such a filter.
So then we just live with it if we don’t want to use DSP or try to physically compensate?
Beyond physically moving the mid and tweeter to try to compensate for the path length of the folded low frequency horn and/or filter effects on timing?
Some Tannoy use an all-pass in the filter network for time compensation as I understand it.
However, that seems to be a very small adjustment as compared to trying to time align the LaScala horns. Maybe its not even possible. I certainly don’t have the skill or knowledge to even try to create such a filter.
So then we just live with it if we don’t want to use DSP or try to physically compensate?
Your comments above indicate that you likely haven't heard the difference between time alignment/phase flattened response and what it sounds like with its stock passive crossover filters. It's not close.
The corrected (DSP crossover) sound quality is extremely neutral, while the passive version has a bit of a "whang" to the sound quality, i.e., it doesn't sound neutral. But more than that, the DSP corrected version sounds more "together", the soundstage is bigger, it has more apparent bass (subjectively), better clarity and snap, and is much smoother sounding as a result of musical harmonics not leading their fundamental frequencies, etc., (i.e., the harmonics are lined with the fundamental frequencies). It also has a more subjective sound quality of "listener engagement" that you don't get with the passive crossover version--especially if you've gone to the trouble of absorbing the near field early reflections within 1-2 meters of the loudspeaker positions and at the listening position(s).
Also note that there is one more issue with trying to time-align your tweeter to your midrange by physically moving the tweeter back: you get time alignment directly on-axis, but the more off-axis you go, the more the time alignment drifts off again to what you hear with the tweeter mouth fastened to the front baffle (without DSP time alignment delays). Think about it. This is just like having a good narrow-beam loudspeaker in the middle and two (or more) not so good loudspeakers (with equally narrow beams) on either side of the good loudspeaker. You can still hear that, even if you're on-axis.
So the price you pay for not using DSP and multi-amping is great, indeed. I wouldn't go back to using passives. (YMMV.)
Chris
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While I haven’t yet reached the the level of @Cask05 dsp filtering, I can confirm that getting time alignment sorted with DSP, as well as taming the horn resonances with parametric EQ takes the speakers so far beyond what’s possible with passive crossovers and moving the tweeters around that I won’t go back. I’m sure others will affirm.
That would be correct. I am a new player to the Klipsch and multi-way (horn) game. As a matter of fact, I’ve avoided it for years due to all of the complexities associated with crossovers and multi-way systems.
I instead chose to investigate fullrange/wideband solutions in various scenarios. The most complex of which simply integrating some sort of bass support below 150-300Hz with a subwoofer or dipole bass. Most of my projects utilized the simple adjustments by ear offered by a subwoofer’s analog plate amp or the use of a First Watt B5 electronic crossover.
I have tried using a MiniDSP for the same purpose, but only in the most basic sense of setting crossover points and choosing slopes. No EQ or time delay. My experience was that the sound quality was disappointing with the highly sensitive drivers I was using in front horns and on open baffles. The noise floor was obviously high and the sound quality poor. This was an early MiniDSP 2x4…not HD.
I did more recently figure out how to set up a Hypex amp in the most basic manner to drive my bass support. I was happy with the results.
I only ever explored the most basic testing with a UMIK and REW to see what the basic response abilities of various drivers were in my systems.
I have no real in-depth understanding of the topics of phase coherence and many other issues in speaker design.
I didn’t want my comment to be interpreted as me
dismissing DSP as an inferior or undesirable approach to this set of issues.
I have personally found the learning curve too steep, the software unintuitive and my patience lacking.
Technology is supposed to make complex problems easier to cope with right?
I think the root of the problem may be not fully understanding what I want it to do to begin with…but these other issues just make matters worse.
Add to that this baggage. The best sounding recordings I have personally experienced in all of my systems have always been analog.
I have to revert back to the adage Keep It Simple Stupid.
I will have to begin my journey in the simplest way I can. That will most likely entail me recapping a pair of used HIE crossovers I purchased into AAs. At least I’ll have a reference 😉
I have been working on my LaScalas for a while now and just recently made two big changes: I am passively bi-amping them and I have physically time-aligned the tweeters with the squawkers.
I have a good digital front end ( PSAudio PerfectWave) and with the right data it is almost at the level of my turntable. The recent high resolution transfers of the classic Blue Note recordings are very listenable and as long as I don't break out one of my original vinyl discs the convenience is mostly worth it. CDs, on the other hand or CD resolution files are not really in the same league. I have thought about something like the Dayton Audio DSP-408 but I don't want to turn my high resolution files and thousands of records into CD quality data.
Just last night I redid my search and found there is now a miniDSP 2x4 HD available that runs at 96kHz. Not the 192kHz of the best stuff but a BIG step up from 44kHz.
My inclination would be to run the bass horns with the passive crossover and the line level 1000Hz low-pass filter that I'm currently using and then use the two channels of the miniDSP for the squawkers and tweeters. I would need two more channels of amplification but I have plenty, lol!
Has anyone used the HD version and/or compared it with the standard res version? Any other thoughts?
Pete
https://www.minidsp.com/products/mi...9hGLMwsqryRW68m7feaqJHYMjJqqwdpBoCCasQAvD_BwE
I have a good digital front end ( PSAudio PerfectWave) and with the right data it is almost at the level of my turntable. The recent high resolution transfers of the classic Blue Note recordings are very listenable and as long as I don't break out one of my original vinyl discs the convenience is mostly worth it. CDs, on the other hand or CD resolution files are not really in the same league. I have thought about something like the Dayton Audio DSP-408 but I don't want to turn my high resolution files and thousands of records into CD quality data.
Just last night I redid my search and found there is now a miniDSP 2x4 HD available that runs at 96kHz. Not the 192kHz of the best stuff but a BIG step up from 44kHz.
My inclination would be to run the bass horns with the passive crossover and the line level 1000Hz low-pass filter that I'm currently using and then use the two channels of the miniDSP for the squawkers and tweeters. I would need two more channels of amplification but I have plenty, lol!
Has anyone used the HD version and/or compared it with the standard res version? Any other thoughts?
Pete
https://www.minidsp.com/products/mi...9hGLMwsqryRW68m7feaqJHYMjJqqwdpBoCCasQAvD_BwE
@PeteAugello
The MiniDSP 2x4HD has been out for a while. It’s a significant improvement over the older non-HD version. MiniDSP has introduced their Flex line that you might want to look at. The Flex line is newer than the 2x4HD, offers a variety of inputs and outputs, and has more outputs.
I started with a 2x4HD to integrate my subwoofers with my La Scalas. I subsequently tri-amped my system )La Scalas and 2 subwoofers) using a Flex Eight DL. I documented my tri-amping journey in this thread:
https://audiokarma.org/forums/index...alas-and-using-an-active-dsp-network.1037354/
I was very happy with the 2x4HD. I’m very pleased with the Flex Eight DL.
The MiniDSP 2x4HD has been out for a while. It’s a significant improvement over the older non-HD version. MiniDSP has introduced their Flex line that you might want to look at. The Flex line is newer than the 2x4HD, offers a variety of inputs and outputs, and has more outputs.
I started with a 2x4HD to integrate my subwoofers with my La Scalas. I subsequently tri-amped my system )La Scalas and 2 subwoofers) using a Flex Eight DL. I documented my tri-amping journey in this thread:
https://audiokarma.org/forums/index...alas-and-using-an-active-dsp-network.1037354/
I was very happy with the 2x4HD. I’m very pleased with the Flex Eight DL.
So...upon reading another forum's thread on zeroth order crossover filters, it seems as if someone else has given them an honest try. Apparently these people are hearing the same things that I reported on in another forum thread.
I'm not trying to crash the party at akarma, but I believe that if anyone else was interested in "zeroth order" crossover filters that further flatten the overall phase (without having to use FIR filtering), what these guys have to say in that thread should be worth your time--perhaps enough to try it yourself.
Note that having full-range directivity control and control of early reflections within the first ~3 feet (1m) from the horn mouths is really one of the prerequisites of hearing this dramatic change in overall sound quality (albeit one that's difficult to describe easily).
So if you're using hybrid loudspeakers having direct radiating woofer(s) which lose directivity control horizontally below at ~800 Hz (for a single 15" woofer), the ratio of direct/reflected energy of your net sound field arriving at the listener's ears is much lower than if using a fully horn loaded loudspeaker--such as a La Scala, Belle, K-horn, Jubilee (both types) or perhaps MWM, as well as a small handful of other manufacturer's horn-loaded bass bins (and DIY clones of any of these designs). Otherwise, you're looking at having to approximate a live-end/dead-end studio with lots of absorption in the front of the room by the loudspeakers in order to control their early reflections in-room.
___________________________________________________________________
By the way, someone mentioned in the akarma thread that I have trouble with my Jubilee bass bins with phase. I just wanted to comment on this: I don't own a pair of "Heritage Jubilees" (i.e., 2nd-Gen Jubilees) that have internal reflex porting (i.e., the back chamber on the woofers is ported to the front chamber--which just happens to be at the throat of the horn)--instead I own a pair of 1st-Gen Jubilees (since 2007). The measurements that you see in another thread on this forum of the 2nd-Gen bass bin phase growth are of another person's loudspeakers, not mine.
In fact, one of the reasons why I mentioned this was to highlight the tradeoff between the 1st-Gen and 2nd-Gen bass bins: that extra octave of extreme low end performance of the 2nd-Gen bass bins comes at a significant price (and not just a 5x increase in loudspeaker pricing). It includes a large weight growth, a larger size, having to deal with MDF instead of plywood (a longer term durability issue, especially in a loudspeaker that's so heavy and large), and in terms of bass phase growth, which is audible. I instead recommend looking at the 1st-Gen bass bin with a TH-SPUD-like pair of horn-loaded subwoofers placed just behind each Jubilee in a room corner (if you've got room corners available), thus splitting the size of the 2nd-Gen bass bin into two parts (and with considerable cost savings), avoiding not only the phase growth of reflex ports but also breaking up the deep bass response below ~40 Hz into two parts, which also limits modulation distortion and even harmonic distortion (i.e., the SPUDs actually have lower distortion than the 2nd-Gen bass bins below 40 Hz).
As someone else mentioned: it seems to just keep getting better and better...as the transfer function of the loudspeakers approaches flat amplitude and phase response at the listener's ears. Try it for yourself.
Chris
I'm not trying to crash the party at akarma, but I believe that if anyone else was interested in "zeroth order" crossover filters that further flatten the overall phase (without having to use FIR filtering), what these guys have to say in that thread should be worth your time--perhaps enough to try it yourself.
Note that having full-range directivity control and control of early reflections within the first ~3 feet (1m) from the horn mouths is really one of the prerequisites of hearing this dramatic change in overall sound quality (albeit one that's difficult to describe easily).
So if you're using hybrid loudspeakers having direct radiating woofer(s) which lose directivity control horizontally below at ~800 Hz (for a single 15" woofer), the ratio of direct/reflected energy of your net sound field arriving at the listener's ears is much lower than if using a fully horn loaded loudspeaker--such as a La Scala, Belle, K-horn, Jubilee (both types) or perhaps MWM, as well as a small handful of other manufacturer's horn-loaded bass bins (and DIY clones of any of these designs). Otherwise, you're looking at having to approximate a live-end/dead-end studio with lots of absorption in the front of the room by the loudspeakers in order to control their early reflections in-room.
___________________________________________________________________
By the way, someone mentioned in the akarma thread that I have trouble with my Jubilee bass bins with phase. I just wanted to comment on this: I don't own a pair of "Heritage Jubilees" (i.e., 2nd-Gen Jubilees) that have internal reflex porting (i.e., the back chamber on the woofers is ported to the front chamber--which just happens to be at the throat of the horn)--instead I own a pair of 1st-Gen Jubilees (since 2007). The measurements that you see in another thread on this forum of the 2nd-Gen bass bin phase growth are of another person's loudspeakers, not mine.
In fact, one of the reasons why I mentioned this was to highlight the tradeoff between the 1st-Gen and 2nd-Gen bass bins: that extra octave of extreme low end performance of the 2nd-Gen bass bins comes at a significant price (and not just a 5x increase in loudspeaker pricing). It includes a large weight growth, a larger size, having to deal with MDF instead of plywood (a longer term durability issue, especially in a loudspeaker that's so heavy and large), and in terms of bass phase growth, which is audible. I instead recommend looking at the 1st-Gen bass bin with a TH-SPUD-like pair of horn-loaded subwoofers placed just behind each Jubilee in a room corner (if you've got room corners available), thus splitting the size of the 2nd-Gen bass bin into two parts (and with considerable cost savings), avoiding not only the phase growth of reflex ports but also breaking up the deep bass response below ~40 Hz into two parts, which also limits modulation distortion and even harmonic distortion (i.e., the SPUDs actually have lower distortion than the 2nd-Gen bass bins below 40 Hz).
As someone else mentioned: it seems to just keep getting better and better...as the transfer function of the loudspeakers approaches flat amplitude and phase response at the listener's ears. Try it for yourself.
Chris
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@THD+N
I’m considering starting with a passive that has been worked out for me (besides an AA) like the Universal or a derivative like yours for the PRV.
Is there some tolerance for values of the components?
For instance, the 80 uF on the woofer for the LaScala. Parts express has a few options for paralleling 40uF caps, but the most affordable option would be an 82uF Crosscap or Audyn.
Most other values can be obtained by paralleling a 1uF.
I do have some caps on hand that would get me to within .5-1uF if I used them creatively in areas like the tweeter filter.
I figured mist of these caps are 5% or so, but I should ask what the margin might be?
I’m considering starting with a passive that has been worked out for me (besides an AA) like the Universal or a derivative like yours for the PRV.
Is there some tolerance for values of the components?
For instance, the 80 uF on the woofer for the LaScala. Parts express has a few options for paralleling 40uF caps, but the most affordable option would be an 82uF Crosscap or Audyn.
Most other values can be obtained by paralleling a 1uF.
I do have some caps on hand that would get me to within .5-1uF if I used them creatively in areas like the tweeter filter.
I figured mist of these caps are 5% or so, but I should ask what the margin might be?
Chrome... The component tolerance of 5% is more than adequate. Most of the Dayton caps rated for 5% come closer to <2% difference when measured. Audyn caps are a great value for the price/performance.
Even the Dayton air core coils are great for the price.
For shunt type caps (especially across the woofer), a non-polar electrolytic is all you need, not some giant film cap.
For the tweeter filter, 2.2uf is common, but the second tweeter cap can be anything from 6.8uF~7.5uF with very little penalty.
Even the Dayton air core coils are great for the price.
For shunt type caps (especially across the woofer), a non-polar electrolytic is all you need, not some giant film cap.
For the tweeter filter, 2.2uf is common, but the second tweeter cap can be anything from 6.8uF~7.5uF with very little penalty.
I assumed the 5% tolerance was adequate.
My question was more directed at whether or not substitution of an 82uF in place of the 80uF on the woofer would cause any problems.
They have an 80uF non polar electrolytic. It is rated at 100V. Would that be sufficient?
It is very difficult to choose between the variety of caps available, grades etc.
I don’t like the idea of paying premium prices for pretty wrappers…and they are pretty.
I was considering a combination of Jantzen Crosscaps, Superiors and a few Silvers. They add up fast.
The cheapskate/skeptic in me wants to order all Dayton caps. I’d go for the precision 1% where available. 🤷♂️
I’m not good with choices…too much OCD.
My question was more directed at whether or not substitution of an 82uF in place of the 80uF on the woofer would cause any problems.
They have an 80uF non polar electrolytic. It is rated at 100V. Would that be sufficient?
It is very difficult to choose between the variety of caps available, grades etc.
I don’t like the idea of paying premium prices for pretty wrappers…and they are pretty.
I was considering a combination of Jantzen Crosscaps, Superiors and a few Silvers. They add up fast.
The cheapskate/skeptic in me wants to order all Dayton caps. I’d go for the precision 1% where available. 🤷♂️
I’m not good with choices…too much OCD.
Don't get overwhelmed by choices. The Dayton or Audyn polypropylene caps are perfectly fine for just about any build. Even though they are on the cheaper end of the scale, they are great caps.
The boutique caps may give you a little extra something, but you may want to explore those options after you dialed in other things first.
Again, if you decide to go with Dayton or Audyn, the 5% ones are good. No need to pay more for 1% when the 5% are almost 1%.
82uF is close enough to 80uF for the woofer.
The boutique caps may give you a little extra something, but you may want to explore those options after you dialed in other things first.
Again, if you decide to go with Dayton or Audyn, the 5% ones are good. No need to pay more for 1% when the 5% are almost 1%.
82uF is close enough to 80uF for the woofer.
When I first started reading forums many years ago, a lot of the advice I was reading did not make sense. I quietly lurked and respected the opinions of others, but you have to be careful with opinions and advice. I usually would try something that someone advised against and in a lot of cases, there were no negative effects. Caps is one of those avenues.
We all hear differently and someone who uses Dayton caps versus a Jupiter cap might say WOW, i can hear a difference. Someone else might say, $hit, that was a waste of money.
We all hear differently and someone who uses Dayton caps versus a Jupiter cap might say WOW, i can hear a difference. Someone else might say, $hit, that was a waste of money.