Yes, unless the output of the HF and mid drivers is already happens to be time aligned with whatever crossover filters and polarity choice you made.
I looked at plots (of mids) again today...I don't completely understand the phase, but it gets silly around what is closer to my crossover -- about 1.13 KHz. I don't understand why there is no expected notch at double this, or about 2.3 KHz? The big notch is about 3.4 KHz, which is almost exactly 3x my ports' tuning. I is confused 
The multiple wrapping phase trace is due to an incorrect test delay time, though I am unfamiliar with REW and don't know how to correct it, RFTM...I looked at plots (of mids) again today...I don't completely understand the phase, but it gets silly around what is closer to my crossover -- about 1.13 KHz. I don't understand why there is no expected notch at double this, or about 2.3 KHz? The big notch is about 3.4 KHz, which is almost exactly 3x my ports' tuning. I is confused
I don't understand why you would expect a notch at double the crossover frequency.
The 3.4kHz notch would indicate the top end of the mid bandpass range. It could be higher than expected due to a "kazoo" effect, the material used is not cabinet grade.
Too many moving parts
.
Soldermizer,
To zero align IR in REW to get phase right as requested below, either have present window viewed as "SPL & Phase" or "Impulse", then in "Controls" you get a button named "Estimate IR Delay" that need a push
To zero align IR in REW to get phase right as requested below, either have present window viewed as "SPL & Phase" or "Impulse", then in "Controls" you get a button named "Estimate IR Delay" that need a push
Weltersys asked: "I don't understand why you would expect a notch at double the crossover frequency."
I don't. This is one of the few things I understand about Synergy: my mid ports are sized (sloppily, granted) for about a 1KHz crossover. Even allowing for my inexact assembly, the graphs are not so different for L and R units. I see the phase get stupid around my target port and x-over (~1.1 KHz) but little to no fall-off (acoustic low pass filter, where are you?) even well into the 2K's. Phase gets stupid again around 3.4 K, making me wonder "WTF"?
Thanks guys. I've used REW for a few years but 99% with frequency. I know that to do some types of delay or impulse it needs a loopback, something I have not yet tried. Probably can do that but that is another day's soldermizing ™
Jackass mode = ON
There are many different types of adhesives usable in hobbies and the tinkerer should consider each's pros and cons. For example, based (unfortunately!) on my true experiences, hot glue on skin gives second degree burns but otherwise can be removed easily (just peel off the cooked skin!). In contrast, Gorilla Glue is a strong adhesive, appears to be very non-toxic, but if it gets on your skin expect it to stay for several days
Jackass Mode = OFF
I don't. This is one of the few things I understand about Synergy: my mid ports are sized (sloppily, granted) for about a 1KHz crossover. Even allowing for my inexact assembly, the graphs are not so different for L and R units. I see the phase get stupid around my target port and x-over (~1.1 KHz) but little to no fall-off (acoustic low pass filter, where are you?) even well into the 2K's. Phase gets stupid again around 3.4 K, making me wonder "WTF"?
Thanks guys. I've used REW for a few years but 99% with frequency. I know that to do some types of delay or impulse it needs a loopback, something I have not yet tried. Probably can do that but that is another day's soldermizing ™
Jackass mode = ON
There are many different types of adhesives usable in hobbies and the tinkerer should consider each's pros and cons. For example, based (unfortunately!) on my true experiences, hot glue on skin gives second degree burns but otherwise can be removed easily (just peel off the cooked skin!). In contrast, Gorilla Glue is a strong adhesive, appears to be very non-toxic, but if it gets on your skin expect it to stay for several days
Jackass Mode = OFF
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Thanks guys. I've used REW for a few years but 99% with frequency. I know that to do some types of delay or impulse it needs a loopback, something I have not yet tried. Probably can do that but that is another day's soldermizing ™
.....
Welcome, although in long run its fine to setup loopback mode you can just hit that "Estimate IR Delay" button and have same result, so if you happen to have post 76 mdat files saved load them again and use the button, setups having USB microhones have to live with this way to get phase right.
smartass mode= on
latex gloves are cheap (and even when using hotmelt you can rip one off your hand right quick.)
i have a "collage" of old latex gloves with several adhesive types and colors i've titled "made by hand" at the end the bench in the garage.
smartass mode=off
my first go at hot melt and foamcore taught me that scrap pieces make convenient spreader/smoothers.
latex gloves are cheap (and even when using hotmelt you can rip one off your hand right quick.)
i have a "collage" of old latex gloves with several adhesive types and colors i've titled "made by hand" at the end the bench in the garage.
smartass mode=off
my first go at hot melt and foamcore taught me that scrap pieces make convenient spreader/smoothers.
The bandpass ports top output range is determined by their size, depth, and the enclosed volume between the cone and the baffle (horn wall). From the REW screen captures you have posted, the output extends past 3kHz, the crossover could be placed anywhere below that frequency.
If your measured output differs wildly from a simulation, there are a number of possibilities that could explain the difference.
TS parameter discrepancies
VTC not correct
LTC not correct
VRC not correct
Etc. not correct
Buzzing horn walls
Measuring too close to the horn
I haven't tried WD-40 but I have tried many a solvent Realistically, small patches come off in a few hours. I did coat both hands with it when doing some forgotten project. Best you can do is wash well with soap and water, and don't touch anything for at least an hour unless you wish to be firmly glued to it That was the coating that remained for many many days.
Sent from my NV570P using Tapatalk
Realistically, small patches come off in a few hours. I did coat both hands with it when doing some forgotten project. Best you can do is wash well with soap and water, and don't touch anything for at least an hour unless you wish to be firmly glued to it That was the coating that remained for many many days.Sent from my NV570P using Tapatalk
Let's blame the T-S params since anything else would incorrectly insinuate that I could be at fault
The "mids" 4.5" full rangers I used were no-name clone drivers from a no-name clone of a 901 cabinet so it is very likely the parameters I modelled with are bogus. In any event I have a toy to play with and already I am imagining a more refined build, which in my case of course would mean the same deplorable construction techniques but with better, newer drivers
Sent from my NV570P using Tapatalk
The "mids" 4.5" full rangers I used were no-name clone drivers from a no-name clone of a 901 cabinet so it is very likely the parameters I modelled with are bogus. In any event I have a toy to play with and already I am imagining a more refined build, which in my case of course would mean the same deplorable construction techniques but with better, newer drivers
Sent from my NV570P using Tapatalk
Sit on my phase, and tell me that you love me*
Good morning boys and girls another installment in Soldermizer's twisted journey in learning (?) about "funelly things" as peteleoni called it memorably in an old post.
In a rare attempt to bring something relevant to a post, let me ask this:
"How does the Ijit (me) measure phase between drivers?" I know this has already been asked, but from reading (easier!) apparently this is no easy task, and many bogus reading can occur.
I found a cite for the "hunt the crossover" idea I mentioned earlier: In Unity Patent (#6411718), on Paragraph 7, it says more or less:
NoW, since there are some “unknown” values in the equivalent circuit [especially in the case where a Soldermizer has sloppily assembled random components ], the real
correct crossover frequency may be found. The drivers are
temporarily Wired out of phase and a frequency sWeep done.
At approximately tWice the crossover frequency one Will see
a deep notch (deep because the drivers are very Well coupled
and out of phase 180 degrees). At the notch frequency, the
drivers are acoustically 180 degrees out of phase so at half
that frequency, they Will be 90 degrees out of phase and that
is the “correct” crossover frequency based on the actual
acoustic properties.
If this is correct, does that really mean that I should use this "correct" crossover frequency instead of my intended 1000 Hz?
In some patents there are typos. One of these I claim for my works: the "comical" horn
I see in one patent Danley also covers the option of a 180 degree "horn" on an infinite baffle. Has anyone built one of them yet?
* An obscure pun on an old Monty Python song. Let's see if that one gets past the censor
Good morning boys and girls
another installment in Soldermizer's twisted journey in learning (?) about "funelly things" as peteleoni called it memorably in an old post.In a rare attempt to bring something relevant to a post, let me ask this:
"How does the Ijit (me) measure phase between drivers?" I know this has already been asked, but from reading (easier!) apparently this is no easy task, and many bogus reading can occur.
I found a cite for the "hunt the crossover" idea I mentioned earlier: In Unity Patent (#6411718), on Paragraph 7, it says more or less:
NoW, since there are some “unknown” values in the equivalent circuit [especially in the case where a Soldermizer has sloppily assembled random components
], the realcorrect crossover frequency may be found. The drivers are
temporarily Wired out of phase and a frequency sWeep done.
At approximately tWice the crossover frequency one Will see
a deep notch (deep because the drivers are very Well coupled
and out of phase 180 degrees). At the notch frequency, the
drivers are acoustically 180 degrees out of phase so at half
that frequency, they Will be 90 degrees out of phase and that
is the “correct” crossover frequency based on the actual
acoustic properties.
If this is correct, does that really mean that I should use this "correct" crossover frequency instead of my intended 1000 Hz?
In some patents there are typos. One of these I claim for my works: the "comical" horn
I see in one patent Danley also covers the option of a 180 degree "horn" on an infinite baffle. Has anyone built one of them yet?
* An obscure pun on an old Monty Python song. Let's see if that one gets past the censor
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Soldermizer - standard xo practice doesn't really apply with the synergy. I typically end up using a lpf on the mid an octave or so above the actual xo "point". I say "point" because it's really more of a blend area to get linear phase and doesn't really look like the usual acoustic slopes we're used to seeing. Even if I'm not going for lin phase I'll still use the acoustic lpf to set the xo for the mid in most cases.
The REW manual shows how to do dual channel measurements which you will need to look at the relative phase between drivers. It doesn't tell you the steps needed to get the timing right....I can help with that if/when you get there.
The REW manual shows how to do dual channel measurements which you will need to look at the relative phase between drivers. It doesn't tell you the steps needed to get the timing right....I can help with that if/when you get there.
That, or 'gap' the XO as Nate implies as is 'de riguer' with most compression horn/point source woofer alignments to account for the latter's inherent 90 deg delay.
GM
I've much to learn about x-over and phase...
Thanks guys for the pointers. I do have on hand some (RCA) y-connectors and sundry adapters It is certainly worth a try (Opportunity to TINKER WITH MY TOYS!!!) to review REW's phase and loopback procedures, also perhaps to learn about x-overs. Many questions, some perhaps not even worth investigating
(1) Is my current measurement system really a "USB mike"; I have a ECM8000 mic + Presonus Audiobox USB which is a real mic/line mixer but USB connected. I suspect this is a case of "rather than research it, why don't you just f******g try it and see if it works????"
(2) I have a vague grasp of phase (one frequency leads or lags another, the reference), and it is not the same as delay. I am still foggy on group delay and excess, minimum and wrapped/unwrapped phase (when you want to give phase as a gift ?
)
(3) Granted the Unity | Synergy is an odd case; analog x-over shifts phase 90 degrees ahead or back, other values depending on order of x-over, does this still apply with active EQ or DSP (MiniDSP)?
(4) A chamber (port) such as this design uses, is an acoustic low pass. I am still wondering how to model this in HornResp (I'm taken aback at the prospect of learning acabak ) ... and this shifts phase too ....?
Theory has its place, but experimentation is more fun. I mean, sure the military has been studying EM weapons for decades, nothing (apparently) practical has come from it, but the laser is useful for many tasks, even short of Star Trek phaser technology. But nothing will ever equal the joy of discovery a boy has upon first learning to use a magnifying glass and the Sun's rays to vaporize hapless ants
Thanks guys for the pointers. I do have on hand some (RCA) y-connectors and sundry adapters
It is certainly worth a try (Opportunity to TINKER WITH MY TOYS!!!) to review REW's phase and loopback procedures, also perhaps to learn about x-overs. Many questions, some perhaps not even worth investigating (1) Is my current measurement system really a "USB mike"; I have a ECM8000 mic + Presonus Audiobox USB which is a real mic/line mixer but USB connected. I suspect this is a case of "rather than research it, why don't you just f******g try it and see if it works????"
(2) I have a vague grasp of phase (one frequency leads or lags another, the reference), and it is not the same as delay. I am still foggy on group delay and excess, minimum and wrapped/unwrapped phase (when you want to give phase as a gift ?
) (3) Granted the Unity | Synergy is an odd case; analog x-over shifts phase 90 degrees ahead or back, other values depending on order of x-over, does this still apply with active EQ or DSP (MiniDSP)?
(4) A chamber (port) such as this design uses, is an acoustic low pass. I am still wondering how to model this in HornResp (I'm taken aback at the prospect of learning acabak
) ... and this shifts phase too ....?Theory has its place, but experimentation is more fun. I mean, sure the military has been studying EM weapons for decades, nothing (apparently) practical has come from it, but the laser is useful for many tasks, even short of Star Trek phaser technology. But nothing will ever equal the joy of discovery a boy has upon first learning to use a magnifying glass and the Sun's rays to vaporize hapless ants
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