Assume I have a pair of dream speakers, called speaker A. I don't own it but, instead, I have a similar model belonging to the same brand, speaker B.
I've been playing with simulations of two crossover circuits that are different from each other. I tried tweaking the crossover values on the simulator of the speaker B until the frequency response graph matched that of the speaker A. I know there are more than FR graph to be considered but somebody had told me the FR graph is indeed the final result of all graphs. In other words, any other graphs will affect the FR graph at the end.
Attached are FR graphs of speaker A versus modified speaker B. Note that it's my intention to create the curved/ugly FR graphs--for educational purpose.
Is it possible to make sound of speaker B similar to speaker A by duplicating the frequency response? I'd love to hear the inputs.
I've been playing with simulations of two crossover circuits that are different from each other. I tried tweaking the crossover values on the simulator of the speaker B until the frequency response graph matched that of the speaker A. I know there are more than FR graph to be considered but somebody had told me the FR graph is indeed the final result of all graphs. In other words, any other graphs will affect the FR graph at the end.
Attached are FR graphs of speaker A versus modified speaker B. Note that it's my intention to create the curved/ugly FR graphs--for educational purpose.
Is it possible to make sound of speaker B similar to speaker A by duplicating the frequency response? I'd love to hear the inputs.
Most here will answer: no.
I say: yes, but then subject to the conditions below. Just copying SPL will not cut it.
a) the clone drivers should have identical cone/dome sizes
b) the acoustic transfer functions/output for each leg should be fully identical
c) respective levels should carefully match.
d) Baffle size and driver placement should be identical.
I say: yes, but then subject to the conditions below. Just copying SPL will not cut it.
a) the clone drivers should have identical cone/dome sizes
b) the acoustic transfer functions/output for each leg should be fully identical
c) respective levels should carefully match.
d) Baffle size and driver placement should be identical.
If you mean by matching just the on-axis frequency response then that is a no.
If you mean by matching the frequency response on-axis and off-axis that is a qualified yes. Some qualifications:
- you cannot match the off-axis response by fiddling with the crossover because it changes the frequency response in all directions equally. You have to design the speaker itself to have matching on- and off- axis responses.
- we are sensitive to resonances and so you will have to match the tiny resonant bumps in the frequency response not just the smoothed frequency response.
- at higher SPLs distortion will be at audible levels (and lower in many designs) and this doesn't show up in a simple frequency response. It can be included though as additional plots of the levels of the harmonics.
Speaker A is flawed. Freqency response is not flat.
On axis should be flat. Of axis should be well behaving.
However, even if you match on axis 'flawed' response, speaker B will not sound the same. You will not be able to match of axis response.
If speaker A and B will have different of axis, they will spray the room differently. We not only listen to first arriving signal, but room as well.
How abou impulse or phase? You ignore those completely? Or you consider those do not contribute to the sound?
On axis should be flat. Of axis should be well behaving.
However, even if you match on axis 'flawed' response, speaker B will not sound the same. You will not be able to match of axis response.
If speaker A and B will have different of axis, they will spray the room differently. We not only listen to first arriving signal, but room as well.
How abou impulse or phase? You ignore those completely? Or you consider those do not contribute to the sound?
Yep, it happens a lot in prosound, particularly install, but with live too.
Makes for a more seamless sounding coverage, when up close and side speakers need to sound similar to main arrays.
Here's tool for matching speakers https://eclipseaudio.com/loudspeaker-matching/
Works pretty well.
Makes for a more seamless sounding coverage, when up close and side speakers need to sound similar to main arrays.
Here's tool for matching speakers https://eclipseaudio.com/loudspeaker-matching/
Works pretty well.
Yes, certainly so: no disagreement here.
That is why I introduced the extra conditions: same radiating area, type and same acoustic transfer function and baffle+placement on baffle.
Only then will the off axis behaviour of the original also be mimicked. Phase follows frequency as per Hilbert in the acoustic domain, so that is not the issue if the homework - not easy!- has been done well.
The box & drive unit sizes need to be roughly the same and also the crossover frequencies & slopes. You do need very close matching of frequency response. I've successfully done this with electronic EQ but its easier these days with good (there are many bad) digital EQ
What are your two speakers?
How did you do those frequency responses in #1?
What are your two speakers?
How did you do those frequency responses in #1?
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Why are you shorting out your resistors?
Otherwise, I agree with the others' sentiments.
Otherwise, I agree with the others' sentiments.
Although a frequency response graph IS a cumulative depiction of numerous things, it IS NOT all things we can hear.
In particular the various components of Harmonic Distortion, AND the attack & decay character of any given frequency.
Also, using passive components to 'shape' FR introduces phase shift changes that impact 'non-symmetrical room reflections'.
Using the term "similar sound" is really very subjective > EG. how similar is similar ???
I guess the best and most classic example is:
If we measure different speakers as 'FLAT' in an anechoic chamber, they still all sound different at home in a room.
PS.
There are still things that you seem not to grasp > but I don't know how to explain them.
Are the baffle positions of the drivers the same? Are the driver sizes the same? Looking at your sim you have no XYZ data so all in the exact same spot on the baffle? I would also look at voltage drives but if the drivers are not identical it won't be a 1 to 1 where you can just sub a different driver and expect the same FR or Polar response by the driver.
As the other posters have pointed out no free lunch!
Rob 🙂
As the other posters have pointed out no free lunch!
Rob 🙂
Possibly so he could toggle responses (easier done with Ctrl-S in VCad to "short" a component, or Ctrl-O to "open" a component). Very useful when trying leading resistor vs LPad options on a midrange or tweeter to see which one gets better phase alignment with other drivers.
It's possible to get almost identical summed frequency responses yet the speakers will sound different. With the summed only response we're missing how the individual drivers are contributing. For example XO points or phase response could be different. The midrange could be playing higher in A or B. or may be crossing to one driver in phase with a +6dB unity sum or 90 degree phase rotation leading to +3db unity sum. This will lead to different lobing, beaming / off axis behaviour and therefore we'll see that in the vertical and horizontal off axis power responses.
If the transfer functions are identical, resulting in the same individual driver slopes, then I'd say you couldn't tell them apart.
If the transfer functions are identical, resulting in the same individual driver slopes, then I'd say you couldn't tell them apart.