Changing a tweeter good idea on a manufactured speaker?

[guy soundy]

I have a B&O Beovox S45-2 and while I do like the sound, I do feel it could be a bit better. Lately I've heard an AMT tweeter and absolutely love how it sounds. So I was wondering if it is a good idea to swap the dome one for a AMT? (of the same size of course).

 

[Rick Sykora]

If the speaker is a good design currently, you would need to have significant knowledge and equipment to have a decent shot at producing an improved, accurate speaker. Otoh, have you tried simply equalizing the current speaker?

 

[Zek]

So I was wondering if it is a good idea to swap the dome one for a AMT?

Thiele/Small parameters for both tweeters must be the same.

 

[DVDdoug]

Do you know the crossover frequency of the existing speaker?

I'd go-ahead and try it if you don't mind gambling the money and if you can do that without permanent altering the cabinet. As a test it would be OK to prop it up on top of the cabinet, but it looks like those are sealed speakers so you probably can't run wires out without un-sealing it, and that can change the bass. And I would try one first so you can A/B.

What you probably don't know is the sensitivity of the existing tweeter so the replacement may have higher or lower output. Ther may also be a resistor "pad" on the crossover and you can bypass that if there is not enough output from the new tweeter, or you could add resistors if the output is too high. If you want to look into that, you'll need to draw-out (and figure-out) the crossover. Or if you are lucky there may be a schematic stapled inside...


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I'm probably going to change the (paper cone) tweeters on a pair of cheap no-name speakers that somebody gave me. These are 2-ways with 8-inch woofers and before I owned them I had already changed (and "upgraded") the woofers because the old ones had rotted foam surround (the new ones have "solid" rubber). But they ARE cheap no-name speakers...

 

[Robin L]

It won't work. Speaker design requires a lot of design knowledge and access to exactly the right parts. If you have to ask the question, then you're probably not qualified to make the attempt.

 

[dartinbout]

Interesting topic, as I'm due to receive a set of Paradigm Signature S4 beryllium tweeters as a trade for my Paradigm Studio S4 tweeters. Per the provider, the crossover is the same. The opportunity to do an in place upgrade, within the same family, seemed like an attractive, somewhat, linear cost effective move. If they tap into my brain's music chemistry, I might do the same for the family's center and surround channels.

 

[tecnogadget]

If you have to ask if it’s a good idea…probably isn’t a good idea

 

[Doodski]

If the OP was to bypass the crossovers and then use a different tweeter with a active system design he could pull it off without extensive knowledge of the principles of electric circuits.

 

[alex-z]

I have a B&O Beovox S45-2 and while I do like the sound, I do feel it could be a bit better. Lately I've heard an AMT tweeter and absolutely love how it sounds. So I was wondering if it is a good idea to swap the dome one for a AMT? (of the same size of course).

The AMT tweeter by itself does not have a particular sound. What you hear from a loudspeaker is a culmination of the frequency response and radiation pattern, you can build two designs, one with an AMT, another with a dome tweeter, and tune both to sound the exact same.

There are these myths about low driver mass for better transient response, those people don't understand how speakers work. A driver with a higher mass is capable of achieving the same transient response and peak SPL if the motor strength is high enough. Motor strength is mostly just a matter of money, a bigger magnet and larger voice coil.

Any driver swap has the potential to make the speaker sound better or worse. Depends on how well the new driver integrates with the crossover, and if the original design was any good. Looking at the original Beovox S45-2 crossover, I see it only has a first order band-pass on the mid-range driver. Shallow slopes like that rarely sound good, often compromising the distortion and radiation pattern of a speaker for the sake of cost savings. A crossover redesign is likely to help far more than a new tweeter, but that is a skilled and laborious undertaking.

 

[GXAlan]

The tweeter is less sensitive to enclosure than the woofers, which allows more forgiveness when swapping. The key is matching the sensitivity (db/w/meter) of the original, or having an L-pad or resistor to attenuate as appropriate. You also have to make sure the crossover is high enough so as not to blow the new AMT tweeter.

 

[Chromatischism]

It is definitely not worth it. Not only would a good dome tweeter do just as well, like everyone else said, there's no good way to integrate it into the speaker design without other changes, knowledge, and measurement gear.

 

[Chrispy]

Just tuning in to see if it worked well or not...but I'd probably not bother in the first place.

 

[guy soundy]

Just tuning in to see if it worked well or not...but I'd probably not bother in the first place.

I am not going to do it yet, just asking first hand, also I am going to let someone else do it IF I decide to let it be changed

The tweeter is less sensitive to enclosure than the woofers, which allows more forgiveness when swapping. The key is matching the sensitivity (db/w/meter) of the original, or having an L-pad or resistor to attenuate as appropriate. You also have to make sure the crossover is high enough so as not to blow the new AMT tweeter.

Thiele/Small parameters for both tweeters must be the same.

How do I find that out? The tweeter in question I want the dome replaced with : https://www.daytonaudio.com/product/1166/amt2-4-air-motion-transformer-tweeter-4-ohm
here's a pic of the tweeter but I can't say what the measurements are of it.

The AMT tweeter by itself does not have a particular sound. What you hear from a loudspeaker is a culmination of the frequency response and radiation pattern, you can build two designs, one with an AMT, another with a dome tweeter, and tune both to sound the exact same.

There are these myths about low driver mass for better transient response, those people don't understand how speakers work. A driver with a higher mass is capable of achieving the same transient response and peak SPL if the motor strength is high enough. Motor strength is mostly just a matter of money, a bigger magnet and larger voice coil.

Any driver swap has the potential to make the speaker sound better or worse. Depends on how well the new driver integrates with the crossover, and if the original design was any good. Looking at the original Beovox S45-2 crossover, I see it only has a first order band-pass on the mid-range driver. Shallow slopes like that rarely sound good, often compromising the distortion and radiation pattern of a speaker for the sake of cost savings. A crossover redesign is likely to help far more than a new tweeter, but that is a skilled and laborious undertaking.

Maybe, but the domes only go to 20.000hz while the AMT's go to 22.000hz meaning it would fully cover the scientifically assured human hearing range.

 

[Chromatischism]

Maybe, but the domes only go to 20.000hz while the AMT's go to 22.000hz meaning it would fully cover the scientifically assured human hearing range.

Domes can go to 30,000 Hz (and more), but you don't hear much beyond 16,000 Hz anyway.

S400 MKII

S400 Passive Loudspeakers

buchardtaudio.com

 

[alex-z]

Maybe, but the domes only go to 20.000hz while the AMT's go to 22.000hz meaning it would fully cover the scientifically assured human hearing range.

Unless you use a tiny AMT, something similar to a 19mm dome tweeter, the radiation pattern is going to narrow substantially near 20000Hz. A smaller radiating area means a higher crossover point, which means a directivity compromise. There is no free lunch in speaker design, swapping to an AMT is just as likely to make your speakers worse as it is to make them better.

The number of people who can actually hear to 20000Hz is extremely low if you are using a normal listening level of 90dB or less. Even by the age of 25 it is rare to hear beyond 16000Hz.

 

[guy soundy]

If the speaker is a good design currently, you would need to have significant knowledge and equipment to have a decent shot at producing an improved, accurate speaker. Otoh, have you tried simply equalizing the current speaker?

Yes, but only for what the AVR allowed (delay and how far the speakers are from ear range), thing is, I had tried out a pair of Wharfdale EVO 4.2 who had these AMT tweeters and while I find the EVO 4.2 a bit too flat overall the tweeters were really great. The particular one I found (the one in one of my posts above) should cover the hole perfectly, and the AMT tweeter itself should be roughly about the same size as the dome, the only thing I can't say is what the specs are of the dome tweeter but it should be a Philips one.

 

[Rick Sykora]

Yes, but only for what the AVR allowed (delay and how far the speakers are from ear range), thing is, I had tried out a pair of Wharfdale EVO 4.2 who had these AMT tweeters and while I find the EVO 4.2 a bit too flat overall the tweeters were really great. The particular one I found (the one in one of my posts above) should cover the hole perfectly, and the AMT tweeter itself should be roughly about the same size as the dome, the only thing I can't say is what the specs are of the dome tweeter but it should be a Philips one.

Without knowing more about your AVR, that eq may not mean much for the high frequency balance.

If these speakers are nothing special and you want to try the AMT, give it a shot. However, if you are looking for folks here to condone a hack job, you have come to the wrong forum. Without knowing more about the current design and measuring its tweeter and the potential replacement, you will be shooting in the dark.

 

[guy soundy]

Without knowing more about your AVR, that eq may not mean much for the high frequency balance.

If these speakers are nothing special and you want to try the AMT, give it a shot. However, if you are looking for folks here to condone a hack job, you have come to the wrong forum. Without knowing more about the current design and measuring its tweeter and the potential replacement, you will be shooting in the dark.

Marantz SR8015, but like I said, I am not the one to do it, just wondering mostly if people here ever done such a thing and wherever how feasible it is. The only thing I am reasonably sure about is that the AMT tweeter has different sensivity (around 92 db) while the dome one is around 90 or 96 (not sure which) https://beo.zone/en/beovox-s45-2-passive-loudspeakers/

don't know if it is too much of a difference, if anyone could indentify the Philips tweeter in one of my photos I am sure it would make everything clear.

 

[polmuaddib]

So I was wondering if it is a good idea to swap the dome one for a AMT?

 

[guy soundy]

YOU UNDERESTIMATE MY INCOMPETENCE