Planning on a FAST design, I was looking around for FR 3-4” driver to work with a 300Hz high pass crossover. Got an Alpair 6.2 metal, Fostex 108EZ and Fountek FR88EX.
Dont know why, but the Fostex that has the highest efficiency also sounds the best in this application. The Alpair does not have the sparkle on top and fountek sounds thin and scratchy at the upper end with minimal warmth. Although the frequency response graphs of all the 3 drivers looks very similar on paper, I wonder why the Fostex sounds the most balance (although it will need the most attenuation in a passive design). It has the midrange warmth and also highs as good as tweeter. It also sounds the most resolved it seems to my ears.
Wonder why this is so and if the higher efficiency contributes to this apparently more “dynamic” and clear sound. So even if low power valve amplifiers are not being used, and amplification is SS only, does anyone feel that high efficiency drivers “sound” better than low efficiency ones with similar diameter and frequency response ?
Thanks.
Dont know why, but the Fostex that has the highest efficiency also sounds the best in this application. The Alpair does not have the sparkle on top and fountek sounds thin and scratchy at the upper end with minimal warmth. Although the frequency response graphs of all the 3 drivers looks very similar on paper, I wonder why the Fostex sounds the most balance (although it will need the most attenuation in a passive design). It has the midrange warmth and also highs as good as tweeter. It also sounds the most resolved it seems to my ears.
Wonder why this is so and if the higher efficiency contributes to this apparently more “dynamic” and clear sound. So even if low power valve amplifiers are not being used, and amplification is SS only, does anyone feel that high efficiency drivers “sound” better than low efficiency ones with similar diameter and frequency response ?
Thanks.
It sounds more dynamic due to upper midrange response peaks, which increases vocal clarity.
The frequency response are not close at all. I've measured them. I want to try to be politically correct, but unfortunately, the frequency response in the datasheets do not correspond with independant measurements.
The frequency response are not close at all. I've measured them. I want to try to be politically correct, but unfortunately, the frequency response in the datasheets do not correspond with independant measurements.
Last edited:
A high efficiency 2-way means early bass rolloff, which leads to the perception of an increase in dynamics and clarity.
There's no power compression in a well-designed low-efficiency speaker (85 dB/W) before it can make one's ears bleed. People making comments about high efficiency=more dynamic (as in clarity, not volume) have simply not heard a good speaker in the other camp, or are just used to a forward-tilted response curve.
I've had drivers that people claimed to be very dynamic like Fostex 8" fullrange. Which is true, it does sound very dynamic, like Grado headphones. What I've found after some digital EQ to add in some bass that it was missing, and removing the breakup peaks, is that the dynamics goes away. It sounds better, but the forward sounding midrange goes away and so does the extra clarity.
Hi, nearly all same size drivers do the same cone movement for any level, rgds, sreten.
Hi,
Your understanding of efficiency for drivers is completely wrong. There is no magic.
rgds, sreten.
Last edited:
How do you feel about Troels Gravesen's site High Efficiency Speakers
where he praises high efficiency speakers eloquently despite having designed plenty of low-medium efficiency speakers in the past. He certainly seems to have a lot of experience in speaker building.
where he praises high efficiency speakers eloquently despite having designed plenty of low-medium efficiency speakers in the past. He certainly seems to have a lot of experience in speaker building.
You are in a way correct Boscoe, about lower distortion. But for a different reason as explained here ULTIMATE
It is more about the amplifier requirements to clearly reproduce a specific dynamic range during transients. For example a 120 W amp used with a 85dB/W speaker can cleanly reproduce a transient of 106 dB before clipping. OTOH a 95dB/W speaker can reproduce a transient of 116dB before clipping.
So the distortion from an amplifier is minimised by using high efficiency speakers resulting in a more "dynamic " sound as the dynamic range of the system as a whole is increased. So for a low efficiency speaker the amplifier distortion will likely become a limiting factor even before the speaker has run out of excursion.
This would also have benefits on background noise from the amplifier providing a quieter noise base to start with. In the above combination, to reproduce 106dB the HE speaker would require the amp to be delivering 16W that can be done at a lower noise than the 120W which will be needed if using the 85dB/W speaker.
Last edited:
As I see this, there are two aspects to high sensitivity speakers sounding better than low sensitivity speakers, one is the sensitivity that comes from the overall electro mechanical design, so comparing a 4" driver with 85dB/W/m to a 4" driver with 88dB/W/m, to produce the same SPL they have to sweep the same volume, because that be the physics, but the 4" driver with the greater sensitivity is less demanding of the amplifier, which I believe has sonic benefits, even before the amp goes into clipping.
The second aspect is the sensitivity that comes from increasing cone size, the 4" 88dB/W/m speaker will have to travel a lot more in and out than say a 8" 88db/W/m driver for the same SPL, which means that, if you can accept that distortion increases non linearly the further the cone moves away from the zero position, it will result in better sound. If you want to call that greater dynamics or lower distortion is neither here or there I think.
This then beautifully explains why you can buy 8 4" drivers from parts express for $10, team them with 20 cent tweeters and produce a speaker of astounding ability, or why horn speakers which introduce so many other problems sound so amazing, it's all about sensitivity.
And it also explains the cult of the 3 watt valve amplifier, it's not the amp, it the fact that they have to be used with high efficiency speakers which just naturally possess lower distortion.
The second aspect is the sensitivity that comes from increasing cone size, the 4" 88dB/W/m speaker will have to travel a lot more in and out than say a 8" 88db/W/m driver for the same SPL, which means that, if you can accept that distortion increases non linearly the further the cone moves away from the zero position, it will result in better sound. If you want to call that greater dynamics or lower distortion is neither here or there I think.
This then beautifully explains why you can buy 8 4" drivers from parts express for $10, team them with 20 cent tweeters and produce a speaker of astounding ability, or why horn speakers which introduce so many other problems sound so amazing, it's all about sensitivity.
And it also explains the cult of the 3 watt valve amplifier, it's not the amp, it the fact that they have to be used with high efficiency speakers which just naturally possess lower distortion.
Hmmm...well said.
I used to think tube based amps have some "special' thing called "fluidity"...no idea why. I do agree that tube amps do have prominent low mid range presence or "warmth" that I believe can also be added in with an inexpensive equalizer if desirable.Hmmm...well said.
You can't simulate a tube amp sound that way. You would have to increase the output impedance and add monotonically decreasing harmonics digitally. The equalization would be based on the impedance curve of the speakers. Then there are the really good tube amps that are very quick and detailed, fast transient attacks and airy treble. Those would be harder to simulate than the warm tubey stuff (which I do not like).
The tube amps do sound more dynamic, due to the rising response curve.
Anyway, the assumption you seem to be making is that lower efficiency speakers do not sound dynamic. This is not true. You have simply not heard any good ones. The 4" drivers you list in your post are simply not good speakers when run by themselves. Not even close. Listen to a Linkwitz Orion or a Peerless HDS based system, then decide.
Last edited:
Hi,
High sensitivity speakers generally have less distortion issues and less
thermal compression issues. They also tend to be more coloured.
And unfortunately physics intervenes when it come to the bass end,
they need to be big to produce decent bass extension and levels.
The optimum compromises are different for different people and
can depend a lot on the amplification chosen if it is low power,
and intelligent compromises need to made for low power.
e.g. something like :
Speaker kit 3 : Peerless SKO204 + DT105 + crossovers ! | eBay
In bix boxes like :
Tuned low, around 33Hz and used near walls / corners will make a
surprising fist of lower powered amplifiers, size and efficiency matters.
rgds, sreten.
High sensitivity speakers generally have less distortion issues and less
thermal compression issues. They also tend to be more coloured.
And unfortunately physics intervenes when it come to the bass end,
they need to be big to produce decent bass extension and levels.
The optimum compromises are different for different people and
can depend a lot on the amplification chosen if it is low power,
and intelligent compromises need to made for low power.
e.g. something like :
Speaker kit 3 : Peerless SKO204 + DT105 + crossovers ! | eBay
In bix boxes like :
An externally hosted image should be here but it was not working when we last tested it.
Tuned low, around 33Hz and used near walls / corners will make a
surprising fist of lower powered amplifiers, size and efficiency matters.
rgds, sreten.
Completely agree with you Sreten about the need for bigger boxes for the bass end for HE speakers. But not so, if active amplification (+/- equalisation) with low efficiency drivers is employed for the bass only region, allowing smaller boxes. Dynamic and unclipped reproduction is very essential in the mid-high frequencies where the ear is most sensitive, moreso than the low bass region. Hence the proposed preference of HE 4" full range drivers than the low efficiency ones.
Just a thought
Fully agree with you...that is why the listed 4" drivers are all to be used with woofer support and not to be run by themselves.
I have the 8" Seas Mag woofer of the Orion and compared it to the Fostex 208 sigma for OB designs
. Have not tried the tweeters you mention though. Could you please tell me what is so special about the Peerless HDS tweeter compared to the similar but lower priced Dayton Audio RS28A-4 . Thanks.- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.