Hi, first I want to thank the forum for the great expertise and collaboration that provides to DIY Hifi enthusiasts like myself. Second, I want to explain my system and try to get answers and feedback to my questions.
I am new to the forum however, I have been experimenting with hifi sound systems for many years. My system is 4-way with active crossover and comprises of the following:
• 2 McCauley 6174 subwoofer drivers in individual vented boxes (13.15 ft3 or 372.4 liters) tuned to 20Hz driven by a professional Carvin DCM2500 amplifier.
• 2 McCauley 6224 woofer drivers in individual seal boxes (1.337 ft3 or 37.9 liters) each driven by its own VTA M-125 Monoblock tube amplifier.
• 2 ATC SB75-150 mid drivers in the same box as the tweeters driven by its own VTA M-125 Monoblock tube amplifier.
• 2 tweeters RAAL 140-15D driven by professional Carvin DCM600 amplifier.
• NAD Preamplifier C 160.
• NAD CD player C 521i and a Linn LP12 turntable (almost ready with Audio Technica MC cartridge and step-up transformer).
• A Rane AC24 active crossover (4 way) driving all power amplifiers.
This system, although not complete in terms of upgrading amplification, sounds good (relative term) to my ears. I can clearly distinguish each musical instrument and I must admit that the mids and highs have some of the best fidelity I have heard comparing to systems that cost much more $. In addition, the 6174s from McCauley are monsters when it comes to low frequencies generation.
My issue is the bass guitar does not sound as live and as high fidelity as I expected. I think that the 6224 McCauley’s should sound more realistic and defined.
My question is what is the best (relative term) hifi 8”, 10” or 12” driver for the frequencies of 80Hz or 100Hz to 800 Hz. The crossover points in my system are 100Hz, 800Hz and 3,200Hz. Thank you in advance for your feedback.
I am new to the forum however, I have been experimenting with hifi sound systems for many years. My system is 4-way with active crossover and comprises of the following:
• 2 McCauley 6174 subwoofer drivers in individual vented boxes (13.15 ft3 or 372.4 liters) tuned to 20Hz driven by a professional Carvin DCM2500 amplifier.
• 2 McCauley 6224 woofer drivers in individual seal boxes (1.337 ft3 or 37.9 liters) each driven by its own VTA M-125 Monoblock tube amplifier.
• 2 ATC SB75-150 mid drivers in the same box as the tweeters driven by its own VTA M-125 Monoblock tube amplifier.
• 2 tweeters RAAL 140-15D driven by professional Carvin DCM600 amplifier.
• NAD Preamplifier C 160.
• NAD CD player C 521i and a Linn LP12 turntable (almost ready with Audio Technica MC cartridge and step-up transformer).
• A Rane AC24 active crossover (4 way) driving all power amplifiers.
This system, although not complete in terms of upgrading amplification, sounds good (relative term) to my ears. I can clearly distinguish each musical instrument and I must admit that the mids and highs have some of the best fidelity I have heard comparing to systems that cost much more $. In addition, the 6174s from McCauley are monsters when it comes to low frequencies generation.
My issue is the bass guitar does not sound as live and as high fidelity as I expected. I think that the 6224 McCauley’s should sound more realistic and defined.
My question is what is the best (relative term) hifi 8”, 10” or 12” driver for the frequencies of 80Hz or 100Hz to 800 Hz. The crossover points in my system are 100Hz, 800Hz and 3,200Hz. Thank you in advance for your feedback.
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My recommendation, before swapping out drivers, would be to do some measurements and figure out what the problem is or might be.
For instance, it looks like your crossover is analogue, so how have you approached time alignment?
How does the sealed box rolloff stack up with the electrical slope of the active crossover?
You get the idea.
It's possible that your lower-mid driver isn't integrating well with the other drivers, and some playing around with the crossover will fix that.
If not, you can use the measurement equipment to get the next driver dialled in.
FWIW, in the HiFi driver arena I'd look at the Seas metal cone units. If you fancy PA drivers, the Faital Pro 10FH520 is very good.
Chris
For instance, it looks like your crossover is analogue, so how have you approached time alignment?
How does the sealed box rolloff stack up with the electrical slope of the active crossover?
You get the idea.
It's possible that your lower-mid driver isn't integrating well with the other drivers, and some playing around with the crossover will fix that.
If not, you can use the measurement equipment to get the next driver dialled in.
FWIW, in the HiFi driver arena I'd look at the Seas metal cone units. If you fancy PA drivers, the Faital Pro 10FH520 is very good.
Chris
EXACTLY the combo I had for many years in my old 4-way speakers 🙂
and to indirectly answer you question: I used a 10'' Volt Midbass, can't remember the model exactly but maybe 25MB008?
Anyway, a very good driver indeed but today I would choose differently.
ATC+RAAL is a winner combo, no doubt. But there is a bit of overlap in each other's optimum range, though. Not a problem per se but they both excel between about 2.2khz and 6khz, and beyond. The ATC is also excellent down to roughly 800hz, but I wouldnt be afraid to use it from 1.1-1.2khz instead. Which makes it less useful...
So basically, you're looking for a low-mid-mid driver that excels up to 1khz, to give you some margin to play with all these drivers...
RAAL+ATC can deliver a lot of output, probably too much for most 8 inches drivers. So I'd go for a 10 or 12 and even a 15' if you can.
RV series from Volt (many models)
FaitalPro: 15PR400 or 12PR320 or 12FH520
Also other PA drivers available out there that can fit nicely.
If you're tight in space, yes Faital 10FH520 is a good option.
But since you only need a driver to go up to 800-1000hz, I would probably go with a 12 or 15 inches. Much more flexibility, and more energy in the 100-300hz, which is important.
you may need to adjust the relative balance of the drivers to bring out bass guitar. What is the cone material of the Macauley 6224 drivers? (It doesn't say on their web site). The systems I've built with best bass guitar sound tend to have coated paper cones. The large diameter voice coil, while great for power handling, may work against good upper response for those drivers, any FR graphs?
Acoustic Elegance TD15M - 15" Subwoofer
and probably every other 15" suggested in this thread. If 15" is too big and 12" is your limit
Acoustic Elegance TD12M - 12" Subwoofer
or any other 12" in this thread...
I think what you desire comes from high efficiency and sensitivity. I've read others looking for what you describe....and this is what I've seen pointed to as the culprit. Surface area is your friend but at that height (800hz) you probably want a single driver. From what I've gathered, the 15 is where its at.
This critical distance thing seems to be tied to everything as well....if this is true, heres some other potential solutions...shortening your listening distance should allow you to turn the volume down, consequently lowered distortion, and less room distortion. Otherwise it seems asking a single woofer to do handle the mid bass, at distance, is asking much, if it doesn't have complimentary surface area.
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I'd look at what the current setup does in your room.
If you have a room problem, every other driver at the same location is going to have similar troubles. It is quite common to have a floor bounce in the spectrum you're wondering about, that could mess up the experience for you. But you won't find out until you start to examine what you have.
If you have a room problem, every other driver at the same location is going to have similar troubles. It is quite common to have a floor bounce in the spectrum you're wondering about, that could mess up the experience for you. But you won't find out until you start to examine what you have.
It is torment to see wonderful speakers like these online and not be able to hear them!
Thank you for all the recommendations. I will take some measurements to troubleshoot and better analyze the issue before making changes. Thanks again.
Yes. Helinas said there is enough bass but it doesn't sound right. This is what I would try with the help of measurements.
To answer some of the questions above:
The active crossover Rane AC24 is a DSP based crossover incorporating an analog style user interface that has all the bases covered. The AC 24 is a dual-channel four-way unit, incorporating 4th-order 24 dB per octave Linkwitz-Riley filters, signal delay, and limiting functions.
The cone material for the McCauley 6224 is paper impregnated with some type of polymer. I attached a picture of the Rane AC24 that shows the limiters and delays for each output.
The active crossover Rane AC24 is a DSP based crossover incorporating an analog style user interface that has all the bases covered. The AC 24 is a dual-channel four-way unit, incorporating 4th-order 24 dB per octave Linkwitz-Riley filters, signal delay, and limiting functions.
The cone material for the McCauley 6224 is paper impregnated with some type of polymer. I attached a picture of the Rane AC24 that shows the limiters and delays for each output.
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As chris noted, you can have time alignment issue. Advance physically the subwoofer , I may guess about 20cm.
Depending on baffle area, centre to centre spacing, max SPL requirements and available cabinet volume, I would suggest either:
(1) The 12 inch LOUDSPEAKER 12"P80/Fe V2 8 OH
or
(2) The 15 inch LOUDSPEAKER 15"P80Fe/N 8 OH
They are both superb, ultra low Qts drivers which make them ideal for sealed box / low Vb applications.
Low Mms and powerful motors ensure the Mms to Bl ratio is excellent.
Also they have large 4 inch voice coils to handle high power and generous Xmax and mechanical travel.
Also the superb PD 158 is a great driver with similar epec and performance to the Beyma, the PD is more expensive with lower power (thermal) compression.
(1) The 12 inch LOUDSPEAKER 12"P80/Fe V2 8 OH
or
(2) The 15 inch LOUDSPEAKER 15"P80Fe/N 8 OH
They are both superb, ultra low Qts drivers which make them ideal for sealed box / low Vb applications.
Low Mms and powerful motors ensure the Mms to Bl ratio is excellent.
Also they have large 4 inch voice coils to handle high power and generous Xmax and mechanical travel.
Also the superb PD 158 is a great driver with similar epec and performance to the Beyma, the PD is more expensive with lower power (thermal) compression.
Sims for driver suggestions
Here are sims for the drivers.
Note, the ultra low Qts / Qes which makes them ideal for 0.5 Qtc critically damped loading.
Also outstanding Mms / Bl ratio ie low Mms and High Bl.
Also they all have high power 4 inch voice coils and generous Xmax and mechanical travel.
Here are sims for the drivers.
Note, the ultra low Qts / Qes which makes them ideal for 0.5 Qtc critically damped loading.
Also outstanding Mms / Bl ratio ie low Mms and High Bl.
Also they all have high power 4 inch voice coils and generous Xmax and mechanical travel.
I would look at the m-125, while it has the watts to be in this position it also has OPTs, inconsistencies in impedance in this range and tube choices to take into consideration. Your system has 3 different amplifier personalities, they may need some family therapy to all get along.
Correct Qtc 0.5 Beyma 15 inch sim
I posted the wrong sim (Qtc 0.707) in the above post... Here is the correct Qtc of 0.5.
It also has some Precision Devices 15 and 18 inch sim as well, plus some notes about using twin 15 inch as well... I was considering a few different options!
I posted the wrong sim (Qtc 0.707) in the above post... Here is the correct Qtc of 0.5.
It also has some Precision Devices 15 and 18 inch sim as well, plus some notes about using twin 15 inch as well... I was considering a few different options!
thank you HydrogenAlex for that sim.
Did you measured the T&S of these speakers ?
What about HD between two drivers withthe same Sd, the same BL but 2 diferent MMs please ? Is a 88g distorse more than a 125g in thes frequencies (100-600 hz) ? the lighter the bigger the breaks up so H2 to H5 numbers with overlapings ?
Did you measured the T&S of these speakers ?
What about HD between two drivers withthe same Sd, the same BL but 2 diferent MMs please ? Is a 88g distorse more than a 125g in thes frequencies (100-600 hz) ? the lighter the bigger the breaks up so H2 to H5 numbers with overlapings ?
I used the manufactures spec sheet for the TS spec.
I always favour a lighter cone and more powerful motor (high Bl) driver over a heavier cone / weaker motor for any given cone size.
Its the ratio of moving mass to motor strength that counts ie a powerful motor has a much better "grip" on the cone compared to a weak motor, and, a lighter moving mass is an easier "load" for the motor to control.
Here is a copy of a post I recently made on another thread, its appropriate here too:
A complex and as yet not fully understood (and rarely discussed) subject in loudspeaker driver design (and to a lesser extent, complete loudspeaker systems) is the time domain.
(1) From a snapping twig to a 100 piece orchestra in full swing, all airborne sound is 100% "APE" ie Air Pressure Event. A simple increase in air pressure (compression) or decrease in air pressure (rarefaction).
(2) The only two variables are the duration of the APE and intensity (level) of the APE.
(3) APE's are defined in and by TIME not frequency, APE's have a clear and measurable duration, they have a start and a stop time ie when the increase in air pressure starts, and how long it takes for the air pressure to decrease and stabilise back to ambient. The step response and CSD plots indicate how accurate a loudspeaker driver or complete loudspeaker design is in the time domain.
(4) The frequency of a sound is the direct result of the number of APE's per second.
Obviously there is much more to APE's and the time domain in sound than these 4 "starter for 10" points, but its a fascinating subject which is only just beginning to get some wider acceptance.
IMO, the bottom line to the OP question is this:
The driver/loading/crossover/Eq combination which results in the most accurate Time Domain reproduction of the original source (music/voice etc) APE will sound better.
Any delayed resonance caused by drivers bouncing around on their mechanical suspensions after the initial electrical impulse will distort the sound in a fundamental way. This time-domain distortion is the single worst type of distortion in the audio chain and 99.99% of it comes from the fundamental failing of all our loudspeaker drivers to react to, and then STOP reacting to(!) an electrical impulse.
The solution?
We need a mechanical loudspeaker driver which can react at the speed of electrical components... Now thats a tall order!!
I always favour a lighter cone and more powerful motor (high Bl) driver over a heavier cone / weaker motor for any given cone size.
Its the ratio of moving mass to motor strength that counts ie a powerful motor has a much better "grip" on the cone compared to a weak motor, and, a lighter moving mass is an easier "load" for the motor to control.
Here is a copy of a post I recently made on another thread, its appropriate here too:
A complex and as yet not fully understood (and rarely discussed) subject in loudspeaker driver design (and to a lesser extent, complete loudspeaker systems) is the time domain.
(1) From a snapping twig to a 100 piece orchestra in full swing, all airborne sound is 100% "APE" ie Air Pressure Event. A simple increase in air pressure (compression) or decrease in air pressure (rarefaction).
(2) The only two variables are the duration of the APE and intensity (level) of the APE.
(3) APE's are defined in and by TIME not frequency, APE's have a clear and measurable duration, they have a start and a stop time ie when the increase in air pressure starts, and how long it takes for the air pressure to decrease and stabilise back to ambient. The step response and CSD plots indicate how accurate a loudspeaker driver or complete loudspeaker design is in the time domain.
(4) The frequency of a sound is the direct result of the number of APE's per second.
Obviously there is much more to APE's and the time domain in sound than these 4 "starter for 10" points, but its a fascinating subject which is only just beginning to get some wider acceptance.
IMO, the bottom line to the OP question is this:
The driver/loading/crossover/Eq combination which results in the most accurate Time Domain reproduction of the original source (music/voice etc) APE will sound better.
Any delayed resonance caused by drivers bouncing around on their mechanical suspensions after the initial electrical impulse will distort the sound in a fundamental way. This time-domain distortion is the single worst type of distortion in the audio chain and 99.99% of it comes from the fundamental failing of all our loudspeaker drivers to react to, and then STOP reacting to(!) an electrical impulse.
The solution?
We need a mechanical loudspeaker driver which can react at the speed of electrical components... Now thats a tall order!!
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