For those of you who has implemented a dedicated bass amp (maybe a class D). What is your impression of such setup?
It probably wont give deeper bas but more "punch"?
It probably wont give deeper bas but more "punch"?
Class D (FM) amplifiers tend to be very accurate and can produce frequencies down to DC if allowed to and frequencies up to half the clock frequency.
For a bass amp in class D, a 40kHZ clock is adequate, 440kHZ (IRS2*** style) is an overkill but needs less iron in the filters.
For a bass amp in class D, a 40kHZ clock is adequate, 440kHZ (IRS2*** style) is an overkill but needs less iron in the filters.
Probably most class D amps are made for the full frequency range.
It was also the get some listening experiences with and without a dedicated bass amp for systems have a large bass unit (12"-18").
It was also the get some listening experiences with and without a dedicated bass amp for systems have a large bass unit (12"-18").
You mean Bass Guitar amplifiers or Woofer/Subwoofer drivers in active Hi Fi systems?
Very different areas.
Very different areas.
Just a bi-amp solution where the speaker crossover network is prepared for bi-amp. So you split the output from preamp. It could be a small low-watt amp to the tweeter/mid and a class-D for the bass speaker.
I know many configurations exists. But I know that some has built a M2X or ACA or another of the Pass amps then use a class-D for the bass unit. It was just how the difference is....or impression of the bass response with and without.....
I know many configurations exists. But I know that some has built a M2X or ACA or another of the Pass amps then use a class-D for the bass unit. It was just how the difference is....or impression of the bass response with and without.....
Hi Meper
I have been tinkering with a variety of bi-amp systems for the better part of 10 years.
I’ve tried several combinations.
I got my hands on a used First Watt B5 to make things easier. It is better than the Mini DSP I tried in my opinion.
I was working with some old Rotel HT amps for bass that were bridged to about 125 watts for a long time.
They were used with several amps I had built or own (ACA, F2J monoblocks, Quicksilver horn monos, Sony VFET) driving full range speakers.
I built a slot loaded bass panel at one point based on NP’s article.
It took me a while to get bass that I felt was right for the fullrange drivers I was experimenting with in horns and open baffles.
The bass panels didn’t work. I had to scale them down to fit reasonably in my living room.
No matter what I had powering them (6) 8” woofers per channel never produced bass like a 15-18” woofer.
I always had to use a HT sub to fill in what they lacked at the bottom end and even then the bass was boomy.
I found some Acoustic Elegance Dipole 15’s used. As soon as I put them in simple modest sized baffles and tried them in the system there was a huge change. I finally had bass and midbass.
However, there wasn’t quite the speed and impact I was looking for.
I then got my hands on some Hypex amps to try with the woofers.
Again, the change was impressive. There is no boomy bass, yet there is good impact and very good clarity. More power than I could ever need.
The last non biamped speaker I listened to was a pair of Tannoy System 15 DMT II that I bought this past year.
I played them with all my amps except the Hypex. They are lovely sounding, but they have none of the bass impact and clarity that my bi-amp system has when used like this. Perhaps I should have tried bi-amping them with the Hypex amps(Tannoy suggests a minimum of 50 watts in the manual)..but I love my FW DIY amps too much.
I am considering pulling the Tannoys and trying them active bi-amped open baffle with some Dipole 18 drivers I have.
Just my experience...hope it was entertaining.
I have been tinkering with a variety of bi-amp systems for the better part of 10 years.
I’ve tried several combinations.
I got my hands on a used First Watt B5 to make things easier. It is better than the Mini DSP I tried in my opinion.
I was working with some old Rotel HT amps for bass that were bridged to about 125 watts for a long time.
They were used with several amps I had built or own (ACA, F2J monoblocks, Quicksilver horn monos, Sony VFET) driving full range speakers.
I built a slot loaded bass panel at one point based on NP’s article.
It took me a while to get bass that I felt was right for the fullrange drivers I was experimenting with in horns and open baffles.
The bass panels didn’t work. I had to scale them down to fit reasonably in my living room.
No matter what I had powering them (6) 8” woofers per channel never produced bass like a 15-18” woofer.
I always had to use a HT sub to fill in what they lacked at the bottom end and even then the bass was boomy.
I found some Acoustic Elegance Dipole 15’s used. As soon as I put them in simple modest sized baffles and tried them in the system there was a huge change. I finally had bass and midbass.
However, there wasn’t quite the speed and impact I was looking for.
I then got my hands on some Hypex amps to try with the woofers.
Again, the change was impressive. There is no boomy bass, yet there is good impact and very good clarity. More power than I could ever need.
The last non biamped speaker I listened to was a pair of Tannoy System 15 DMT II that I bought this past year.
I played them with all my amps except the Hypex. They are lovely sounding, but they have none of the bass impact and clarity that my bi-amp system has when used like this. Perhaps I should have tried bi-amping them with the Hypex amps(Tannoy suggests a minimum of 50 watts in the manual)..but I love my FW DIY amps too much.
I am considering pulling the Tannoys and trying them active bi-amped open baffle with some Dipole 18 drivers I have.
Just my experience...hope it was entertaining.
Attachments
OB, yes, if you can make it exquisite big ...... only ("only") horn loading is better
if you can't make OB of proper size, you got ...... well, also exquisite solution
🙂
if you can't make OB of proper size, you got ...... well, also exquisite solution
🙂
I have using class D for 15" woofer (xover 800hZ) for summer due to class A heat issue.
In my experience, woofer amp is more important than tweeter woofer, and it determines overall sound character of the whole system, so choose it carefully. 🙂
In my experience, woofer amp is more important than tweeter woofer, and it determines overall sound character of the whole system, so choose it carefully. 🙂
Just a footnote
I still have not tried what I think would be a proper Class A bass amp.
It is my hope to build F5T amps to try in that role some day.
I still have not tried what I think would be a proper Class A bass amp.
It is my hope to build F5T amps to try in that role some day.
I had built and been dissatisfied with several sub systems I built. I had been also blindly trying to improve room acoustics with various treatments. It was not until I began measuring the room/speakers I was able to get a grasp of what was going on. Once I corrected a couple of peaks then things began to become more focused in the bass arena. I use a class d amp and use mini dsp to cross it. Since I moved into a larger house/ listening room I need larger speakers and considering bi-amping. I too am concerned about the Mini-dsp being the weak point but I do not like analog filters because I feel the alter more than frequency response of the crossover points. As far as speed and dampening I find my Alpha Nirvana amps up to the task for mid bass and am building a SissysitR3 for the highs.
Bill
Bill
In my case I have an OB system (OBL-15 as some may know).
It has a normal analog crossover that is is prepared for bi-amp. 15" woofer has its own separate crossover and is designed to "work perfect". So what I am after is how bass response change form using a single low power amp with relative low damping factor to an amp that has damping factor around 100 or so. Does that give the bass response more punch?
A large 15" / 18" woofer which often has 4" coil. That coil will generate an electrical pulse back to the amplifier after an "punch" from the amp. A powerful amp with high DF should be better to "eat" that impulse. So it was just how "audible" it is. I am not after.....right now......to make any equalization at the low end. The OBL-15 is designed so it goes all the way to the floor and has also panels at the back to prevent "shorting" of sound waves from the woofer. I wonder why so many OB-systems has rather small baffles and baffles where waves can travel between baffle and floor etc.
By the way.....I found a nice class-D amp offer. A model called STA-800D which has level control for both channels. So I decided to try it out. I can sell it again if is does not improve bass response. It would also mean something for the mid/tweeter low power amp as it get better "working conditions"? ...e.g. ACA, VFET and my 300B tube amp. I think it will look into a not so hard to drive impedance. But we will see.....
It has a normal analog crossover that is is prepared for bi-amp. 15" woofer has its own separate crossover and is designed to "work perfect". So what I am after is how bass response change form using a single low power amp with relative low damping factor to an amp that has damping factor around 100 or so. Does that give the bass response more punch?
A large 15" / 18" woofer which often has 4" coil. That coil will generate an electrical pulse back to the amplifier after an "punch" from the amp. A powerful amp with high DF should be better to "eat" that impulse. So it was just how "audible" it is. I am not after.....right now......to make any equalization at the low end. The OBL-15 is designed so it goes all the way to the floor and has also panels at the back to prevent "shorting" of sound waves from the woofer. I wonder why so many OB-systems has rather small baffles and baffles where waves can travel between baffle and floor etc.
By the way.....I found a nice class-D amp offer. A model called STA-800D which has level control for both channels. So I decided to try it out. I can sell it again if is does not improve bass response. It would also mean something for the mid/tweeter low power amp as it get better "working conditions"? ...e.g. ACA, VFET and my 300B tube amp. I think it will look into a not so hard to drive impedance. But we will see.....
OBL-15 gives "subjective" good bass response to just below 30 Hz when I try a test CD with low tones. At 20 Hz it is "dead". So if it should go all the way to 20 Hz a lot of equalization is needed (powerful amp).
In OBL-15 the 15" woofer takes over at about 180 Hz.
So the idea is just to connect the class-D amp to the terminal of the woofer analog crossover and utilize the work the designed has done to make the frequency response even. So start up with adjust class-D level to level of the small amp. It should be easy done via a sine test tone as input and then measure using a couple of DMMs.
So the idea is just to connect the class-D amp to the terminal of the woofer analog crossover and utilize the work the designed has done to make the frequency response even. So start up with adjust class-D level to level of the small amp. It should be easy done via a sine test tone as input and then measure using a couple of DMMs.
That is an attempt to achieve more of a dipole pattern, many of the simpler OB speakers don't.
Ok, but such systems will need equalization to get decent bass response.
OBL-15 is designed with a baffle size that gives decent bass response. So two different design philosophies I guess.
Or it will harm the efficiency. The design goal of OBL-15 is also the have a speaker with high efficiency.
OBL-15 is designed with a baffle size that gives decent bass response. So two different design philosophies I guess.
Or it will harm the efficiency. The design goal of OBL-15 is also the have a speaker with high efficiency.
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That's right, and at least 4 way with eq like Linkwitz's LX 531, I doubt such complexity is really worth it TBH.
My latest setup with dedicated bass amp (STA-1000D) and VFET amp for mid and tweeter is very nice. Bass control is very good and more "airy" than before. It can play "insane" loud without sounding compressed.
I have a feeling that VFET amp has more details compare to if it drives the whole speaker.
The SSII preamp is also back in service now as STA-1000D has 5k input impedance so a decent preamp is needed. SSII has 100R to RCA out. According to Pete Millett it should work but I could lower them to 10R or 22R. But seems to work fine "as-is".
STA-1000D has input level pots at the front. I played a test sine from a test CD and used a DMM to measure output from VFET amp and adjusted output from STA-1000D to same level.
I have a feeling that VFET amp has more details compare to if it drives the whole speaker.
The SSII preamp is also back in service now as STA-1000D has 5k input impedance so a decent preamp is needed. SSII has 100R to RCA out. According to Pete Millett it should work but I could lower them to 10R or 22R. But seems to work fine "as-is".
STA-1000D has input level pots at the front. I played a test sine from a test CD and used a DMM to measure output from VFET amp and adjusted output from STA-1000D to same level.
