Again back to the self powered integrated speaker, how do we make sure we have that 3db of headroom at the max rated spl output? If we can control the chain through the speaker we know what we have. The question becomes how do you control the input voltage so that you won't exceed the designed max output with headroom, how to limit the input voltage to a max limit? If we could make sure we only had an input of say 2v maximum on the input or even 2.5v we could design the power amp so it would never clip, but how do we do that. how to attenuate the input so it never exceeds a limit?
ps. The only place for Tang is mixed with vanilla ice cream, makes a nice substitute for an Orange Julius.
ps. The only place for Tang is mixed with vanilla ice cream, makes a nice substitute for an Orange Julius.
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You either integrate the DAC, or control the gain upstream. For DIY its easy as you have complete control over the chain. Where the great unswashed are involved it gets harder.
2VRMS is pretty standard for most CD players and DACs, atlthough there is always balanced and pro equipment out there.
And (shock) you could put a limiter on your input. Just clip them if they get naughty.
But it is MUCH easy for the DIY'r to control.
2VRMS is pretty standard for most CD players and DACs, atlthough there is always balanced and pro equipment out there.
And (shock) you could put a limiter on your input. Just clip them if they get naughty.
But it is MUCH easy for the DIY'r to control.
Bill,
that is the question for a speaker that you are going to sell to the public who are not going to understand a gain structure. I can control everything inside the speaker including the dac and dsp with eq and FR correction, but I don't know what you are going to connect to it. I imagine that most phones, cdp, and many other consumer devices have similar outputs but who really knows for sure. A limiter on the input seems to be an intelligent way to go but how to do that without causing problems with the limiter, how do you do that without clipping the input signal or doing that sensibly so that it is a soft clip on the input with some kind of visual clip light that tells the consumer to back off the signal? What would a simple opamp based limiter look like, I am only familiar with pro-audio limiters and those certainly aren't small in any sense.
that is the question for a speaker that you are going to sell to the public who are not going to understand a gain structure. I can control everything inside the speaker including the dac and dsp with eq and FR correction, but I don't know what you are going to connect to it. I imagine that most phones, cdp, and many other consumer devices have similar outputs but who really knows for sure. A limiter on the input seems to be an intelligent way to go but how to do that without causing problems with the limiter, how do you do that without clipping the input signal or doing that sensibly so that it is a soft clip on the input with some kind of visual clip light that tells the consumer to back off the signal? What would a simple opamp based limiter look like, I am only familiar with pro-audio limiters and those certainly aren't small in any sense.
> But is headroom only 'effortless' if you KNOW
> you have a hugely OTT amplifier connected?
Everything else equal :
1 watt through a 10 watt amplifier will sound
constrained compared to 1 watt through a 100
watt amplifier .
> you have a hugely OTT amplifier connected?
Everything else equal :
1 watt through a 10 watt amplifier will sound
constrained compared to 1 watt through a 100
watt amplifier .
I'm going to have to let those versed in the art answer that as I have never looked at it, but know there is lots of silicon off the shelf than can as certain trick A/Ds get very upset if overdriven, or at least used to. Paging Scott!
I have a pair of self powered integrated speakers on my desk. They don't cost much, but they do give some audio output. Is this what you guys mean?
It kind of reminds me of how much quality that you need in an automobile:
I once drove a Renault Dauphine 95 thousand miles in a 5 year period (college) which had (optimistically) 32 HP. Yes, less than a VW bug (but the Renault was lighter). It could carry 4 passengers, and got similar mileage to some economical cars today. I took it just about everywhere, and could cruise at 65 mph on the freeway (the speed limit at the time) What did I learn from this?
One, it could be done successfully.
Two, it was economical (when it was working properly).
Three, there was rare that it could not go from A to B successfully.
What were the downsides?
One, it was relatively unsafe.
Two, it was slow to accelerate.
Three, it was unreliable, but I became my own mechanic to offset this.
Was this the best car overall? Not anymore.
I find that the rationalizations that many of you make over amp size, power, etc have a similar argument. The same with loudspeakers. '-)
It kind of reminds me of how much quality that you need in an automobile:
I once drove a Renault Dauphine 95 thousand miles in a 5 year period (college) which had (optimistically) 32 HP. Yes, less than a VW bug (but the Renault was lighter). It could carry 4 passengers, and got similar mileage to some economical cars today. I took it just about everywhere, and could cruise at 65 mph on the freeway (the speed limit at the time) What did I learn from this?
One, it could be done successfully.
Two, it was economical (when it was working properly).
Three, there was rare that it could not go from A to B successfully.
What were the downsides?
One, it was relatively unsafe.
Two, it was slow to accelerate.
Three, it was unreliable, but I became my own mechanic to offset this.
Was this the best car overall? Not anymore.
I find that the rationalizations that many of you make over amp size, power, etc have a similar argument. The same with loudspeakers. '-)
Back in 1974, John Meyer and I built an integrated amp speaker system consisting of 3 horn sections, 3 amps, a delay line (for the tweeter amp) and a derived 3 way electronic xover.
We used two commercial Marantz power amps and I built a special tweeter amp (the JC-3 power amp) for the project. It was very successful, but expensive. This is what I regard as a serious integrated amp-speaker project.
It WAS easier to get the best transient response with a derived xover compared to speaker coils, caps, etc. The delay line was quite a challenge, but worth it.
We used two commercial Marantz power amps and I built a special tweeter amp (the JC-3 power amp) for the project. It was very successful, but expensive. This is what I regard as a serious integrated amp-speaker project.
It WAS easier to get the best transient response with a derived xover compared to speaker coils, caps, etc. The delay line was quite a challenge, but worth it.
The ADAU1701 family have good digital limiters that can be tailored to not be intrusive when you bang on them. It's a 28 bit digital path and you should be able to handle any realistic analog input with plenty of headroom. The amps should never clip when it's all balanced correctly.
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Sent from my SGH-M919 using Tapatalk
No not at all. Kindhornman is doing something really quite interesting. The amplifiers I have ready for my speaker mods won't arc weld like your designs but otherwise have exemplary specifications and well in excess of anything needed for audio.
And don't forget you are forever linked with the WAMM active crossovers, even if you just lobbed a few extra bits in an off the shelf crown unit.
Something like this.... A motor is always best driven directly by the amp/controller....
http://atcloudspeakers.co.uk/hi-fi/loudspeakers/tower-series/scm300aslt/
Demian,
Thanks for that information, I wasn't aware that the 1701 chip could do that, it will make things much simpler then.
Bill,
You are correct and thank you I am trying to make something much better than a cheap desktop speaker you'd get for a few bucks with your desktop computer. I appreciate the complement.
Thanks for that information, I wasn't aware that the 1701 chip could do that, it will make things much simpler then.
Bill,
You are correct and thank you I am trying to make something much better than a cheap desktop speaker you'd get for a few bucks with your desktop computer. I appreciate the complement.
I did very little in the design of the WAMM, except that my technician supplied standard OPamp replacements with a hybrid jfet input, 5534 output on a minidip socket. However, the WAMM was one of the most fantastic speaker systems I have ever had the chance to hear. I used to visit Dave Wilson on occasion in the '80's and listen all evening on his WAMM system. It was a wonderful experience.
marce,
Nice to see you back. Sent you a couple of messages here and your personal email but didn't hear back. I have the list for you when your ready.
Steven
Nice to see you back. Sent you a couple of messages here and your personal email but didn't hear back. I have the list for you when your ready.
Steven
Of course, a 3 way, 3 amp system should be better than a single amp, 3 way system. Unfortunately my Wilson Sasha speakers are not designed with this in mind, but work fairly well anyway. I now biamp with a triode amp on top for my ultratweeter. Works great!
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