Largely for testing purposes i need an amplifier with flat frequency response between 0 and 80khz.
But most amplifiers do not have a flat frequency response, most have a filter that will mess up measurements below 10hz (including most expensive ones).
Do i have to buy an amplifier and modify it or is it any good option where that isn't needed?
But most amplifiers do not have a flat frequency response, most have a filter that will mess up measurements below 10hz (including most expensive ones).
Do i have to buy an amplifier and modify it or is it any good option where that isn't needed?
Some Pass circuits go down to DC, like the 25 watt F5. It also goes up to 1MHz.
And there are some higher power versions of the F5.
https://www.firstwatt.com/pdf/prod_f5_man.pdf
https://diyaudiostore.com/collections/power-amplifier/products/f-5
https://diyaudiostore.com/collections/power-amplifier/products/f-5t
And there are some higher power versions of the F5.
https://www.firstwatt.com/pdf/prod_f5_man.pdf
https://diyaudiostore.com/collections/power-amplifier/products/f-5
https://diyaudiostore.com/collections/power-amplifier/products/f-5t
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I would like to get more power than 25W but for frequency response measurements you don't actually need that much.
How difficulties is it to use this one to build an AMP?
https://diyaudiostore.com/collections/power-amplifier/products/f-5t
Wouldn't class AB be better?
How difficulties is it to use this one to build an AMP?
https://diyaudiostore.com/collections/power-amplifier/products/f-5t
Wouldn't class AB be better?
You should build them like Nelson Pass designed them. The turbo can output 50W, or 100W as monoblocks.
By definition, frequency response is measured at 1 watt output into 8 ohms.
Construction is pretty easy with the supplied boards and chassis.
https://diyaudiostore.com/collectio...mate-amplifier-chassis?variant=39313327128649
Of course, you could built it on the cheap with an improvised chassis, and only one channel.
By definition, frequency response is measured at 1 watt output into 8 ohms.
Construction is pretty easy with the supplied boards and chassis.
https://diyaudiostore.com/collectio...mate-amplifier-chassis?variant=39313327128649
Of course, you could built it on the cheap with an improvised chassis, and only one channel.
100W per channel is definitely interesting. Main drawback i can see now is you then constantly using 200+W of power due to it being class A.
In terms of performance it's probably fine.
In terms of performance it's probably fine.
Ill see if there is any good class AB option for getting say 2x300W but it's not clear i will need more than 100W per channel in the first place.
Build your own with the Apex Microtechnology PA04 power op amp.
Circuitry is simple and DC is no problem. Just omit input coupling caps.
Not cheap, but it will work.
I'm working on a sub amp that uses four of these.
I've also built amps with its little brothers, the PA07 and PA12 power op amps.
Circuitry is simple and DC is no problem. Just omit input coupling caps.
Not cheap, but it will work.
I'm working on a sub amp that uses four of these.
I've also built amps with its little brothers, the PA07 and PA12 power op amps.
DIYA member Elvee designed one, for lab usage:
https://www.diyaudio.com/community/...-dirty-its-the-circlomos.154388/#post-1982379
https://www.diyaudio.com/community/...-dirty-its-the-circlomos.154388/#post-1982379
I see PA04 can supposedly do 200V and 20A peak which is massive overkill (4000W DC, 2000W AC)
PA07: instead offers 100V and 5A which is 250W AC.
Ill look into these 2. I was hoping to find some decent pre-build option but i guess that just doesn't exist.
Those are peak values and you never get the full PS voltage across the load.
My PA07 amp does 75 Wrms into 8 ohms continuous and the PA12 amp does 125 Wrms into 4 ohms continuous.
The PA04 amp isn't up and running yet but the data sheet conservatively estimates 400 Wrms.
What you do get largely depends on the power supply capacity / regulation.
My design philosophy has always been "overkill is better than performance limitations".
Best of success!
My PA07 amp does 75 Wrms into 8 ohms continuous and the PA12 amp does 125 Wrms into 4 ohms continuous.
The PA04 amp isn't up and running yet but the data sheet conservatively estimates 400 Wrms.
What you do get largely depends on the power supply capacity / regulation.
My design philosophy has always been "overkill is better than performance limitations".
Best of success!
I cannot spot any anti-DC filter here:
Looking at the manual it seems like the Cc capacitor will affect how high frequencies the amplifier will reproduce but i don't see anything regarding low frequencies.
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Yes, you are correct, that circuit will work down to DC.
I mentioned the coupling caps because they did have some app notes for audio amp circuits with input caps.
I mentioned the coupling caps because they did have some app notes for audio amp circuits with input caps.
https://www.top-electronics.com/en/power-op-amp-200v-20a-50v-µs
That's only for once channel right? (unbalanced mode) so you need to buy 4 to build a balanced 2-channel amplifier. 2 for unbalanced (610€).
buying 4 PA12 is also an option, should still give me enough power and costs 540$
https://www.top-electronics.com/en/power-op-amp-90v-10a
That's only for once channel right? (unbalanced mode) so you need to buy 4 to build a balanced 2-channel amplifier. 2 for unbalanced (610€).
buying 4 PA12 is also an option, should still give me enough power and costs 540$
https://www.top-electronics.com/en/power-op-amp-90v-10a
Yes, they are single channel, unbalanced output.
And, yes you can drive two of them out of phase to create a bridged or balanced output with theoretically 4X the power of one.
May I ask what your intended application is?
And, yes you can drive two of them out of phase to create a bridged or balanced output with theoretically 4X the power of one.
May I ask what your intended application is?
I am going to test some speaker designs using 2 to 8 subwoofers per channel.
My current dac (asus xonar STX) is unbalanced, ill probably upgrade at some point.
My current dac (asus xonar STX) is unbalanced, ill probably upgrade at some point.
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Have you considered high powered prosound amps, like the Crown XLi 2500, for example, which is 750Wrms per channel into 4 ohms and sells for only about $550 here in the USA.
Seems like that's easier, cheaper and quicker than a build.
Seems like that's easier, cheaper and quicker than a build.
And where does the DC requirement come from when testing subs?
Not trying to be negative, just want to understand. Thanks.
Ill look into them but accurate frequency response is more important than high wattage for the project.
What anti-DC filters does is to filter out low frequency sounds.
The benchmark AHB2 for example seems to have a first order high-pass filter at 0.1hz which while less problematic than most competitors is not something you actually want if your subwoofer can handle these very low frequencies just fine.
I have also read that some amplifiers will outright shutdown if there is is too much high intensity of low frequency signals in order to 'protect' your speakers (which usually cannot be adjusted or disabled).
If anything i would benefit from protection against high intensity high frequency signals such as 300W @ 6khz, most tweeters cannot handle that.
But it's fairly easy to make a speaker that can handle 300W at 0.001hz.
But it's fairly easy to make a speaker that can handle 300W at 0.001hz.
That would be the DC fault protection to prevent the voice coil from going up in smoke.
One could change the time constant so that it doesn't trip at very low frequencies but it would be quite slow to act in case of real DC on the output terminals.