Im pretty sure the mds is all you want. It doesnt need much ampere as long as you dont play concert level. Of course it could sound inferior to mine, but it would be strange since its a more expensive model than mine. Also we cant be sure that its the same designer. Looking forward to impressions. PWhen will it arive?
Cheers!
Cheers!
Hi tomorrow morning i will go to get it
I have family problems but i hope to try it during the weekend for sure and report with pics
I am smart working and i like to hear my boss's voice in all its splendor
Seriously i am trying to improve my desktop pc audio system and the form factor of these little car amps is just perfect I can place the power supply beneath the desk
I have family problems but i hope to try it during the weekend for sure and report with pics
I am smart working and i like to hear my boss's voice in all its splendor
Seriously i am trying to improve my desktop pc audio system and the form factor of these little car amps is just perfect I can place the power supply beneath the desk
Who verifies that the MTBF is valid? They can print anything. I used to build a lot of computers and I can tell you that the power supplies regularly failed well before the MTBF rating. Things like internal protection are likely more important and it's very difficult to know the quality of those circuits.
If they use electrolytic caps, do they think that every single capacitor will last 50 years? Some may. Some will not.
You asked about fans. Do you think a fan will last 50 years? Some become intolerably noisy in just a couple of years.
I'm sorry but this again is a non-factor. The first power supply that you posted was likely perfectly good enough for what you want to do.
If they use electrolytic caps, do they think that every single capacitor will last 50 years? Some may. Some will not.
You asked about fans. Do you think a fan will last 50 years? Some become intolerably noisy in just a couple of years.
I'm sorry but this again is a non-factor. The first power supply that you posted was likely perfectly good enough for what you want to do.
I see and you are very right Maybe instead the name brand can say something? For instance in my pro dac i see one from Meanwell Usually products intended for a pro 24/7 use can be built with higher standards? For another tda7498e amp i have i am testing some smps usually installed in industrial control panels However i feel that a very good power amp can sound much better than a tda7498e cheap unit so i am much more interested in car audio
Next step would be to try some coaxial drivers for car to use as desk top little monitors
But this in the future
Thanks again for injecting sanity pills I tend to derail often being as much enthusiastic as ignorant
Next step would be to try some coaxial drivers for car to use as desk top little monitors
But this in the future
Thanks again for injecting sanity pills I tend to derail often being as much enthusiastic as ignorant
The TDA is rated at 0.05% THD. Do you think you can hear that? How would it sound, compared to an amp with 0.005% THD?
The speakers will inject far more distortion than any commercially available amp in good working order.
As far as coaxial speakers, some will sound awful, others better. Some may actually sound nice but they are the exception. The amplifier is the least flawed of the components in the system. For the most part, it will simply amplify and do little else to the signal. The speakers will have all sorts of problems, the frequency response will be the biggest problem in getting good quality sound.
The speakers will inject far more distortion than any commercially available amp in good working order.
As far as coaxial speakers, some will sound awful, others better. Some may actually sound nice but they are the exception. The amplifier is the least flawed of the components in the system. For the most part, it will simply amplify and do little else to the signal. The speakers will have all sorts of problems, the frequency response will be the biggest problem in getting good quality sound.
You should understand that speakers, of any type, are the worst part of the audio chain. Go to Parts Express and download various frequency response graphs to see how much the output level changes across the spectrum. Ideally, you would want a perfectly flat response across the entire range where the speaker will be used.
Parts Express: Speakers, Amplifiers, Audio Parts and Solutions
In this example, you can see the huge peak around 5kHz. This is essentially the same as having the 5k slider on an EQ boosted to a full +12dB. That's something that would have to be tamed with the crossover.
https://www.parts-express.com/pedocs/specs/294-3055--prv-audio-6mb200-4-v2-spec-sheet.pdf
This example is much better but more expensive:
https://www.parts-express.com/pedocs/specs/296-442-aurum-cantus-ac13050ck-specifications.pdf
The frequency response of the worst of full range amps is likely to vary more than 1dB across the full spectrum.
Bear in mind that the frequency response of the speakers is only one aspect. Some, even if they had the same frequency response, could be what some might refer to as 'articulate' while others would seem a bit less so (harder to pick out fine details). This is where reading reviews can help and PE has a lot of reviews.
Parts Express: Speakers, Amplifiers, Audio Parts and Solutions
In this example, you can see the huge peak around 5kHz. This is essentially the same as having the 5k slider on an EQ boosted to a full +12dB. That's something that would have to be tamed with the crossover.
https://www.parts-express.com/pedocs/specs/294-3055--prv-audio-6mb200-4-v2-spec-sheet.pdf
This example is much better but more expensive:
https://www.parts-express.com/pedocs/specs/296-442-aurum-cantus-ac13050ck-specifications.pdf
The frequency response of the worst of full range amps is likely to vary more than 1dB across the full spectrum.
Bear in mind that the frequency response of the speakers is only one aspect. Some, even if they had the same frequency response, could be what some might refer to as 'articulate' while others would seem a bit less so (harder to pick out fine details). This is where reading reviews can help and PE has a lot of reviews.
Thanks a lot again I was clearly putting too much importance on the amplification
I am much more fascinated by the electronics and their design and construction
Regarding the tda7498e the figures of low distortion you mention i guess they are at low power
Not an issue with efficient speakers what i intend to use
Thanks a lot again Time to put pieces together
I am much more fascinated by the electronics and their design and construction
Regarding the tda7498e the figures of low distortion you mention i guess they are at low power
Not an issue with efficient speakers what i intend to use
Thanks a lot again Time to put pieces together
Total harmonic distortion Po = 1 W - 0.05 - %
Actually what i would like to know is the max power on 4 ohm with 1% of distortion
But i can't see this in the datasheet
I wonder how many clean amperes this device is able to put out per channel i.e. Not bridged
I would like more a traditional ab amp possibly modifiable with better output transistors
In the weekend i will upload pics of two amps internals
Actually what i would like to know is the max power on 4 ohm with 1% of distortion
But i can't see this in the datasheet
I wonder how many clean amperes this device is able to put out per channel i.e. Not bridged
I would like more a traditional ab amp possibly modifiable with better output transistors
In the weekend i will upload pics of two amps internals
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The distortion varies across the spectrum. It's the lowest around 10-20W.
The IC doesn't have the best specs but with average quality speakers, it's likely that you couldn't tell the difference from a class B or AB amplifier. The higher distortion numbers are when the amplifier is pushed to its limits.
Don't blindly modify any amplifier. Sometimes changing the output transistors makes the bias unstable and the amp can fail catastrophically.
The output transistors (or any other transistors, resistors, capacitors...) have essentially nothing to do with the quality of the sound.
The IC doesn't have the best specs but with average quality speakers, it's likely that you couldn't tell the difference from a class B or AB amplifier. The higher distortion numbers are when the amplifier is pushed to its limits.
Don't blindly modify any amplifier. Sometimes changing the output transistors makes the bias unstable and the amp can fail catastrophically.
The output transistors (or any other transistors, resistors, capacitors...) have essentially nothing to do with the quality of the sound.
thanks for the very helpful advice. I cannot find the peak current out of this chip i mean looking at the LM3886 datasheet as an example
https://www.ti.com/lit/ds/symlink/lm3886.pdf
i see
so i guess it is much better to look elsewhere for some punch in the bass
Current is important to get a decent bass
thanks a lot. Am i in the phase of selecting an amp ... they repair and service many brands. For instance i read somewhere of a guy who sustained that a much smaller phoenix gold was sounding much better that a much bigger amp.
It seems that sound quality is not related to power and it is fine. SO what is it related to ? brand ? price ? setting some requirements which will be the best sounding stereo amp with let's say 100w/4ohm per channel ? it seems a little like a treasury hunt ...
When people start discussing the sound quality and that is mostly useless when it comes to amplifiers, especially when comparing the output/power stage of the amplifier. The preamp section can make a difference but I think I remember saying that you wanted a straight line preamp/no preamp section.
The power amplifier sections will sound precisely the same thanks to global feedback. The output of the amplifier is continuously monitored and when the SLIGHTEST error (distortion) occurs, there is an immediate correction. The output will always be an exact amplified version of the input to the amp as long as the amp is in good working order and is being driven into a load that it's designed to drive.
The first part of the system where you'll get any deviation in the signal is actually the speaker wire. It will induce more error than the amplifier itself. Even that is insignificant. The speakers are, by far, the weak point.
And don't get into a comparison between the way two amps sound unless it's a double-blind a/b test and the levels of the two amps are precisely matched.
The power amplifier sections will sound precisely the same thanks to global feedback. The output of the amplifier is continuously monitored and when the SLIGHTEST error (distortion) occurs, there is an immediate correction. The output will always be an exact amplified version of the input to the amp as long as the amp is in good working order and is being driven into a load that it's designed to drive.
The first part of the system where you'll get any deviation in the signal is actually the speaker wire. It will induce more error than the amplifier itself. Even that is insignificant. The speakers are, by far, the weak point.
And don't get into a comparison between the way two amps sound unless it's a double-blind a/b test and the levels of the two amps are precisely matched.
I don't think you can go by price or brand alone, I know I have seen some of the extreme stuff measure worse than budget brands.
But you still need to get a decent brand.
I use British made Genesis amp and Swedish DLS (though they are made elsewhere).
Both of these brands use Gordon's help from time to time. I believe Italian Hertz is also really good for its price.
I'm not sure how much power you actually need, my old Genesis amp is specified to 2x30W (though control measured to 2x56W at normal thd), and it will drive a 2 way front system to really high volume without any degradation of SQ.
Even the top brands use components that's not top of the line to save money, it's also a matter of how much time they can spend to fine tune each amp. Some engineers are better at designing things as well.
It's interesting to see how Gordon goes through and identify problems, he usually posts on Facebook with before and after measuring.
But you still need to get a decent brand.
I use British made Genesis amp and Swedish DLS (though they are made elsewhere).
Both of these brands use Gordon's help from time to time. I believe Italian Hertz is also really good for its price.
I'm not sure how much power you actually need, my old Genesis amp is specified to 2x30W (though control measured to 2x56W at normal thd), and it will drive a 2 way front system to really high volume without any degradation of SQ.
Even the top brands use components that's not top of the line to save money, it's also a matter of how much time they can spend to fine tune each amp. Some engineers are better at designing things as well.
It's interesting to see how Gordon goes through and identify problems, he usually posts on Facebook with before and after measuring.
Could be, but the amplifier I'm using now have been with me for 20 years off and on in a variety of cars with a variety of speakers. The speakers I'm using now have been used off and on in a variety of cars in many different installation configuration for +10 years.
I was working my way up through the current installation low on budget and trying different things when the amp went out, so to save money I had him fix it and at the same time I spent a little extra on upgrading it, and the difference was more than impressive.
Having talked to others who have done fine tuning by him or others on something they use tells a story. I have also used a variety of amplifiers without changing speakers or anything else, both for myself and for others, and there is difference.
I know amplifiers shouldn't be adding or subtracting anything to the sound, but my experience (for what it's worth) tells me they do.
Today it seems to be two camps as well, SPL or SQ, and from what I've read most people don't seem too impressed with the SQ of the brands that only focus on SPL. But I've never tried any of those, so it's just hearsay.
I was working my way up through the current installation low on budget and trying different things when the amp went out, so to save money I had him fix it and at the same time I spent a little extra on upgrading it, and the difference was more than impressive.
Having talked to others who have done fine tuning by him or others on something they use tells a story. I have also used a variety of amplifiers without changing speakers or anything else, both for myself and for others, and there is difference.
I know amplifiers shouldn't be adding or subtracting anything to the sound, but my experience (for what it's worth) tells me they do.
Today it seems to be two camps as well, SPL or SQ, and from what I've read most people don't seem too impressed with the SQ of the brands that only focus on SPL. But I've never tried any of those, so it's just hearsay.
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