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Build Your Own Professional-Grade Audio Amp on the Sort-Of Cheap

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Re: Build Your Own Professional-Grade Audio Amp on the Sort-Of Cheap

#251

Post by Scene_Cast2 »

comboy wrote: post #18

Any DAC chip and some usb interface for it that you could recommend to go with this? And slightly OT, but does anybody know any ABX test of balanced input/output signal? I find it hard to believe that there is a single person who can hear the difference.

https://www.audiosciencereview.com has measurements of various DACs. Tl;dr: the topping D50 ($250 MSRP) measures really well, and for a combo amp&dac unit the topping dx7s (currently on massdrop for $360) measures really well. Just a heads up, that site is biased towards objective measurements, the Toppings measure really well, so the site is biased towards them. A lot.

According to that site, Schiit stuff measures really bad.

List of all reviews: https://www.audiosciencereview.com/forum/index.php?threads/m...

Re: Build Your Own Professional-Grade Audio Amp on the Sort-Of Cheap

#252

Post by AnthonBerg »

mark-r wrote: post #248
AnthonBerg wrote: post #231

Earlier quoted context omitted.

Thanks but no thanks. When a transistor is off, it’s off. Then it takes a certain input voltage to get it going. Then there’s a varying curve to full output. In contrast, fully switching on or off “gets rid of the curve” and tranforms the problem into one of timing, and one of a modulation scheme for a series of on or off states. In that respect I contend that it is an useful thought to consider transistors’ behavior…

It's an interesting contradiction to build a more linear amplifier by intentionally using the transistors themselves in a non-linear fashion.

It is :) But it’s also only a contradiction on the surface of the words. The amplifier is quite linear even though the transistors aren’t used in what’s called their “linear region”, but I’d say they’re still used in a linear fashion.

Re: Build Your Own Professional-Grade Audio Amp on the Sort-Of Cheap

#253

Post by sjwright »

quakenul wrote: post #164
sjwright wrote: post #143

Earlier quoted context omitted.

The three critical paths for high end sound reproduction are: loudspeakers, speaker placement, room acoustics. Of course all parts of sound reproduction matter, but those three are the ones that affect real systems in practice. Most other factors are rarely an issue and/or inferior parts have a much lower magnitude of impact on sound quality. Sufficiently good source material (256kbps AAC or better) is widely availab…

Not in that order though, unfortunately: Unless you are using really shitty speakers, room acoustics trumps everything else pretty quickly. For anyone who has never listened to music in a well treated environment I found https://youtu.be/dB8H0HFMylo?t=355 to be pretty eye opening.

> Unless you are using really shitty speakers, room acoustics trumps everything else pretty quickly.

I agree completely, but emphasising that point tends to lead to flame-wars in most places on the internet. And it's such an imprecise subject to debate because everyone's room is different. Some rooms can be atrocious, while others can be unintentionally excellent. Some rooms can be easy to improve, some require knowledge and experience in order to improve. Some only require repositioning, some require treatment products that can cost a lot more than many enthusiasts realise.

My favourite video that demonstrates the effectiveness of acoustic treatment:

https://www.youtube.com/watch?v=cp56A6TcL1E

Re: Build Your Own Professional-Grade Audio Amp on the Sort-Of Cheap

#254

Post by brokenmachine »

Steve44 wrote: post #181
rubatuga wrote: post #33

If you just want the amp without building it, you can get a TPA3116 Class D amplifier. It is only $21 USD from aliexpress (with free shipping of course!). It accepts a supply voltage of up to 24V meaning that you can just dig around for your old laptop power supply (19V). It comes with a nice and sleek aluminum case, and has low enough noise floor that I can't detect it at all unless my ear is right up against the sp…

I know this isn't what the original article is about but for quite some time I used a Topping TP31 amp, it's the same technology you are talking about. It's not the best amp I've had, it's not loud enough for parties, or even very loud music, and it doesn't drive my planar headphones well. What it does do is easily fill my home/office room well above comfortable working & listening level, it drives my Sennheiser head…

TPA3116 can do about double the power of the TA2024 in the TP31 at about the same distortion.

The TPA3250 from the article, and the TPA3251/TPA3255 that have higher power from the same range are in a different class to those IMO, with much less distortion, and are just ridiculous value for money.

Re: Build Your Own Professional-Grade Audio Amp on the Sort-Of Cheap

#255

Post by dbrgn »

rubatuga wrote: post #33

If you just want the amp without building it, you can get a TPA3116 Class D amplifier. It is only $21 USD from aliexpress (with free shipping of course!). It accepts a supply voltage of up to 24V meaning that you can just dig around for your old laptop power supply (19V). It comes with a nice and sleek aluminum case, and has low enough noise floor that I can't detect it at all unless my ear is right up against the sp…

There also seem to be TPA3250 based amps all over Ali Express: https://de.aliexpress.com/item/NFJ-FXAUDIO-FX502S-PRO-HIFI-2...

Re: Build Your Own Professional-Grade Audio Amp on the Sort-Of Cheap

#256

Post by setquk »

KeytarHero wrote: post #246
setquk wrote: post #214

Earlier quoted context omitted.

Yes but the point is the signal path in those probably less than $100 end to end. Instruments excepted. A decent audio grade opamp is $2 for example.

I'm assuming you mean instruments and microphones excepted, because many high-end recording microphones cost $1000 and up. Yes, there are legends of a few albums being recorded with only a few SM57 (a $100 mic), but they're the exception - and most such albums aren't generally regarded as audiophile-quality. But regardless, even just the input transformer on most mixing consoles costs at least $100. And many extremel…

Yes I exclude instruments and transducers. Those are where the investment should be if anything.

You have no idea what you are talking about regarding signal chain. Discrete opamps are inferior on every possible measurement. This is total nonsense. Utter rubbish.

Do you know what noise figure is?

Do you know what CMRR is?

Do you know what PSRR is?

Re: Build Your Own Professional-Grade Audio Amp on the Sort-Of Cheap

#257

Post by pimeys »

scns wrote: post #209
pimeys wrote: post #203

Earlier quoted context omitted.

I don't know can I judge him. I listen to music all the time. Every imaginable genre that I happen to like. I'm not putting hundreds of thousands to my setup, but a good pair of headphones and a good headphone amp is a must for me in every office I work. Put some cash for Beyerdynamic DT-1770 Pro and been having a handmade headphone amp for the last 15 years, still using it. The sound cards differ, but now I'm ok wit…

Have you checked out the O2 headphone amp by nwavguy? It is mentioned in a toplevel comment in this thread.

I have a Corda HA2 mk3 and it still gives everything I need: enough punch to drive 250ohm headphones and a crossfeed to prevent fatigue when using them hours every day.

Maybe in 50 years when it breaks I'll get a new one :)

Re: Build Your Own Professional-Grade Audio Amp on the Sort-Of Cheap

#258

Post by mhh__ »

irrational wrote: post #26
Matsta wrote: post #10

The majority of all active speakers produced nowadays are Class-D, it's nothing really new (and the fact they are super cheap). No idea how this guy wrote this article and didn't come across DIY Audio (or he just didn't mention it in the article). There is a tonne of information here: https://www.diyaudio.com/forums/class-d/

I have some questions. My son has been taking guitar lessons using a classic guitar. Using the advice of his instructor we are getting him a begginer's electric guitar for christmas. We also need to get him an amp. Is the amp in this article the same kind of amp that you could plug an electric guitar into? I know nothing about music or instruments, but I do know about electronics so I was thinking it might be fun to…

Buy a Zoom G3x (or other good multi effects box with amps Sims) you can then chuck that straight into any semi decent guitar amp.

Re: Build Your Own Professional-Grade Audio Amp on the Sort-Of Cheap

#259

Post by Steve44 »

brokenmachine wrote: post #254
Steve44 wrote: post #181

Earlier quoted context omitted.

I know this isn't what the original article is about but for quite some time I used a Topping TP31 amp, it's the same technology you are talking about. It's not the best amp I've had, it's not loud enough for parties, or even very loud music, and it doesn't drive my planar headphones well. What it does do is easily fill my home/office room well above comfortable working & listening level, it drives my Sennheiser head…

TPA3116 can do about double the power of the TA2024 in the TP31 at about the same distortion. The TPA3250 from the article, and the TPA3251/TPA3255 that have higher power from the same range are in a different class to those IMO, with much less distortion, and are just ridiculous value for money.

That's interesting, thank you. I got the TP31 as it's got both headphone and speaker out plus it's own DAC. I've had it a few years so will have a look at the newer ones. Thanks.

Re: Build Your Own Professional-Grade Audio Amp on the Sort-Of Cheap

#260

Post by [deleted] »

fermienrico wrote: post #16

It is refreshing to see these types of articles. Of all disciplines of human interests and hobbies, Audiophiles are one of the most stubborn, misinformed, anecdotal and delusional bunch. Of course I am generalizing, but every time I engage in a discussion about audio quality, it is a losing battle. Not because of lack of data or supporting evidence, but because of the fundamental dissent for data driven arguments. Yo…

[deleted]
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