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Topic: Bluetooth, transcoding and audio quality (Read 10462 times) previous topic - next topic
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Bluetooth, transcoding and audio quality

Hello everyone, this is my first post and I would like, first of all, to thank all the information I have been gathering about audio codecs in general in this forum.

I have a good collection of archived CDs in FLAC format that I often listen to through an Android cell phone with microSD card, both via USB cable to external DAC or via bluetooth. Over the last few years, in order to load the microSD with my entire collection, I have used MP3, OGG, Opus, Musepack and more recently LossyWAV (thanks Nick), as the capacity of the cards has increased. Right now I have a 2TB microSD (Sandisk just released it), and I can finally load all my music in FLAC.

For wired listening it's clear that lossless is the best option, but is it also the best option for bluetooth listening? We immediately think that if we start from FLAC we avoid transcoding, but I am not sure that this is the best, let me expose the two scenarios:

1. FLAC format, the audio is transformed to PCM, encoded by SBC, sent, and in the speaker or bluetooth headset is transformed back to PCM. As SBC works at about 328kbps, we leave it to a codec with a basic psychoacoustic model and with hardly any development to decide what information to preserve.

2.  Musepack Q9 format (or Opus 320kbps, or MP3 320, or a good codec around 328kbps bandwidth). OK, it's converted to PCM and transcoded to SBC, but what is this PCM composed of? Above 320kbps of well-chosen information, isn't it filled with redundant or non-significant information (zeros) when transformed to PCM? And isn't that redundant or non-significant information easily discarded by the SBC codec?

In short, don't the two scenarios boil down to listening to a good codec at 320kbps vs. SBC at ~320kbps?
Surely this theory is wrong. In that case, if transcoding were to affect the lossy codec, is there some reason intrinsic to the Musepack, Opus or MP3 format why one would be less affected versus the others?

I must say I have not done extensive ABX testing but both options are satisfactory to me and I can't say for sure whether or not there is a difference. There is also a Bluetooth A2DP SBC/aptX online encoder from Valdikss to compare the effect of these two codecs, but I don't draw any conclusions either (I don't know if it is allowed to post the link).
Maybe my ears don't have much hearing ability anymore. But I would like to know the technical opinion of who can shed some light on what happens to the audio when sent over bluetooth. aptX has a higher bandwidth and reputation of being a better codec than SBC, it would be a third scenario to evaluate.

Greetings to everyone!

Re: Bluetooth, transcoding and audio quality

Reply #1 –
You seem to have gone into it pretty thoroughly, but you might still find this interesting: https://www.audiophile-heaven.com/2023/03/bluetooth-sound-quality-guide-what-are-the-codecs-and-how-do-they-work.html

I think what you're talking about is possible adverse interactions when re-encoding from the storage format to the Bluetooth transport format.  Using a lossless storage format will always be the gold standard, because the decoded PCM is exactly what went in, therefore the storage format is transparent and can have no interaction with the Bluetooth transport.

Trying to analyse the interactions between lossy formats is a can of worms, best guided by what is, to your ears, good enough.
It's your privilege to disagree, but that doesn't make you right and me wrong.

Re: Bluetooth, transcoding and audio quality

Reply #2 –
Quote from: Chordeater on
we leave it to a codec with a basic psychoacoustic model and with hardly any development to decide what information to preserve.
To the best of my knowledge, SBC is a low complexity side band codec. No psychoacoustic model in sight. It has been released around 2000 so had to be very frugal on system resources.

IMHO a lossy format results in generation loss. Using a lossy source and a lossy Bluetooth codec is a cumulation of generation loss.
If it is audible in practice, is a different story.
TheWellTemperedComputer.com

Re: Bluetooth, transcoding and audio quality

Reply #3 –
When listening, there won't be any significant difference, or possibly no difference at all between the two. SBC isn't the best Bluetooth codec out there, but at 330 kbps the result is more than satisfactory. It shouldn't be too difficult to find some artifacts on particularly complex musical passages, but the overall quality is good.

Therefore, having files already encoded with a high quality lossy encoder or in FLAC won't lead to anything noteworthy. If you have enough space on the SD card to put everything in FLAC, and if you don't need to store anything else, then keep the FLAC encoding on the SD card. It will make a good backup, which can always be useful. Enjoy your 2TB SD card!

If you have the option to choose LDAC or LHDC protocol in the future, it will also seem more relevant to go with a lossless library on your phone (even if I doubt any difference other than placebo can be perceived between lossless sources and HQ lossy ones).

As usual: if you have more than enough free space go with lossless; otherwise transparent lossy is perfectly fine with Bluetooth. A second generation loss have little if any audible difference.
Wavpack Hybrid -c4hx6

Re: Bluetooth, transcoding and audio quality

Reply #4 –
Thank you for your answers.
 
Quote from: fooball on
Using a lossless storage format will always be the gold standard, because the decoded PCM is exactly what went in, therefore the storage format is transparent and can have no interaction with the Bluetooth transport.
But that PCM signal contains 1411kbps of information, and bluetooth transmission via SBC only allows to send (usually) 328kbps, so a good part of the information is lost, and the part that is lost is decided by the basic SBC codec.

Quote from: Roseval on
Quote from: Chordeater on
we leave it to a codec with a basic psychoacoustic model and with hardly any development to decide what information to preserve.
To the best of my knowledge, SBC is a low complexity side band codec. No psychoacoustic model in sight. It has been released around 2000 so had to be very frugal on system resources.

IMHO a lossy format results in generation loss. Using a lossy source and a lossy Bluetooth codec is a cumulation of generation loss.
If it is audible in practice, is a different story.
Although I am not an expert by any means, I refer to a basic psychoacoustic model because sub-band coding (SBC) breaks a signal into a number of different frequency bands and eliminates those that are masked by others (auditory masking). Ok, maybe you can't even call it a psychoacoustic model.
But the key is what exactly is added when, starting from a lossy codec, the signal is transformed to PCM, and what is removed when SBC (or aptX) re-encodes it. And how does that loss of relevant information (if any) compare to the loss that occurs when encoding an uncompressed file through SBC.
For example we know that Opus 192kbps is transparent, if SBC processing preserved that information, it would still be transparent at the end of the audio chain ... 192kbps is the minimum bandwidth that is transmitted via SBC. Ideally, that information would fit in the minimum bandwidth of the SBC transmission (which is just 192kbps), but I fear that such frequency band elimination processing would mean eliminating relevant information as well.

Any other input or tests related to the differences between these two scenarios would be welcome.

Re: Bluetooth, transcoding and audio quality

Reply #5 –
Quote from: guruboolez on
When listening, there won't be any significant difference, or possibly no difference at all between the two. SBC isn't the best Bluetooth codec out there, but at 330 kbps the result is more than satisfactory. It shouldn't be too difficult to find some artifacts on particularly complex musical passages, but the overall quality is good.

Therefore, having files already encoded with a high quality lossy encoder or in FLAC won't lead to anything noteworthy. If you have enough space on the SD card to put everything in FLAC, and if you don't need to store anything else, then keep the FLAC encoding on the SD card. It will make a good backup, which can always be useful. Enjoy your 2TB SD card!

If you have the option to choose LDAC or LHDC protocol in the future, it will also seem more relevant to go with a lossless library on your phone (even if I doubt any difference other than placebo can be perceived between lossless sources and HQ lossy ones).

As usual: if you have more than enough free space go with lossless; otherwise transparent lossy is perfectly fine with Bluetooth. A second generation loss have little if any audible difference.

Yes, that's my experience, differences are minimal if any. I will do some tests and try to draw conclusions, but I will indeed keep the files in FLAC because I also connect the mobile by cable to my HiFi equipment and I understand that it is the winning horse.
Since microSD cards seem to be dying out in high-end phones, I plan to make a copy in Musepack Q9 so that, in the future, I can carry music on the phone's internal memory.

Re: Bluetooth, transcoding and audio quality

Reply #6 –
Quote from: Chordeater on
But that PCM signal contains 1411kbps of information, and bluetooth transmission via SBC only allows to send (usually) 328kbps, so a good part of the information is lost, and the part that is lost is decided by the basic SBC codec.
I fail to understand the relevance of that point.  The lossless 1411kbps is as clean a signal as you can ever get, so does not contribute to any loss in the subsequent Bluetooth codec.
It's your privilege to disagree, but that doesn't make you right and me wrong.

Re: Bluetooth, transcoding and audio quality

Reply #7 –
Quote from: fooball on
Quote from: Chordeater on
But that PCM signal contains 1411kbps of information, and bluetooth transmission via SBC only allows to send (usually) 328kbps, so a good part of the information is lost, and the part that is lost is decided by the basic SBC codec.
I fail to understand the relevance of that point.  The lossless 1411kbps is as clean a signal as you can ever get, so does not contribute to any loss in the subsequent Bluetooth codec.
Sorry, it was a translation problem, I'm the one who didn't understand what you meant by “no interaction”.

Re: Bluetooth, transcoding and audio quality

Reply #8 –
That webpage recommended on the second post, i think, fails to delve into the most important aspect of the issue at hand. The various bluetooth codecs offered are all codecs. Which means, they all have their own compression algoritms for taking the data from the original source files and recompressing (re-encoding) them, god knows in what quality and to what extent, and then delivering it to the device with the DAC and Amplifier to then decode and play. That is like additional noise.

In my opinion, the best potential codec for bluetooth audio would be the codec that "would not" require a reencode just to be delivered to the target, which means, if possible, just send the actual audio file that is stored in the source device, without any modification, turn it into pcm in the target device and send it to the dac or amp to play. AAC is probably the only one which can manage to do that as of now.

All those codecs mentioned on that website are proprietary codecs and none of us keep our music collection in those codecs. (AAC is the exception). So when i throw a vorbis file, a flac file, an mp3 file or an opus file to those codecs, regardless of its actual quality, whatever these codecs do to my precious bits is uncertain. Maybe their compression algoritm takes the FLAC and turns it into absolute garbage, how can we even confirm that the quality is constant? Has anybody even abx'ed those codecs, without the bluetooth aspect of it.

So apple has aac which probably resolves that but what about "non-apple" users. Opus, if it manages to slip into bluetooth territory, could allow us to actually send unmodified opus files without the need of any reencode to any other codec, directly to the target device for playback. Nowo that could be the "lossless bluetooth" standard that we hope for (not actual lossless but you understood what i mean there). I think most of us would buy an opus codec suporting playback device solely for that reason.

PS: I do not use AAC on my android smartphone (aac supported) and bluetooth earbuds (also aac supported) because of the fact that when i compare SBC to AAC, AAC always fails to deliver the transients in my music files. Cymbals sound like garbage when i use aac. I don't know the reason. Maybe because i do not keep my music as aac (maybe all bluetooth listeners should). Maybe my android phone's aac encoder sucks. Or maybe thea aac decoder on my bluetooth buds is not good. There are too many variables.

Re: Bluetooth, transcoding and audio quality

Reply #10 –
Quote from: Replica9000 on
You would think if you're playing AAC files, and both your device and headset supports the AAC codec, it would just pass through the data, but that's not the case.  At least not with Android.  Seems the experience will vary with different phones.

https://www.soundguys.com/the-ultimate-guide-to-bluetooth-headphones-aac-20296/

I wouldn't expect anything less than an apple supported codec. I remember back when their ipods were in everybody's pocket. They did not include a software compressor or limiter to that device and any music you play with it was clipping like crazy. Especially if you play with the EQ settings. It was the worst DAP in the market. Thank goodness then came "rockbox" and solved the issue for them, "free of charge". For my music, I wouldn't rely on anything with apple's name on it.

Re: Bluetooth, transcoding and audio quality

Reply #11 –
Interesting things have been said in this thread. It seems incredible, but we are almost in 2025, high definition audio has been well established for years, there are plenty of bluetooth devices, and we still don't have CD quality in bluetooth transmission ...

After all I have read in this forum, it seems that starting from FLAC and avoiding transcoding is after all the best option. And if you start from a lossy file, Wavpack over 400kbps or maybe Musepack Q9-10 are the options to consider ( https://hydrogenaud.io/index.php/topic,24592.0.html ), although as noted there are many variables (starting bitrates/bluetooth codecs, hardware implementations ... ) and it is very difficult to determine.

Too bad about the inconsistency of AAC on Android, on devices that support it I avoid it too, I tend to notice bloated bass and a loss of definition. I read about Opus integration from Android 13 on Pixel devices, hopefully it will be extended to other brands and devices.

Cheers.

Re: Bluetooth, transcoding and audio quality

Reply #12 –
Quote from: lovecraft on
Quote from: Replica9000 on
You would think if you're playing AAC files, and both your device and headset supports the AAC codec, it would just pass through the data, but that's not the case.  At least not with Android.  Seems the experience will vary with different phones.

https://www.soundguys.com/the-ultimate-guide-to-bluetooth-headphones-aac-20296/

I wouldn't expect anything less than an apple supported codec. I remember back when their ipods were in everybody's pocket. They did not include a software compressor or limiter to that device and any music you play with it was clipping like crazy. Especially if you play with the EQ settings. It was the worst DAP in the market. Thank goodness then came "rockbox" and solved the issue for them, "free of charge". For my music, I wouldn't rely on anything with apple's name on it.

Yes, a few years ago I had a couple of 240GB (modded) iPods  with RockBox. Good times.

Re: Bluetooth, transcoding and audio quality

Reply #13 –
I did some testing with my humble setup (ARCH Linux, pipewire). I listen to my music using rather basic bluetooth earbuds (two different pairs). They aren't "bad" products per se and have decent amps inside them, they sound good (to me) however, they are not audiophile class. They only support SBC and AAC. I can also select SBC-XQ and i can see that "joint stereo" turns into "dual channel" which i assume is much better and sends more kilobytes to the buds. One of the pairs struggle with SBC-XQ but the other one can take it. Now when it comes to AAC encoding/decoding, i assume it is a rather tricky business, and most cheap earbuds can't really do it well and it really shows in my case. The "on the fly" encoding of Linux bluetooth stack is probably also not great. If i select AAC as the codec of transport via my pc, the audio definitely gets muffled (especially the top end). The same with my android smartphone. AAC is the default codec, but i disable it and use only SBC instead because it sounds better. This coincides with the above linked soundguys article.

So, i wanted to know if i will actually hear any difference between the original FLAC file and the 96kbps opus file i encoded from that particular flac. I picked the better pair of my earbuds which support sbc-xq. I used audacity for the job. This is the closest i can get to an abx text with my setup, as you know, foobar2000 is not available for Linux (which is an absolute disgrace for the whole audiophile community). I know it can be installed via wine but i don't want to install windows stuff on my Linux machine.

Anyway, i loaded both the flac and opus files to audacity. They are perfectly in sync (time wise). That made it so much easier to cut the same intervals from both files and loop them back to back. I specifically selected the parts with the most transients (crash, ride, splash, hihat etc.). I also found a glass breaking sound which is also quite random and probably very hard to encode.

Now it is very anticlimactic, i know but, in the end, i heard absolutely no difference between the flac and 96kbps opus files. Now that might mean more than one thing:

1. It is quite possible that my hearing is toast, which is normal at my age (44).

2. It is also possible that opus is such a great codec that even at 96kbps, it does an absolutely amazing job at preserving authenticity of the original audio data.

3. It is possible that the equipment that i am using is simply bad (or a combination of other factors). Maybe if i had LDAC or AptX supporting earbuds, i would be able to pick up the difference. Concurrently, that should mean that SBC is such a bad codec, no matter what you feed it with (quality wise), it beats it to a pulp and sends absolute garbage to the speakers and because you are not an audiophile with a better setup, you have no idea that you are actually listening to subpar audio.

I don't own a headphone amp and better wired headphones or a better setup to compare. Maybe i should invest in those things. I am a casual listener. I am content with what i hear from these buds. But i expected that i could hear some difference between the flac and such low bitrate opus encodes. Well i couldn't. What you make of this is up to you.

Re: Bluetooth, transcoding and audio quality

Reply #14 –
Quote from: lovecraft on
i can see that "joint stereo" turns into "dual channel" which i assume is much better and sends more kilobytes to the buds.
Joint Stereo is a means to reduce the data bandwidth required without loss of quality.  It exploits the commonality between L and R by encoding them as L+R and L-R.  There is no benefit in decoding to separate L and R unless the transmission medium is unable to accommodate L+R/L-R encoding.

MP3 Joint Stereo may switch between L&R or sum&difference according to which consumes least bytes.
It's your privilege to disagree, but that doesn't make you right and me wrong.

Re: Bluetooth, transcoding and audio quality

Reply #15 –
Quote from: fooball on
Quote from: lovecraft on
i can see that "joint stereo" turns into "dual channel" which i assume is much better and sends more kilobytes to the buds.
Joint Stereo is a means to reduce the data bandwidth required without loss of quality.  It exploits the commonality between L and R by encoding them as L+R and L-R.  There is no benefit in decoding to separate L and R unless the transmission medium is unable to accommodate L+R/L-R encoding.

MP3 Joint Stereo may switch between L&R or sum&difference according to which consumes least bytes.

I was talking about the SBC bluetooth codec there. Standart SBC is joint stereo. When you swith to SBC-XQ, it becomes dual channel, which means that the bluetooth stack sends two different streams for the stereo channels and that directly increases the bitrate. This requires a higher bitpool and not all earbuds can take that much data in real time and process it. They have to have a decent processor in them.

PS: I uploaded two of the loops i generated. Maybe it might be of interest. I exported one of them as 44.1khz and the other one as 48khz, to accomodate both the original flac and opus resampling.

Re: Bluetooth, transcoding and audio quality

Reply #16 –
Quote from: Chordeater on
Interesting things have been said in this thread. It seems incredible, but we are almost in 2025, high definition audio has been well established for years, there are plenty of bluetooth devices, and we still don't have CD quality in bluetooth transmission ...

I don't get this either. Surely implementing low-latency 16/44 loseless even over a 1mbps link should be trivial by now. Is there a conspiracy against such a thing by Big Streaming?

Its still less ridiculous than SPDIF not supporting native source volume control outside of computers though, like who even cares about digital bit depth reduction outside of audiophiles. (Very unlikely to pass any level-matched ABX in sane usage scenarios anyway)

 

Re: Bluetooth, transcoding and audio quality

Reply #17 –
Quote from: lovecraft date=1740257683
I don't own a headphone amp and better wired headphones or a better setup to compare.
All that headphone amps do*, and in the best case scenario, is to pump up the volume.

Anything extra - no matter what nice name audiophools give it - is distortion, harmonics and what-not, - AKA 'signature' in good audiophile rambling style.

Notoriously, some would take a reverse loan for simply getting that crap (I'm looking at you, Tom Selleck! :)) )


* edit: like all other amps
• Listen to the music, not the media it's on
• The older, the 'lossier'

Re: Bluetooth, transcoding and audio quality

Reply #18 –
> The "on the fly" encoding of Linux bluetooth stack is probably also not great

No, on an up-to-date system Bluetooth/AAC is actually sounding great to me, and also seems to pick the highest negotiable bitrate. It's really a wonder how it works, and a life saver in case you have some earbuds from a stupid company like Samsung, which drastically limit SBC bitpool to make SBC near useless (e.g. trumpet sound turns into an absolute mess).
Also there is nothing hard per se about "on the fly" encoding here, especially on desktop - AAC encoding in general is much faster than realtime.

But there could be another element, which ValdikSS described in their article - earbuds can also apply different DSP depending on which codec is used, so this could be also a reason for muffled sound.

> absolutely no difference between the flac and 96kbps opus files

This is normal, Opus is that good for most types of audio. There are certain killer samples but it is unlikely to run into them unintentionally and understand what to focus on to hear the difference unless you specifically want to do that.
And re. p.3, no, SBC is just fine if used at maximum bitrate, the problem is that it's hard to know if it will refuse to work at maximum bitrate.
a fan of AutoEq + Meier Crossfeed

Re: Bluetooth, transcoding and audio quality

Reply #19 –
I keep thinking about how to bring bluetooth transmission closer to transparency. Earlier in this thread it has been discussed that, in bluetooth transmission, the chain is: re-encode to PCM, apply the codec (SBC, aptX, ...) send it to the device, and back to PCM. If you don't start from FLAC, a transcoding takes place. At the beginning of the thread I was asking whether two good encodings (a) would be better than one ‘bad’ encoding (b).  That is:

(a) I compress with a good codec (opus/musepack/whatever) at 320kbps and hope that when it is converted to PCM it is filled with redundant information, so that when SBC (a ‘dumb’ and primitive codec) is applied it does a good job and the initial information contained in the 320 is preserved.

(b) I start from FLAC (so the PCM is full of diverse and relevant information) and let SBC decide what to preserve.

It was more or less concluded that SBC by itself does well enough, and that a transcoding will affect the final result more, because the bluetooth transmission is quite obscure and who knows what the PCM is filled with.

I've read that Wavpack doesn't use a psychoacoustic model in the style of LAME or Opus, and that it is very suitable for transcoding.
Given that SBC typically has a bandwidth of 328kbps (354kbps for aptX), do you think Wavpack at 320kbps is the best choice for use on bluetooth devices?

Re: Bluetooth, transcoding and audio quality

Reply #20 –
Quote from: includemeout on
Quote from: lovecraft date=1740257683
I don't own a headphone amp and better wired headphones or a better setup to compare.
All that headphone amps do*, and in the best case scenario, is to pump up the volume.

Anything extra - no matter what nice name audiophools give it - is distortion, harmonics and what-not, - AKA 'signature' in good audiophile rambling style.

Notoriously, some would take a reverse loan for simply getting that crap (I'm looking at you, Tom Selleck! :)) )


* edit: like all other amps

It is not that simple with the amplification thing. If you buy the latest state of the art studio monitor headphones or IEMs which cost an arm and a leg, you'd think that you'd just plug them to your player (or phone) and beautiful music would pour out of them. Well, you'd be mistaken. These products come with no amps and the manufacturer expects you to pair them with a quality amp. You see, an amp is not just to increase the signal. You can increse the signal level all the way and all you'd be hearing would still be a flimsy noise with weak bass and all sibilant and irritating high frequencies without any substance at all. An amp is an essential part of any audio setup and its quality is directly responsible for the quality of the output. Amplifiers shape the sound. They shape the sound in a way to match the speaker system that they are connected to. That is why you can not power a headphone with a rack amp or can't power your tower speakers inside your living room with a headphone amp.

Bluetooth earbuds come with their own amplifiers (one in each piece). Cable buds do not come with an amp, so a headphone amplifier is necessary. For smartphones ditching the headphone jack in recent years was actually also ditching the cheap headphone amplifier that they had to toss inside their devices. I can understand that people got angry with this decision but some of those devices had the worst amplifiers inside them, and it is actually better if you just use them as players and pair them with a good headphone amp that you choose (which is what bluetooth earbuds do). I remember having a second generation Ipod Nano, and that thing also had one of the worst amps ever :) And the "clipping", oh my god. There was no limiter in those things. And it was the time of "loudness wars". It was really a horrendous experience compared to today so i can totally understand the "audiophile" movement born out of that. At least now we have the ability to shape the sound via software and there are more and better hardware options out there.

Re: Bluetooth, transcoding and audio quality

Reply #21 –
Quote
Amplifiers shape the sound. They shape the sound in a way to match the speaker system that they are connected to.
WRONG! The amplifier's job is simply to amplify.   An ideal amplifier is often described as "a straight wire with gain".

Most amplifiers do a very good job of that unless you overdrive it into clipping/distortion.     Sometimes there is audible noise (hum, hiss, or whine in the background). 

Of course if it has tone controls or EQ, that an alter the sound.

Quote
That is why you can not power a headphone with a rack amp or can't power your tower speakers inside your living room with a headphone amp.
A low-power amplifier is often fine.   Sometimes the same chips designed as low-power speaker amps are used to make headphone amps.   High-power amplifiers have too much output voltage and gain.   You might accidently blow-out your headphones/IEMs or your ears!   And the higher gain amplifies any background noise which is more noticeable with something next to, or inside, your ear.  

Re: Bluetooth, transcoding and audio quality

Reply #22 –
Quote from: DVDdoug on
Quote
Amplifiers shape the sound. They shape the sound in a way to match the speaker system that they are connected to.
WRONG! The amplifier's job is simply to amplify.   An ideal amplifier is often described as "a straight wire with gain".

Most amplifiers do a very good job of that unless you overdrive it into clipping/distortion.     Sometimes there is audible noise (hum, hiss, or whine in the background). 

Of course if it has tone controls or EQ, that an alter the sound.

Quote
That is why you can not power a headphone with a rack amp or can't power your tower speakers inside your living room with a headphone amp.
A low-power amplifier is often fine.   Sometimes the same chips designed as low-power speaker amps are used to make headphone amps.   High-power amplifiers have too much output voltage and gain.   You might accidently blow-out your headphones/IEMs or your ears!   And the higher gain amplifies any background noise which is more noticeable with something next to, or inside, your ear.  

Well if you are sure that it is that simple, good luck with the cheapest amplifier you find in the market. I am pretty sure you will sound awesome. I don't even know how you come up with this. There are dozens of different guitar amplifiers and all of them sound different. There are different types of heads, with different transistors, different circuits and the "tube" amps which are renowned for their "warm" sound. You say just a single amp would be enough. No need for all this variety ha?

Re: Bluetooth, transcoding and audio quality

Reply #23 –
If you want to alter the sound - cf. how a guitar amplifier is part of a musical instrument to create sounds - then sure.
If you want to reproduce sound, then an amplifier is there to - wait for it - amplify. Being "a straight wire with gain", a quote attributed to QUAD's Peter Walker.

Sure there are operations that could very well sit in the same box as amplifier and even as speaker: active speakers with crossover (which are "extreme tone controls!") before amplification stage, or multi-speaker control for delay (again before amplification stage).

Re: Bluetooth, transcoding and audio quality

Reply #24 –
Quote from: lovecraft on
Well if you are sure that it is that simple, good luck with the cheapest amplifier you find in the market. I am pretty sure you will sound awesome. I don't even know how you come up with this. There are dozens of different guitar amplifiers and all of them sound different. There are different types of heads, with different transistors, different circuits and the "tube" amps which are renowned for their "warm" sound. You say just a single amp would be enough. No need for all this variety ha?
By previously bringing up monitor headphones and guitar amps into the discussion, you're actually undermining your own argument and avoiding the fundamental point: for everyday audio listening, amplifiers are primarily designed to, as faithfully  as possible, reproduce their input signal, just with increased power.

Besides, your taking the mick with "good luck with the cheapest amplifier [...] I am pretty sure you will sound awesome" - comes across not only as blasé, but also very audiophool-ilke, by recycling an old rhetoric o' theirs that we've heard a million times before.

Then "warm tube sounds"? 🤢
PUH-LEASE!!

Edit: sorry to the OP and others for actually veering this so off-topic. I promise I'll behave. ;)
• Listen to the music, not the media it's on
• The older, the 'lossier'