Hifi on a boat

[pteron]

CD format is not lossless in the sense that with lossy formats parts of the recording are deliberately removed. However, any analogue signal, such as music, when converted to a digital format has to be sampled at a defined bit rate and purists will argue that the sampling of the analogue waveform is, in itself, a lossy process. Hence purists often still prefer vinyl discs!

The purists would be wrong. The analogue is band limited - perfectly possible to sample it and reproduce it without loss.

I love analogue, but such arguments are bull put about by people who don't know what they are talking about.

 

[noelex]

The purists would be wrong. The analogue is band limited - perfectly possible to sample it and reproduce it without loss.

I love analogue, but such arguments are bull put about by people who don't know what they are talking about.

The only way you can reproduce an analogue wave in digital form , without loss. would be to have an infinite sampling rate, which is not possible. So I think the purists have it right.
This does not mean, however, that an analogue record sounds better than a digital CD.

 

[prv]

I'm no expert but surely anyone producing vinyl these days would still be mastering from either analogue tape (as in the pre-digital days) or at least using very high sampling rate digital mixers which are much closer to an analogue waveform but would be unsuitable for direct CD pressing because of the huge file size?

I'm not in the business, but I doubt you would find a pro studio using analogue tape anywhere. When some of my mates had a band over ten years ago, all the studio stuff was on DAT tapes (digital) and that wasn't new by any means then. It's probably all on hard discs now.

Pete

 

[CreakyDecks]

The only way you can reproduce an analogue wave in digital form , without loss. would be to have an infinite sampling rate, which is not possible. So I think the purists have it right.
This does not mean, however, that an analogue record sounds better than a digital CD.

Not strictly true. The sampling frequency only has to be twice the maximum frequency of the signal. However, you need an infinite number of samples.

 

[grumpy_o_g]

OK, first things first. What actually matters are probably four factors. How good you think it sounds, the price, the reliability and the functionality/ergonomics/ease of use

The first three are fairly obvious, the last can be more obscure. Digital/analogue/CD/MP3?etc. should be decided by the criiteria - otherwise you're deciing you want diesel not petrol before you've driven it, or multi-hull not mono before you've sailed it.

The acoustics in the boat wil be appalling but they can be improved and you might be advised to spend money on wall facings, mounting structures for speakers, etc. You need to decide if you want perfect sound in one spot or to be able to listen throughout the boat. Often a good compromise can be headphones for the best sound and a more robust speaker set-up for listening around the boat. Car audio outfits (good ones) are skilled sound engineers who know the tricks of getting a half -decent sound in a bad room. You also need to think about formats and their availability, how you will purchase music and get it into your system, how you will control the system (some home hard-drive juke boxes are so unfriendly it's not true). Do you need controls in the cockpit? Will the system have to drive waterproof speakers in the cockpit at the same time as down below? Are you likely to want to expand the system to include say FM or DAB? What sot of music will you be playing? Do you want the system as quiet as possible outside the boat?

Get it done right and you can get a very high quality sound in your boat but you will be very lucky indeed to achieve that by just selecting components and bolting on.

 

[temptress]

We are putting together our boat as a liveaboard. We were initially looking at putting a car hifi in. However it occurs to me that we have the space to put in a 240v hifi and run it off the invertor.

Can anyone tell me the ballpark Ah to run this? Plus are there any downsides to this idea, if the unit is secure.

Many thanks.

Bit off topic - I would advise to try and minimize any use of an invertor. Once away from shore-power I find my biggest concern is battery capacity. Invertors are just too power hungry.


As for hi-fi - we have a good car hi-fi with a remote control, good speakers and quality wiring. we have the rear speakers wired up in the boat and are going to fit 2 water proof speakers in the cockpit as 'front speakers'. this works for us and gives us good sound. There are other ways of doing this, this works for us.

 

[pteron]

The only way you can reproduce an analogue wave in digital form , without loss. would be to have an infinite sampling rate, which is not possible. So I think the purists have it right.
This does not mean, however, that an analogue record sounds better than a digital CD.

As I said.

The analogue signal is both band limited - containing no information above 20 - 25 kHz and so can be completely reproduced by samples taken at twice the frequency (lookup Nyquist); and the amplitude information is limited by the noise in the system and so contains no information smaller than this.

The upshot of this is that it is possible to reproduce an analogue signal perfectly with a sufficient bit size and sample rate. Note I do not claim that CD has sufficient of either.

A 96/24 stream easily does however. It has a signal to noise of 144dB. The best amplifiers in the world have S/N of around 112 dB. The digital stream is orders of magnitude better than needed as the analogue content has long since disappeared into the noise floor.

 

[noelex]

As I said.

The analogue signal is both band limited - containing no information above 20 - 25 kHz and so can be completely reproduced by samples taken at twice the frequency (lookup Nyquist); and the amplitude information is limited by the noise in the system and so contains no information smaller than this.

The upshot of this is that it is possible to reproduce an analogue signal perfectly with a sufficient bit size and sample rate. Note I do not claim that CD has sufficient of either.

A 96/24 stream easily does however. It has a signal to noise of 144dB. The best amplifiers in the world have S/N of around 112 dB. The digital stream is orders of magnitude better than needed as the analogue content has long since disappeared into the noise floor.

Nysquist theorem is a mathematical model, it is recognized that for real world signals applying Nyquist formula does not result in perfect reproduction.
It also requires an infinite number of samples, and that is not going to fit on any music source available now, or in the near future.

24 bit recording do sound great however and are way better than vinyl to my ears

 

[concentrik]

.

One factor which I think is very important - speaker mounting. Many people will purchase a pair of chassis drive units - the bare speakers- then mount them in the most convenient flat bulkhead or locker face with the back of the speaker open. This type of driver is designed to be mounted in an infinite baffle, or speaker cabinet/box (the familiar speaker enclosure) so that the back of the unit is in an airtight box. Well, it might not be airtight if it's a folded horn / ported design or something like that but they'd be a bit greedy on space for most situations. Distortions and anomalies produced by the speakers far outweigh any amplifier/media considerations, so I think as much effort as possible should be applied to this area. It won't be, of course, because it would often involve huge effort moulding a shaped enclosure. If you want to experience the most accurate reproduction get some headphones [waits for incoming...]

One important distinction to bear in mind when considering sound quality - different and better are not the same thing!

Slightly off topic but still worth a laugh is:

http://www.belt.demon.co.uk/

Some forumites may recall the almost religious fervour which accompanied this blokes proclamations a few years ago, aided and abetted by the HiFi press. Accolytes across the world froze their CDs, painted the edges with green dye and checked piles of magazines in their 'listening areas' to make sure there were an even number of pages. Gradually people noticed that the emperor was somewhat under-dressed.....

 

[pteron]

Nysquist theorem is a mathematical model, it is recognized that for real world signals applying Nyquist formula does not result in perfect reproduction.
It also requires an infinite number of samples, and that is not going to fit on any music source available now, or in the near future.

24 bit recording do sound great however and are way better than vinyl to my ears

Where does this infinite number of samples bull**** come from? Have you studied any higher mathematics?

If your analogue signal had infinite bandwidth it would contain infinite power. Where are you going to get the electricity to drive that?

 

[nigelmercier]

I'm no expert but surely anyone producing vinyl these days would still be mastering from either analogue tape (as in the pre-digital days) or at least using very high sampling rate digital mixers which are much closer to an analogue waveform but would be unsuitable for direct CD pressing because of the huge file size?

While I can't claim to be an "expert" I was in the TV industry for 30 years. The equipment is similar to recording studios: analogue went out years ago, and the digital equipment uses only a very slightly higher sampling rate; more to ensure non-compatibility with domestic equipment than any obvious technical benefit.

Sure, vinyl sounds different; but this is because of the massive amounts of pre-correction applied to the waveforms. Those who say vinyl is "better" are really saying it's not what they are used to; or they are just nutters. One of my best mates is one such nutter, he has gold-plated mains fuses in his power amplifier!

 

[noelex]

Where does this infinite number of samples bull**** come from? Have you studied any higher mathematics?

If your analogue signal had infinite bandwidth it would contain infinite power. Where are you going to get the electricity to drive that?

Perhaps we better agree to disagree. I am sure Harry Nyquist will be looking down from that infinite place amazed that we are discussing his theories on a sailing forum.

BTW I have studied higher mathematics, I was even taught how to add up and subtract without using my fingers and toes.

 

[AntarcticPilot]

The only way you can reproduce an analogue wave in digital form , without loss. would be to have an infinite sampling rate, which is not possible. So I think the purists have it right.
This does not mean, however, that an analogue record sounds better than a digital CD.

But the band-width of the analogue equipment is necessarily limited; at the top end it doesn't go far beyond the sensitivity of a good ear. As long as the digital sampling exceeds the Nyquist criterion for the band width of the analogue signal, then there is no loss whatsoever. And it is very easy to satisfy the Nyquist criterion. As far as I know, the CD sampling rate was deliberately chosen to reproduce analogue signals in commercial use (i.e. recorded on the best quality vinyl), so CDs reproduce the vinyl recording without loss, and without the introduced surface noise of a vinyl recording.

Incidentally, the master tapes are very effectively band-limited - the bias frequency applied to the tape sets an absolute upper limit for the frequencies to be recorded.

Some of people's preference for vinyl is that they have got used to the way it sounds - because the vinyl medium does not have a flat response curve itself,you shouldn't expect it to be as good a reproduction of the sound of the original music as a CD is.

On a boat, or even in the average living room, this is totally academic, as no-one listening in these conditions will be able to tell any difference at all.

I'll join in the vast crowd saying get decent speakers; the rest doesn't much matter.

 

[pteron]

Perhaps we better agree to disagree. I am sure Harry Nyquist will be looking down from that infinite place amazed that we are discussing his theories on a sailing forum.

BTW I have studied higher mathematics, I was even taught how to add up and subtract without using my fingers and toes.

Perhaps we should.

His theorum has been proven. It is not a theory. There is a difference.

 

[nigelmercier]

Some of people's preference for vinyl is that they have got used to the way it sounds ... I'll join in the vast crowd saying get decent speakers; the rest doesn't much matter.

Exactly my point above.

In fact on a boat, even half-decent speakers are OK; the acoustics of the space are not ideal!

His theorum has been proven. It is not a theory. There is a difference.

Not that much of a difference, both are proven. A theorem is a statement that has been proven on the basis of previously established statements, such as other theorems. A theory has empirical proof, such as gained by means of observation or experimentation. [Source Wikipedia]

 

[Conachair]

Sure, vinyl sounds different;

Now it's been a long long while, but I can't remember being able to hear the bass drum pedal squeak on "Since i been lovin you" on Zep 3 back then on vinyl. Very obvious on cd. Is it so obvious on vinyl?

 

[Stu Jackson]

we have the rear speakers wired up in the boat and are going to fit 2 water proof speakers in the cockpit as 'front speakers'. this works for us and gives us good sound.

Uhm, wouldn't you want to have the front speakers be in the cabin and the rear speakers be in the cockpit?

And along those lines, my wife strongly suggested that the record player for the vinyl wouldn't work on starboard or port tack too well, maybe only going downwind.

 

[noelex]

Now it's been a long long while, but I can't remember being able to hear the bass drum pedal squeak on "Since i been lovin you" on Zep 3 back then on vinyl. Very obvious on cd. Is it so obvious on vinyl?

One trouble with vinyl is that you need a very good quality turntable for even reasonable sound. A $100 CD player will always beat a $1000 turntable, but spend around $5000 + on a CD player and turntable there are those (certainly not everyone) that prefer vinyl.
As CD players and technology is improving the numbers in the vinyl camp are dwindling

 

[theoldplucker]

A good loudspeaker can make the sound worse. The speaker is the least important part of the chain. The source is the most important. Rubbish in - rubbish out. The order, with vinyl, is turntable first, then pick-up arm, cartridge, amplifier and finally speakers.
Of course the quality of the recorded material itself is most important. Sadly in recent years recording quality is abysmal. Far too much compression is applied at the studio. Compressed even more on mp3 and when broadcast. Compression kills music and makes it exceedingly boring to listen to. Google 'loudness wars' for more information.
Many 'remastered' versions are far worse than originals.
As for vinyl, as I understand this is increasing in popularity, especially with the youngsters.

 

[RichardS]

Now it's been a long long while.....

it's been a long time, been a long time, been a long lonely, lonely, lonely, lone-ly time!

Richard