Which is the most difficult material to reproduce believably on hifi equipment?

Crack of a snare drum. What mecanical device could possibly replicate the sort of sound waves that come from a sharply struck snare?

Organ very true also. Brass bands not so sure. I always think they reproduce very believeably on my humble Planar3/72/Hi/140/Credo. And I played cornet for 15 years in one! -iii-0

Jonathan

A friend of mine (a pro jazz musician with a keen set of ears) reckons vibraphone to be the hardest instrument to reproduce convincingly. Don't know if it's the hardest, myself, but it's probably up there.

I heard a couple of pieces played on early pianos this evening. They sound so completely different to the modern concert piano that they are probably more like John's hifi. Or an old upright down at the pub! Plinky, plinkety plonk!

Nime

Further thought: Maybe this is two separate but related questions:

1. Which instrument is most difficult to capture accurately during the recording process?

2. Which instrument really tests the playback mechanism (assuming a good source recording)?

Find the sound that causes fits to recording engineers as well as playback engineers, and there's your winner.

PS- My favorite "instrument" - massed human voices - seems pretty amenable to believable playback.

You don´t need much listening to pipeorgans live to know that the sound of the lowest pipes (32f) - as Nime points out - never can be reproduced by any subwoofer or loudspeaker known. Neither as to frequency nor volume.
But the presence of the lowest partials is kidding us to think that we hear the deepest
sounds as well.

quote:

Originally posted by pe-zulu:
You don´t need much listening to pipeorgans live to know that the sound of the lowest pipes (32f) - as Nime points out - never can be reproduced by any subwoofer or loudspeaker known. Neither as to frequency nor volume.

What makes you think that?

Regards
Steve M

Well, I implied that the lowest sounds can´t be reproduced faithfully in a living room, partly because of the long wavelengths, partly as they are not sounding in a litteral sense, but rather booming. Have you never been in a church and sensed the reverbation in your body caused by the lowest pipes in a distance more than 40 meters from the organ? An orgen big enough to have 32feetpipes can´t be brought into a living room. But if you are Steve Margolis(?) you may know better.

Well, my view was:

quote:

...there's no way that you can get a realistic pipe organ with a bookshelf or small floorstander but if you have enough money you just need sufficient loudspeaker enclosure volume and/or amplifier power.

Nime's talking about a minimum of four 15" drivers in a manifold in the ceiling. I think you could do some damage with that but how about having four manifolds of four drivers each or eight manifolds? If you start to run out of sufficient volume to make an effective 'infinite baffle' type of speaker use some more drivers in 'isobaric' or 'compound' configuration to reduce the volume required. You'd just need more power, that's all. I'm sure you'd sense the vibration in your body.

I don't believe that it's easy but, if you're crazy enough, I think it could be done.

Pe-zulu, did you ever see photos of the crazies in Italy who made the cellar of their showroom into a massive bass horn? That must offer quite an experience.

Still, all this is just an opinion as I've never built such a system. I'd like to give it a try though.

Regards
Steve M

Even newer material !

quote:

Brass bands not so sure. I always think they reproduce very believeably on my humble Planar3/72/Hi/140/Credo. And I played cornet for 15 years in one! -iii-0

Maybe your musician brain/ear is filling in the gaps? For me hi-fi has never been able to vibrate the air (and the emotions)of that rasping live brass sound.

Goodnight Jez, a brilliiant observation and I'm personally wrecked at the moment, but I get your jist, Yes, a Brass Band full of Passion is hard to deny, though has also been known to sound pretty fair through the odd Yorkshire box or two, innit.

Fritz Von Bed really enuff² v Cheers

An interesting thing about brass band, for me, is that I generally listen to our's on a band-stand in the open air at our local fete. So there isn't much in the way of reverberation or reflections as you'd get in a hall.

Also, you can change the entire musical balance just by walking around the band-stand.

Regards
Steve M

Steve
Of course you know very much more about these matters than I do, but I find it interesting to hear, that it is at least theoretically possible to reproduce the sound of a large pipeorgan faithfully with loudspeakers. But in practise, I think, it would cost an astronomical amount of money, and you would need a large room (at least 250m2 with very high ceiling) to make it sound realistic. By the way an interesting supposition.
Regards

One of the great things about hi-fi design is that it's a field where lone mavericks can compete with the big boys (at the high end, at least). There's still plenty that is unknown. I have learnt to question every assumption that is made and most popular myths.

I don't know the truth about bass reproduction and room size (apart from resonant frequencies, nodes and antinodes that are related to the room dimensions). By this I mean that I really don't know. I've often read the view that you can't reproduce low notes in a small room but I question it. I've certainly measured bass in a small room and I think I've heard it or felt it. What about car stereos? Looking at the relative size of a car cabin, you might think that the reproduction of any note below 200 or 300hz would be impossible. This is clearly not the case, although cars are 'leaky' and this makes a difference (not that rooms are air-tight).

What about the inside of a speaker cabinet? This can be thought of as a very small room indeed. Yet, there's as much output from the rear of a cone as from the front. If there's no sound inside the cabinet below, say, 500Hz (taking the size of an average enclosure) does that mean that the cone movement is constrained at low frequencies or does it somehow 'cancel' itself out? If it's constrained, how is there output from the front of the cone?

If we took a church organ with one long pipe and had that pipe folded so that it fits into the ceiling of a room (the folding wouldn't affect things at low frequencies), would we hear the low notes in that room?

Has anyone out there got eight or sixteen 15" drive units of a suitable quality and a reasonable sized room? Let's play.

Regards
Steve M

quote:

Originally posted by 7V:
One of the great things about hi-fi design is that it's a field where lone mavericks can compete with the big boys (at the high end, at least). There's still plenty that is unknown. I have learnt to question every assumption that is made and most popular myths.

Very true and exactly how Naim started I do believe.

Steve

Maybee I was partly wrong in the start, writing that a speaker cannot faithfully reproduce the deepest sounds of a pipeorgan. Of course I implied that the listening-conditions were practical. I think of normal listening-rooms. But also I didn´t know that it is technically possible and not just teoretically possible to construct speakers going down to almost zero Hz. and being at the same time capable of yelding enough Watt. My actual knowledge in these matters is limited , but I shall try to explain why I think large rooms are neccessary.

When I listen to a recording of a harpsichord in my room, (one of those recordings with close miking), I think the sound is - almost - as I would expect if the proper instrument were present in my room. I do of course compare the sound in my room with the sound of similar harpsichords I have heard live. Harpsichords are usually built to sound in rather small rooms.

But when I in my room (18m2)listen to a pipeorganrecording the sound is not at all like how it was when the music was recorded (Here I compare the sound in my room with the sound of the organ in the church, provided I have heard the proper organ in that church).

And why not? My subwoofer can go down to at least 25 Hz. Of course some of the deepest bass is missing. And the sound pressure is too low, only two times 50 W. This is of course part of the explanation. If I theoretically got a subwoofer which could go down to one Hz and an amp up to say two times 1000 W if needed, shouldn´t that be OK then? Provided the loudspeakers were capable of reproducing it? I think still not. When an organbuilder makes the disposition of an pipeorgan and constructs the prospect, he builds the organ to the acoustics of that room in that very church, and the final result comes to light (or comes to sound - if you can say that) so to say as an interplay between the organ and the church. In my experience this problem is general but most true of the deepest sounds, which needs much room to sound free and natural, and you have to be at some distance of the sound to appreciate this. This is the reason why I think a large room is neccesary for lifelike reproduction of the sound of a pipeorgan as it was intended. You can add reverberation to the recording, but it will never be capable of sounding lifelike in my room. But you may say that it always is possible to construct speakers which reproduce the content of the recording 100pct. lifelike.

I own a Stax Signature headset, very fine with great compass and fine balanced sound, and the soundpressure reaching my eardrums may be put as high as to resemble the pressure I should experience if I listened in the church from a convenient distance, and certainly all the sounds are there, but the soundscape of the headset is completely unnatural. So the faithfull reproduction of e.g. a great pipeorgan is not just a question of compass and soundpressure, but also a question of acoustics.

Regards

With modern amps there is no difficulty in driving large subwoofers to very high SPLs at very low frequencies and low distortion.

My 12" driver subwoofer has a 350 Watt amplifier. It reaches 15Hz easily. Despite being a fairly low distortion reflex design and capable of high sound levels it still slightly lacks timbral definition on the larger organ stops in my 30 feet long room. Though it could be my 38Hz(-3dB)speakers adding their own distortion. The sub is certainly much cleaner (and impressive) at lower frequncies when heard alone.

Those who extoll the virtues of true infinite baffles consider these devices are capable of reproducing these lower frequencies with very low distortion. Enough to easily differentiate between the different stops. They are said to have a uniquely clean sound quality with remarkable dynamics.

It's all about moving air in large quantities. More and larger drivers lower the distortion levels and increase maximum SPL. These drivers must have a very long piston movement to work in a true infinite baffle. The rush for suitable drivers for car audio subwoofers has improved the availability of such drivers and reduced the prices to the easily affordable. Vmax should be 15mm minimum for 15" drivers. Spend enough money and you can have a couple of inches of cone travel these days.

Interestingly(?) in correspondance with a top subwoofer designer I learned that small rooms are easily pressurised and capable of supporting far louder anddeeper bass than a large room. Which went completely against my painfully slow learning of acoustics spread over several decades. Unfortunately I didn't learn what small rooms meant for bass distortion levels. (Perhaps I should ask)

Nime

24 inches;
Nearly 3 inches of excursion (but very little actually required);
1.6KW (IIRC);
4Hz in room;
One of a pair!

[BTW, Disney use a smaller version of this driver to simulate earthquakes at their theme parks.]

quote:

Originally posted by Martin Payne:
[BTW, Disney use a smaller version of this driver to simulate earthquakes at their theme parks.]

But presumably you've got a couple of larger versions as well, for more serious work.

Seriously, how is it on pipe organs?

Regards
Steve M

quote:

Originally posted by 7V:
But presumably you've got a couple of larger versions as well, for more serious work.

Steve,

LOL - noone who's met me could ever mistake me for the guy in that picture!

His main speakers went down to about 14Hz, -3dB. These were used mainly for AV duties. They weer really pretty incredible.

FWIW, He cracked a double-glazed window (not sure if the gless or the frame), and other minor structural mayhem with some ill-considered sine-wave testing.

cheers, Martin

Does he drive a blacked-up chav'd up Corsa ?

quote:

He cracked a double-glazed window (not sure if the gless or the frame), and other minor structural mayhem with some ill-considered sine-wave testing.

Of course...........that's what music is made for.
Does he use backstairs to change cds?

quote:

Originally posted by Nime:

The bass register is a matter of owning a decent subwoofer. Mine easily reaches 15Hz and will literally shake the house well below that.




Nime

Oh Nime, now I understand, why you are "in exile".

Venlig hilsen

I lige måde!

Mvh

Nime

(being rurally-detached is worth an extra 10dB and 5 extra Hz in any language)