Why do bass drivers go nuts when playing vinyl [Archive] - Audio & Video Forums

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TerryB
02-28-2005, 02:30 AM
whereas with exactly the same piece of music on CD, they hardly move, even though the resultant sound *seems* the same? Never understood why this happens - anybody?!

markw
02-28-2005, 02:38 AM
whereas with exactly the same piece of music on CD, they hardly move, even though the resultant sound *seems* the same? Never understood why this happens - anybody?!The turntable itself produces a lot of very low, high level, sometimes inaudiable frequency mechanical rumble that's transmitted thru the tt itself, through the cartridge anf finally to the amp where it sucks up a lot of amplifier power moving those speakers. That's what rumble filters are for.

Second, feedback. Sound generated from thespeakers is picked up by the TT and cartridge and amplified over and over again. Sometimes, if you play it to loud it can break out in a howl. In thjis case, decopuling the TT from the speakers can help tremendously.

TerryB
02-28-2005, 04:47 AM
I see! So why isn't there a similar mechanical rumbling noise from the transport of a CD player, or is this totally different?

Is the presence of this noise an indication of an inferior turntable, or do they all do it?

cheers

markw
02-28-2005, 05:08 AM
Tt's depend on a needle wiggling in a groove and generating an analog electrical signal in a cartridge. If something makes that needle wiggle, it will get amplified. A CD player relys on light reflecting off of a surface and producing a stream od on/off pulses

As such, you can pretty much walk with 'em and have not too many problems. Granted, a skip buffer is needed to assure the continus delivery of the signal under physicaly demanding conditions but on the whole they are pretty immune from physical vibration infecting the signal chain.

All TT's have some rumble. The better the turntable, the less rumble it will have.

E-Stat
02-28-2005, 05:17 AM
Is the presence of this noise an indication of an inferior turntable, or do they all do it?
No, they do not all do it. Modern units are dead quiet and generate very little rumble. Isolation devices are used to address mechanical feedback.

rw

TerryB
02-28-2005, 05:50 AM
So should i look to eliminate this rumble? My tt playback quality really is on a par with my CD, at what is really a fraction of the cost! I just can't live with the surface noise and lack of direct access unless i'm having an enthusiastic hour or so with the 12" singles! Would i notice a difference at the speakers if this rumble was minimised?

shokhead
02-28-2005, 07:19 AM
You answered your own question.

markw
02-28-2005, 07:29 AM
We've obviously transversed from a speaker to a vinyl issue. Vinyl is still a viable alternative but there some inherent issues that you must learn to live with.

No matter what TT you have, there will always be some surface noise and, aside from an ancient ADC turntable, I can't think of any that will address your direct access issues.

And, the statement that new TT's are deas silent is a bit of an exaggeration. While rumble can be minimized, it's always there. Please note that he qualified that statement in the next sentence. Also, please be aware that certain speaker designs and placement in the room can accentuate this cone movement situation. Ported speakers tuned to a low frequency are a good example of this.

You also might inquire as to the costs of some of these "dead silent" turntables some people refer to.

dean_martin
02-28-2005, 08:33 AM
check out the "cone flap" thread in the analog forum started by dba and the link to another thread posted by royphil in response.

E-Stat
02-28-2005, 09:25 AM
And, the statement that new TT's are deas silent is a bit of an exaggeration.
Unless you are referring to an idler wheel driven changer, I stand by my comments. It doesn't take a $10k turntable to be free of mechanical noise audible by the average system. My 30 year old Ariston RD-11s still fits that bill. You will only hear the motor if you place your ear within inches of it. There are any number of inexpensive DIY isolation tricks around using bicycle tire innertubes and maple butcher blocks that address what is the more likely cause of most folks' problems. I use a twenty year old VPI HW-1 isolation base.


You also might inquire as to the costs of some of these "dead silent" turntables some people refer to.
You can get a new Rega for about $500. Indeed my new VPI Scout runs twice that without tonearm. Better still, you can buy a used Rega, Thorens, Ariston, Music Hall etc. turntable for less. There is a Thorens TD-160 on Audiogon now for $200. Here's a website devoted solely to Thorens:

http://www.theanalogdept.com/thorens_gallery.htm

rw

RGA
02-28-2005, 10:28 AM
Turntables are the fussiest things you can buy in audio especially for people like myself who grew up on cd. I'm overly painfully careful with the turntable -- I had it about a year before I got it fixed err set-up correctly. Yes there is some surface noise on some Vinyl and some where there is practically zip. The trade-offs trounce either cd player I own.

A record cleaning machine supposedly greatly reduces and or eliminates surface noise and gritty sound between songs and will be my next purchase because I bought a pile of used vinyl cheap but some are quite dirty.

I have found the differences between vinyl and cd not as great with some systems that are designed for the cd SS crowd...and the phono stage makes a massive difference which I did not expect to be the case.

CD has it's own forms of distortion that is called jitter which gets bypassed - corrective feedback to highly process and re-integrate the sound. CD is the main standard and it's awfully hard to detect its faults when there is little to compare it against. I suggest you listen head to head a typical high error correcting cd player with many times oversampling and an Audio Note cd player that has no error correcting or fixing. The fixing players will look prettier on the graph but listen to em side by side. This will illustrate that what is being measured most of the time is meaningless. Putting a wow and flutter number on cd players is and was merely a marketing tool.

Vinyl isn't going anywhere and there is good reason for this.

markw
02-28-2005, 02:25 PM
that when I saw RGA's moniker that somehow AN would be talked up.

Jeez, guy. Do you get a spiff or what?

Careful, you're becoming a charactiture of yourself. And nobody takes them seriously.

risabet
02-28-2005, 03:26 PM
The turntable itself produces a lot of very low, high level, sometimes inaudiable frequency mechanical rumble that's transmitted thru the tt itself, through the cartridge anf finally to the amp where it sucks up a lot of amplifier power moving those speakers. That's what rumble filters are for.

Second, feedback. Sound generated from thespeakers is picked up by the TT and cartridge and amplified over and over again. Sometimes, if you play it to loud it can break out in a howl. In thjis case, decopuling the TT from the speakers can help tremendously.

A properly designed and maintained TT does not produce any audible rumble. In all likelihood, the cause of your problem is infrasonics caused by the arm/cartridge resonance frequency. This can be aggravated by record warps or an improperly matched cartridge/tonearm but any modern table shouldn't rumble audibly. In my opinion there is no comparison between well done analog and CD, analog wins every time.

Woochifer
02-28-2005, 05:08 PM
The issue with vinyl is exactly as markw described. Low frequency rumble is pretty common with vinyl playback, no matter how good the isolation is. Some of it is mechanically induced, but some of it also originates with the vinyl pressing itself. Off-center holes, less-than-flat LPs, surface irregularities, bad mastering, etc. can all contribute.

The thing about the vinyl rumble is that a lot of it occurs in an inaudible low frequency range. With ported speakers, this often occurs below the tuned port frequency, so the cone movement is undampened in that range and might look worse than it actually is (you get a lot of movement, but it won't produce any audible effects aside from possibly reduced coherency in the higher midbass and midrange frequencies above the port frequency).

If you look at older receivers and preamps, you'll note that a lot of them have subsonic filter switches on them. Those switches were put in place because of how common the subsonic rumble was with vinyl playback.

RGA
02-28-2005, 06:23 PM
that when I saw RGA's moniker that somehow AN would be talked up.

Jeez, guy. Do you get a spiff or what?

Careful, you're becoming a charactiture of yourself. And nobody takes them seriously.

markw the problem is that Audio Note does do some things that few others do and innovated some things no others do and those hwo copied are not reciognized as doing it as well. I was attemptuing to defend the cd format, albeit badly, by mentioning their player as one to audition which takes down some of the complaints against cd. It is easiest to discuss products I am more familiar with than merely provide a generality.

It is also helpful to note that a lot of the assumptions about cd replay can easily be disputed with a simple audition. Their players should have a lot of busrt errors, jitter, skipping among a few other things not coming to my head at the moment -- and yet none of this happens. Trusting a common approach isn't nevcessarily the rioght approach. From my own personal listening and I grant you I am perceived as being biased -- Their cd players are A the best ones I've heard and B) probably the best ones vinyl lovers are going to like as well judging by the vinylphiles I've met in person and on forums. Their cd players after all was created by a vinylphile for himself...and some other folks liked it and boom people started buying em.

Pat D
02-28-2005, 07:42 PM
whereas with exactly the same piece of music on CD, they hardly move, even though the resultant sound *seems* the same? Never understood why this happens - anybody?!
Actually, the cause is quite probably the resonances caused by record warps on a tone arm and cartridge combination which have a resonance in the record warp range. If this is a problem, there are cartridges with a damper that looks like a brush.

As has been explained, when you have a speaker with a woofer which is undamped at such low frequencies (woofers audgmented by a port or passive radiator), there is nothing to keep the driver from moving back and forth to a considerable degree. It can muddy the music if severe enough. Remedies include a rumble filter or a better tone arm cartridge combination.

Low frequency feedback in the room can cause this, too. As has been mentioned, better isolation of the turntable may help, often just moving the turntable farther from the speakers--but that won't cure the above problem.

Peter Duminy
02-28-2005, 07:59 PM
Risabet and Pat D are right IMHO, as many of the vintage amps like Quad for example, had a "Rumble Filter" on them. Most had a rolloff of 12dB/18dB below 18Hz - 15Hz depending on the model. They were very effective too. Fitting very high compliance cartridges in high mass tonearms with even slightly warped discs will give your woofers a workout they have never seen before! ;)

BRANDONH
03-01-2005, 10:38 AM
If you look at older receivers and preamps, you'll note that a lot of them have subsonic filter switches on them. Those switches were put in place because of how common the subsonic rumble was with vinyl playback.

Intresting.
My amp has a subsonic filter switch on it. I have never used it because the manual said it could make the bass sound rubbery I only use the clip limiters.
But I am going to try switching it on and see If I can hear a difference when I am playing back Vinyl.
Thanks

:cool:

BRANDONH
03-01-2005, 10:49 AM
whereas with exactly the same piece of music on CD, they hardly move, even though the resultant sound *seems* the same? Never understood why this happens - anybody?!

One day a friend of mine came over with a Rolling Stones "Some Girls" CD and I had it on the original Viny LP (before they removed the famous actors from the cover).
Anyway I popped in the CD and put the record on at the same time with both playing the same song I switched between the two and wow what a bass difference!
The vinyl blew away the bass reponse of the CD in fact it sounded altogether better that the CD my friend was amazed.
Long Live Analog.

Woochifer
03-01-2005, 12:35 PM
Turntables are the fussiest things you can buy in audio especially for people like myself who grew up on cd. I'm overly painfully careful with the turntable -- I had it about a year before I got it fixed err set-up correctly. Yes there is some surface noise on some Vinyl and some where there is practically zip. The trade-offs trounce either cd player I own.

Be very careful about the generalizations. The advantages of vinyl playback are more of a case by case proposition. The quality of the mastering, the quality of the pressing, remasterings done at different times, the compression and EQing that get applied to the recording, etc. vary a lot more with vinyl. Even with the same album, you'll get variations between pressings because of worn stampers, changes to the vinyl (formulation, thickness), etc. CDs are for better or worse consistent from disc to disc, and nowadays, the variations in the quality of the mastering are narrower than before.


A record cleaning machine supposedly greatly reduces and or eliminates surface noise and gritty sound between songs and will be my next purchase because I bought a pile of used vinyl cheap but some are quite dirty.

Record cleaning machines are effective at maintaining albums, but won't work miracles for used and abused LPs. A lot of what you hear on vinyl is simply wear and tear or bad pressings, and nothing can be done about that.


I have found the differences between vinyl and cd not as great with some systems that are designed for the cd SS crowd...and the phono stage makes a massive difference which I did not expect to be the case.

Huh? So what systems are NOT designed for "the cc SS crowd"?

The phono stage makes all the difference in the world because it has to apply the RIAA equalization and step up the signal to line level.


CD has it's own forms of distortion that is called jitter which gets bypassed - corrective feedback to highly process and re-integrate the sound. CD is the main standard and it's awfully hard to detect its faults when there is little to compare it against. I suggest you listen head to head a typical high error correcting cd player with many times oversampling and an Audio Note cd player that has no error correcting or fixing. The fixing players will look prettier on the graph but listen to em side by side. This will illustrate that what is being measured most of the time is meaningless. Putting a wow and flutter number on cd players is and was merely a marketing tool.

So are you saying that jitter causes audible distortion?

Once again, you're parroting Peter Q's rantings against "conventionalists". Your observations are flawed because you have no clue as to what the true causal variables are. No error correcting or fixing? I thought that error correction was built into the CD standard so that the player could still play through fingerprints or minor scratches on the surface. Error correction and oversampling are two different concepts. Just the way that you use them interchangeably doesn't speak well for your knowledge of the topic independent of whatever you read from Peter Q. It's fine to have a preference, but you've gotten into a habit of claiming that every other approach is therefore inferior, without even knowing anything about those approaches or if they're even the actual causal variable behind the differences that you're hearing.

As for oversampling, the original Sony CDP-101 had no oversampling or digital filtering, and it sounded horrible. If you think that's such a superior approach, why not grab one of those from a local antique shop? From my own listenings, even a $20 portable CD player is preferable.

Maybe you should find one of those models and compare THAT to the AN. If they sound similar enough, then maybe indeed it is the oversampling that you're detecting. But, if they sound very different, then you need to pay attention to other causal variables. In my listenings, the most audible differences between CD players often have more to do with the analog circuitry than at the digital end.

And how do the "fixing" players differ from the ANs "on the graph"? You're always talking about "the graph", well which "graph" are you talking about? Sounds like more rhetorical exaggerations are on display here, or just another excuse for you to say "prettier."

Do you actually know what wow and flutter sound like? When comparing analog components such as turntables or reel-to-reels or tape decks, you'd damn well better pay attention to the wow and flutter because the differences are often very audible. With CD players, wow and flutter is not an issue because they tend to measure almost identically, and audibly speaking, wow and flutter are not problems with the CD format. How would that be "merely a marketing tool" given how differences in wow and flutter are audible with analog equipment?

Woochifer
03-01-2005, 06:51 PM
Intresting.
My amp has a subsonic filter switch on it. I have never used it because the manual said it could make the bass sound rubbery I only use the clip limiters.
But I am going to try switching it on and see If I can hear a difference when I am playing back Vinyl.
Thanks

:cool:

The subsonic filters only kick in well under 20 Hz. You won't have a lot of material that extends into that range, so I doubt that it would make for "rubbery" sounding bass.

Like I said, they were primarily put in because of how common that low frequency rumble is with vinyl playback. It was primarily put in place to protect speakers from overexcursion and to save the amp from having to drive those low frequencies. It's not supposed to have an audible effect aside from whatever comes through saving your speakers and amp from doing all that extra work.

E-Stat
03-01-2005, 07:55 PM
The subsonic filters only kick in well under 20 Hz. You won't have a lot of material that extends into that range, so I doubt that it would make for "rubbery" sounding bass.
Actually, he uses a pro amp with a 50 hz low frequency filter as well. Has clip limiters, too.

When was the last time you saw a rumble filter on a modern phono preamplifer?

rw

RGA
03-01-2005, 10:18 PM
Okay this is my third time trying to post this so I give up... An's design on cd can be seen on the net --- for complete and correct stance look there rather than me trying to reduce it simply -- why - it's merits are out there already listed - they don;t use any digital filtering and they are direct from disc designs -- they sound nothing like the opriginal players.

I was not saying either or with vinyl or cd -- some albums you can only get on vinyl - I listen to cd just as much as vinyl. My sample size is random I feel enough to warrant my inkling that unless the vinyl is damaged or was a poor print it has thus far for me been superior to the same album on cd. Even if one wants to believe it is the cd recording process that is at fault still makes no difference because if the giood version is on vinyl then it's the technology you NEED to have to get the better sound.

This is also why we need Redbook CD and the reason Peter built a cd player in the first place because a lo9t of music he loved was ONLY being preserved on cd -- to hear it he needed a cd player -- only to him they all sucked --- so he went out to make it better...whether one agrees with it or not can simply be auditioned.

BRANDONH
03-02-2005, 08:51 AM
Actually, he uses a pro amp with a 50 hz low frequency filter as well. Has clip limiters, too.

When was the last time you saw a rumble filter on a modern phono preamplifer?

rw

My unit does both 20 or 50 Hz which one should I choose?

LF filter freq. select (20 or 50 Hz)

Woochifer
03-02-2005, 11:33 AM
Actually, he uses a pro amp with a 50 hz low frequency filter as well. Has clip limiters, too.

And that would not be a subsonic filter (at least the kind that I was describing) because it cuts off the frequencies well into the range where you still get content that's part of the source. The switches that I was describing only kick in where the signal content is primarily limited to low frequency noise.


When was the last time you saw a rumble filter on a modern phono preamplifer?

Subsonic filters were never limited just to phono preamps. Integrated amps and two-channel preamps have frequently incorporated the feature; though not as common nowadays since the filters were frequently part of same signal path as the tone controls, and the general approach nowadays with two-channel is eliminate any signal altering switches. Conrad-Johnson and Accuphase are a couple of the manufacturers I've seen that currently make preamps with switchable subsonic filters on board. And nowadays, the feature is very common with subwoofer amps and mobile audio equipment.

risabet
03-02-2005, 12:51 PM
My unit does both 20 or 50 Hz which one should I choose?

LF filter freq. select (20 or 50 Hz)

Neither, a 20hz subsonic filter will phase shift the signal well into the audio band and the 50hz is not even worth discussing if you want to hear any bass. The best cure for your problem is a well matched tonearm and cartridge on a decently designed TT.

BRANDONH
03-02-2005, 01:37 PM
Neither, a 20hz subsonic filter will phase shift the signal well into the audio band and the 50hz is not even worth discussing if you want to hear any bass. The best cure for your problem is a well matched tonearm and cartridge on a decently designed TT.

Thanks,
I think I'll leave it switched off I really have not noticed any problem what so ever with my vinyl play back. But the earlier post got me curious about the switches.
The manual does not go into much detail about the filters other than It could protect the woofers but may cause the bass to sound rubbery.