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Auricauricle
10-12-2008, 03:08 PM
A recent post I composed described various experiments that I performed on a Yamaha (DSP A-2070) integrated amplifier that I was using for awhile, until I decided my ears were equally happy with a much less assuming Sherwood (R-525) A/V receiver which now occupies the audio cabinet. We live in a rather small apartment, and have had to make various adjustments to make more space available for the various accoutrements that I have acquired in previous years, and stashing the stereo gear into a large Biedemeyer wardrobe trunk is a sacrifice that was not eagerly embraced. I am a man of peace for the most part, but when it comes to my gear, I can get ornery. When my wife insisted that the gear be so stored and that my loudspeakers be placed atop the cabinet, I was deeply hurt. At the time, I owned a very nice Citation 5 tube amplifier and a few other fancy, schmancy things that I wanted to enjoy and show off. In the end, discretion won out, and that is the way it will remain until we move into a bigger apartment or someone has a most unfortunate “accident”.

The experiment that I am talking about involved turning the front speaker attenuators of the Yamaha to the negative, past flat: a step that was in my mind counterintuitive. Although I am quite familiar with sound, my almost compulsive need to tweak and fiddle took the best of me one evening and I found myself aware that the speakers I was listening to (Polk Monitor 7c) were a bit forward in their presentation. As I turned the volume down, I noticed that the perceived placement of the speakers actually descended. By the time I reached a certain point I realised that they had left their perch near the ceiling and sounded as though they were right in front of me--at ear level! To compensate for the diminished volume, as the master volume knob was cranked up, the frontal speaker controls locked in place, an adjustment that continued to give me the sense that the speakers remained in their respective “perceived” places.

Because we live in such a modest abode (okay, and because I am a tweakaholic), I have bought a couple of equalizers that have been employed to help shape the sound of the music I listen to and to assist in compensating for that which the limitation of space imposes. One of them is the Audio Source Architect, a rotary-dialed graphic equalizer that was originally designed for in-wall speaker users who wanted something to maximize their use. The other is a parametric equalizer, an SAE E101, a "computerized " unit that stores ten settings of level, bandwidth and frequency.

Psychoacoustics tells us that amplitude and volume are interrelated but not directly proportional. In other words, a wave that is produced corresponding to a middle C is perceived as louder than a wave that is produced corresponding to a C two octaves lower. This makes sense: when one listens to a music score or watches a movie that involves the use of a subwoofer, the mighty speakers are not heard in uniform correspondence to the higher pitched material. Imagine how horrible it would sound! Instead, some notes are perceived more readily than others. This relationship was made clear in 1933 by Fletcher and Muson, whose despictions of equal loudness contours graphically describe the phenomenon (http://en.wikipedia.org/wiki/Psychoacoustics).

In using the equalizers I have sought to take this knowledge into account and allow the waves that are translated by the speakers a chance to develop somewhat differently than they would if they were allowed to be presented in an unfettered state. Until the experiment was performed, this meant making adjustments that involved clocking the controls to the positive. Intuitively, this made sense. The more directionally positive I turned the controls, I reckoned, the more sound—and satisfaction--I would get. Likewise, clocking backward into the negative territory meant—I reckoned again—subtracting from the musical experience detrimentally.

Remembering my experience with the Yammy, and having way too much time on my hands, I approached the SAE’s controls a bit differently the other day. As previously mentioned, the equalizer has a few controls that are used in shaping sound, among them controls for frequency, bandwidth and level. Until this point, the controls have been turned to the positive end of the spectra, producing satisfactory but fairly predictable listening characteristics. Yet, as I turned the level controls back, I noticed that subtle details popped out of the speakers that I had not expected. In fact, imaging and separation became noticeably improved and by the time the controls were well “to the left” in negative territory, the sound of the speakers I have been listening to was markedly different in quality than before.

I suppose--and fellow readers and physicists, if I am wrong, please correct me--that in turning the controls back, I have created a psychoacoustic equivalent of simulating the full expression of waveforms that would be heard if the space that I had for doing so were to be realized. In so clocking back the controls to less than flat, bass notes are given full bloom and midrange and highs are produced with a bit more clarity and with a little more restraint. I do compensate somewhat in clocking the graphic EQ’s controls a slightly to the positive, thinking that the parametric’s bandwidth control allows me to do so while keeping it all in check.

In sum, while I am listening to music in a way that sounds very pleasant but employs using my equipment in a fashion that is only beginning to make sense. Instead of turning the controls to the usual positive direction, many of them have been set back into the negative, past flat response. In doing so, the waves (as I understand things) are allowed to be produced in their psychoacoustic fullness—much like using a compander of old that allowed loud passages to be made a little louder and the softer passages softer to be reproduced in an exaggerated albeit unexpectedly and pleasantly.

...Anyway, such were the thoughts that came to me this afternoon as I was staring out the window this afternoon and wondering whether the rain was going to let up or I should practice treading water (sorry, BC).

pixelthis
10-12-2008, 09:36 PM
huh???

Feanor
10-13-2008, 05:07 AM
....

Remembering my experience with the Yammy, and having way too much time on my hands, I approached the SAE’s controls a bit differently the other day. As previously mentioned, the equalizer has a few controls that are used in shaping sound, among them controls for frequency, bandwidth and level. Until this point, the controls have been turned to the positive end of the spectra, producing satisfactory but fairly predictable listening characteristics. Yet, as I turned the level controls back, I noticed that subtle details popped out of the speakers that I had not expected. In fact, imaging and separation became noticeably improved and by the time the controls were well “to the left” in negative territory, the sound of the speakers I have been listening to was markedly different in quality than before.

...

Well, in so far as I follow what you're saying, the simple explanation is that SAE was being overdriven at the higher gain, "positive" settings and the "negative" settings are improving the dynamics and general clarity.

Also, these old parametric equilizers did bad things to signal phase which can only degrade the sound. Your best strategy is take that piece of junk and hurl it into the nearest dumpster. .

Auricauricle
10-13-2008, 05:28 AM
That's an interesting hypothesis, but I wonder if it is a simple matter of a keener sense of adjusting the parameters for the room. While larger rooms may benefit from turning to the positive, smaller rooms require more judicious, negative-direction singnalling to get the maximum benefit.

One thing you can tell me if you know, this unit and/or the subwoofer produces a lot of RF that is emitted in the cables. I use chokes and try to separate the cords from each other as far as possible, but still have to pare and pull at times to clear up the signal. Is there an inexpensive, handyman solution available or am I gonna have to wait until I get a proper rack?

Thanks again for the feedback...er, reply.

Mr Peabody
10-13-2008, 06:43 AM
I'm not sure if frequency response effects the length of a sound wave but you are correct that sometimes you can do better by turning a tone control down opposed to up. Even though they go both up and down from center, turning down doesn't seem to occur to most people. A lot of times turning the tone control up too much will tax the receiver's amp.

Feanor is correct as well that many times EQ's do introduce more noise and distortion. You should try taking them out of your system to see if you still have your RF noise problem. If so, you could try a power conditioner product to see if it eliminates it.

My question out of your entire dialog, if space is your excuse for packing away the "good stuff" and listening to a "cheezy receiver" then why in the hell did you make room for two EQ's? It would seem if you had that much room to spare just listen to the good stuff :)

Auricauricle
10-13-2008, 07:02 AM
At this time, the only amp I have is the receiver. Pulling the cords and interconnects away from each other has eliminated RF, but every now and then the beast rears his head and to the back of the gear I return to check out the connections and pull a cord here and there to put him back in the lair. Gets old after awhile. Think you're right, though: will need to get a good power conditioner, and replace the cheapo power strip.

Unfortunately, much of the "good stuff" I owned at one time has had to be sacrificed to Ra. Once I become employed and more financially solvent, I will obtain more "interesting" gear. In the meantime, the Sherwood/Newcastle is really not at all "cheesy"; it's very pleasant and was an excellent deal...

NP: Klaus Schulze 72-93: the essential

Mr Peabody
10-13-2008, 08:18 AM
You might also try some better interconnects which will also require additional funds, something like Audioquest, Tributaries or even Bluejeans, just something that has good shielding and quality.

Sherwood has always been extreme entry level, 5,000 wpc x 7 @ .00003% THD (translated 5 wpc x 7 @ 3,000% THD) for $89.99. With that being said, I have not seen or heard the stuff since they became affiliated with Newcastle. I heard they had a receiver at Best Buy for cheap which didn't do anything to change my opinion of them but other than that I haven't seen any around. I had a friend who used to sell their car audio. He said it was cheap but held together pretty well.

Any way I think most of us have used gear that wasn't top shelf and we had to start some where, or make do until a situation has improved. My first real audio system was a Realistic receiver and some off brand 12" 3-ways put out by Pioneer but they wouldn't even put their name on them. Anyone heard of Centrex? It rocked me at the time though.

E-Stat
10-13-2008, 09:11 AM
The experiment that I am talking about involved turning the front speaker attenuators of the Yamaha to the negative, past flat: a step that was in my mind counterintuitive.
A more simplified observation is that equalizers of all flavors work best when used as attenuators. Mild boosting is fine, but large swings will cause many to ring. The Fletcher-Munson loudness curves are well known to substantiate the need for boosts at the bottom and smaller ones at the top when playing at reduced levels.

rw

Auricauricle
10-13-2008, 09:36 AM
True enough points from both of you....I wouldn't deign to compare S/N equipment with more elite brands, but as a solid, consumer-based brand, it holds its own. Still, as regards attenuation, I could be full of it; seems the more familiar I become with the medium, the more ignorant I find myself.

I reckon that's life, eh?

pixelthis
10-13-2008, 10:08 PM
True enough points from both of you....I wouldn't deign to compare S/N equipment with more elite brands, but as a solid, consumer-based brand, it holds its own. Still, as regards attenuation, I could be full of it; seems the more familiar I become with the medium, the more ignorant I find myself.

I reckon that's life, eh?


Properly sheilded cables shouldn't be putting out RF.
Cheap power strips can do this tho, and old EQ'S can make exelent
broadcast antennas also.
And dont get me wrong, Sherwood is an exelent brand, especially for those on a budget, but sheilding might be remiss in a cheaper receiver.
I got crosstalk in an Yamaha once, and it was 800 bucks:1:

Worf101
10-14-2008, 04:17 AM
Sometimes... I feel like a low grade moron round here... I'll have my morning cuppa and try again in an hour or so...:crazy:

Da "Vewy Confwused" Worfster

Rich-n-Texas
10-14-2008, 04:32 AM
I've never owned real high dollar equipment, but I also know that I've never had a problem with RF interference... at least I could never hear the effects of it. Do you have three prong AC outlets in your apt. Aa?

Auricauricle
10-14-2008, 06:43 AM
I have three-pronged outlets in the apartment. The same wall that has the outlet for the stereo also has an on-off switch for a ceiling fan that has been known fur humming a bit louder than it needs to occasionally, making me wonder if the receptacles are wired in parallel or interfere with each other some way.

Interesting comment about old EQ's; I'll look into that.

In either case, I just learned (yesterday) that the job I interviewed for a few weeks ago has panned out. Orientation begins this Monday. In short order, I will buy a power conditioner and see if that makes a dent. Thinking about Tice.

emesbee
10-14-2008, 09:58 PM
I'm afraid you lost me with that explanation, I won't even attempt to understand it.

My tweaking has been confined to bi-wiring my speakers, upgrading cables and interconnects, re-positioning speakers, all with positive results.

pixelthis
10-15-2008, 12:39 AM
I have three-pronged outlets in the apartment. The same wall that has the outlet for the stereo also has an on-off switch for a ceiling fan that has been known fur humming a bit louder than it needs to occasionally, making me wonder if the receptacles are wired in parallel or interfere with each other some way.

Interesting comment about old EQ's; I'll look into that.

In either case, I just learned (yesterday) that the job I interviewed for a few weeks ago has panned out. Orientation begins this Monday. In short order, I will buy a power conditioner and see if that makes a dent. Thinking about Tice.

I love this!!!
You obviously have been around the block on your trike quite a bit,
seem to have learned a tad here and there.
And after a post that woould confuse an engineer you post that the
outlet is shared with a ceiling fan
A CEILING FAN!!!!
Are you mad sir? You know what kind of motors those monuments to bad decor choices have?
MY GOD!!!
Its a wonder you can hear anything but a woop woop woop as
that sucker spins around.:1:

Hyfi
10-15-2008, 02:52 AM
The other thing that bothers are florescent lights. I have a few in my kitchen. My living room rig is on a dedicated circuit from the main box but I still notice some degradation in the sound when they are on. I also hear a nice "pop" when they get turned off and the sound level increases while the noise floor drops.

If you live in an apartment, everyone else's electronics and the place's poor wiring can be effecting you while your components themselves are just fine in an isolated environment.

Mr Peabody
10-15-2008, 05:29 AM
When looking at power conditioners you need to look closely at what they do. The products seem to vary widely from glorified power strips to full blown units that do everything from filtering to surge protection. I'd avoid those that claim to keep a constant voltage. I've read papers that claim this is virtually impossible to do and if it was possible it would cost a fortune. I don't think you have to worry about current limiting but that can be a concern when moving up to higher quality gear which will demand more current than a typical receiver. You mainly want to look for good filtering and isolation to address your issues. You might take a look at PS Audio products. www.amusicdirect.com was running a sale on PSA but I'm not sure how long it was going on. They have a 4 outlet version of my Quintessence. I had good results with this unit.

Auricauricle
10-15-2008, 06:20 AM
Those "monuments to bad decor" are absolutely essential if you live in this part of the country, Pix. B'sides, I never said that the wall outlet and the fan switch were connected; I said they MAY be.

I kinda like the "whoop, whoop"; you mean that's not my CD player? (Duhhh....)

Unfortunately, a dedicated circuit is an extravagance that will have to wait, alas, Bri. Alack.

Thanks for the tip on the conditioners, Mr. P. I will keep the filtering and isolation issues in mind as I search. BTW, I hear these things significantly (favorably) impact upon the noise floor. That's pretty sweet.....

Mr Peabody
10-15-2008, 07:04 AM
Power conditioners do help reduce the noise floor. Some people seem to notice it more than others, as well, some products work better than others which brings me to another suggestion, buy from some place that will allow returns in case you are not satisfied with the first one you try.

Ceiling fans, luckily the one in my listening room is silent. I think getting a good sturdy brand WITHOUT a light fixture helps with noise. I still rarely use it when listening to music, even though I can't hear it, it still some how is a distraction. I know a lot of people prefer listening in the dark but perhaps anything that disturbs a sense can have an effect on our concentration. Maybe not concentration, I can do more than one thing at a time but it's something about it.

Rich-n-Texas
10-15-2008, 07:38 AM
Those "monuments to bad decor" are absolutely essential if you live in this part of the country, Pix. B'sides, I never said that the wall outlet and the fan switch were connected; I said they MAY be.
He lives near Atlanta I think so he should know better. I've got ceiling fans all over my house and they don't distract me or my equipment in the slightest.

I was going to comment on the outlet location. It may be on the same circuit since they're both on the same wall. As a general rule I don't plug any A/V equipment into a switched outlet, and it doesn't sound like you did either.

pixelthis
10-15-2008, 10:36 PM
Those "monuments to bad decor" are absolutely essential if you live in this part of the country, Pix. B'sides, I never said that the wall outlet and the fan switch were connected; I said they MAY be.

I kinda like the "whoop, whoop"; you mean that's not my CD player? (Duhhh....)

Unfortunately, a dedicated circuit is an extravagance that will have to wait, alas, Bri. Alack.

Thanks for the tip on the conditioners, Mr. P. I will keep the filtering and isolation issues in mind as I search. BTW, I hear these things significantly (favorably) impact upon the noise floor. That's pretty sweet.....

A ceiling fan is nice where I LIVE ALSO( stirs the humidity around)
but from what you said the switch shares the same fixture as your
audio plug.
And if they are both in the same wall they do share wires, trust me.
Sheilding for electric motors has gotten quite good in recent years,
but why tempt fate?.
Get an extension cord and get your juice from somewhere else.
Please.:1: