Shadorne - Ideally, balanced inputs reject all common-mode noise, but in reality they don't. They will reject some however. You will still get some ground-loop noise. The best scenario is using a signal transformer.
Steve N.
Empirical Audio
Digital Music sounds too bright?
If you feel your digital sound is too bright - I suggest you place a lightweight blanket over your tv screen or computer screen, if you have it placed between your main speakers. I did this and immediately heard a less edgy sound and improved separation between left and right channels. I have a 55 inch screen between my mains (Tyler Acoustics). This easy and free tweak made a noticeable improvement for me. Hope it will for you too.
(It makes complete sense that this will reduce some reflected sound. No one would ever recommend placing a mirror or window between main speakers, but a screen has the same effect. If you have a coffee table in front of you when listening, it also could reflect sound that undermines your speakers. Try covering it or moving it away).
(It makes complete sense that this will reduce some reflected sound. No one would ever recommend placing a mirror or window between main speakers, but a screen has the same effect. If you have a coffee table in front of you when listening, it also could reflect sound that undermines your speakers. Try covering it or moving it away).
56 responses Add your response
Shadorne - Eliminating ground-loops is a good idea. Few audiophiles do it. However, balanced alone does not get you galvanic isolation unless you have transformer coupling in the components. You can get it with this: http://www.empiricalaudio.com/products/final-drive Also, it is good to understand that most preamps and DACs, including my own, that generate balanced outputs using solid-state output stage are not really technically balanced because it is impossible for the + and - signals to be exactly the same amplitude, particularly over a wide range of signal amplitudes. The only way to get this is using a signal transformer. Once you do this, the amplifier tends to sound a lot better, so ther are more benefits to a transformer than just isolation. Jitter can usually be reduced more by using a reclocker, even though the DAC resamples and reclocks. knownothing - You may get to hear my Overdrive SX at future shows, but I'm not doing shows much anymore. It may be in another companies room. I am looking to do a headphone amp next, so I may just be in the headphone area at some shows now.
Empirical Audio |
Yes. One interesting thing about this particular discussion is that the changes I introduced in my digital front end that resulted in the described improvements to soundstage (and in basically every other attribute of sound) were done in effort to implement some of Steve's basic approaches in his excellent designs that I have have been reading about in other Agon threads and on the Overdrive website. Particularly focusing on improvements to power supply and management. Would definitely like to hear one of Steve's DACs at some point, and see photo of the defuser for TV screens described here. I very much appreciate Steve's input here and on this site in general. |
KN,I think you've nicely illustrated a number of things with your post, thanks for that. It seems that consistent with my suggestion, for a free mid fi upgrade, a simple blanket may help the soundstage. But consistent with Steve N. and others, this doesn't really address the cause, and there may be other approaches that are better and more complete [and cost money]. It sounds like you chose some upgrades, and once you got a good sound stage the blanket actually detracted (as I think Steve N. would predict). Hopefully I've not mis characterized anyone here - if so its not intended. I appreciate everyone's comments here. |
@audioengr +1 Ditto Since the measured performance of my DAC with Toslink is absolutely perfect and I have very few really high res files, I have opted for galvanic isolation rather than use the higher sample rate USB input of my DAC So I have complete galvanic isolation using Toslink to the DAC and balanced out to the power amp. Nice not to have to worry about the effects of cables and ground loops. However it needs a DAC with robust jitter rejection given Toslink is often the most jittery connection. For balanced I use Canare Star Quad cables. |
Like I said before, acoustic absorption between the speakers is not recommended. Only scattering devices, also called diffusers. Most speakers also need the reinforcement for bass from the backwall. I have a system that achieves pinpoint imaging with a 65" screen between and behind the speakers. I can get this because of the 1/4 round tube-traps next to the screen, the ultra-low jitter of my sources and the fact that I have zero ground-loops in my system. No component is grounded to any other component, except through the AC power outlets. Steve N. Empirical Audio |
Ok, so I noticed with a mid fi HT/2 channel system that putting a blanket over a 55" flat screen noticeably improved 2 channel soundstage for both analog and digital front ends in purpose built room. Soundstage with analog front end clearly better than internal DACs for Arcam receiver. Add an external DAC, soundstage improved sans blanket. Add external linear power supply? Better. Add good power cable for LPS? Better. With all these improvements in digital front end, blanket still helped. Add solid core quality copper speaker cables (21’), soundstage for digital and analog front ends now detailed and continuous side to side. BLANKET ON TV NOW DECREASES SOUNDSTAGE DETAIL. My experience tends to support many of the points made here, yet is hard for me to grasp what exactly is going on. Better imaging from speakers interacts differently with surface between them, and improving direct output crosses some point where blanket actually hinders presentation? Maybe try different coverings (default was thick fleece throw). Can see rabbit hole from here. kn |
Obviously the scattered background CD laser light is getting into the photodetector and producing errors. Which is why the Green Pen works, by absorbing red light as it spreads out from around the outer edge of the CD. Green, or more specifically turquoise or cyan, absorbs red light because it’s the complementary color for red. Now here’s where it gets tricky. The CD laser wavelength is actually around 780 nanometers nm which is in the near infrared spectrum of light, I.e., invisible light. There is some red in the laser light because the wavelength is close to visible red on the spectrum and because there is some discrete bandwidth to the laser light, it’s not monochromatic. Therefore one can reasonably conclude that the bandwidth of the laser extends above visible red )which stops around 700 nm) up to around 850 nm. Thus the Green pen only affects the visible red part of the spectrum below 700 nm. The rest of the laser light above 700 nm can not (rpt not) be affected by color. I.e., there is no complement for infrared (invisible) light. So, we have the situation where quite a lot of scattered laser light is getting into the photodetector EVEN IF MUCH OF IT IS ABSORBED BY THE GREEN OR TURQUOISE COLOR around the outer edge. |
@audioengr +1 "BTW, brightness is not usually due to acoustics. Its usually something else. Most people go down the garden path using cables that act as filter, ferrite beads or blankets to snuff-out the HF sounds. This is the wrong path to take. Figure out what components are really at fault. Usually excessive jitter from the source, whether computer or CD player, or poor preamp that adds too much distortion and has poor power delivery or even sometimes a bad DAC. This is typical." Yup. I would always address what components are really at fault FIRST before using cables to filter the poor sound. In fact, if special cables are necessary it may indicate a component is at fault or two components are incompatible with each other. |
Gutwire NotePad 2 Placed on top of transports and power supplies. http://gutwire.com/index.php?page_id=271 |
An alternative for damping spinning CD, SACD etc. vibrations is Herbie's Audio Lab's "Super Black Hole CD Mat". It is $ 32.49. The top of the mat is composed of carbon fiber for structural rigidity while the underside that attaches to your disc is made of a soft silicone that adheres the damper to your discs without an adhesive. You can use this forever as you can remove it from one disc and stick it onto the next thus realizing its benefits of steadying the spinning disc as it's digital information is read by the laser. |
The biggest problems with MOST digital are: 1) jitter from the source 2) poor digital filter in the D/A 3) format These can all be overcome with the right choices, equipment and treatments. Once you lick these and have a good DAC, it will beat 99% of the best vinyl out there. Vinyl is just not capable of the dynamics of digital, or the extension high and low. If you MUST play CD's (I don't anymore), then at least treat the read surface with something like Ultrabit Platinum plus, unless of course you have a transport that uses a memory buffer for playback. Also, it is even more important if you stop the vibration during playback by gluing a damper to the top of the CD or spraying a rubberized coating. These coatings have a significant effect on jitter. IF you have a platter-type CD transport, its not needed obviously. Steve N. Empirical Audio |
Right off I myself have always noticed is that placing anything your speakers will most certainly affect the audio reproduction. When I tried placing my tv on a steroeo cabinet right between my speakers the imaging between the speakers would be pretty much distroyed plus, of ourse the audio reproduction itself is greatly hampered. That is why I alway cringe whn I see either an individual, in an advertisement in a magazine, or even worse being demonstrating at an audio where all the audio electronics sit right between the speakers. That is why I always have my tv well behind the speakers them self. Possibly covering the tv with a blanket acts somehow like an audio tweak product to lessen the brightness effect caused by the tv. As an experiment, have someone stand directly between your speakers an notice how it will effect the sound reproduction. The bigger the person, or the larger the objects between the speakers, the greater the effect. I know. I wish I could bring my tv, which sits on a light wood table right up near me. A 50 inch tv looks much better up close verses 12-14 feet away, but unless I am using my headphones, it just does not work. |
@kalali, not really directly. That audible improvement you hear may be due to more of a difference in the geometry-vs-length-vs-gauge-vs-power load of the new power cord and also, presumably, the better (you could also say "lower noise") quality parts/better, or ’beefier’ power supply circuit design. But, the kind of noise I’m referring to above would be present in your setup either way. That source of noise is ’baked in’ to every system (even battery powered or "lab grade" power supplied) and it’s a different matter to "shield" wiring than it is (using the AMD method as I have) to reduce, block or eliminate electrical noise both before and after it has had a chance to impact the AV system - that is to say just that (given enough application of treatment) it’s a profound difference in the resulting sonic effects between the two...and how it translates into musical terms. I think that may be the hardest thing for audiophiles to wrap their minds around. Without the actual listening experience to enlighten you, then the natural assumption is that it cannot be that big of an issue, since everyone else’s experience is the same. I’m now one of those people that say that reducing electrical noise wholesale, if you can come across a good method to do that, leads directly to massive improvements across the board in the listening experience. This about the only true "night-and-day" difference in this hobby I’ve yet run across...which is why I sound like a broken record whenever I bring it up, which is relentlessly. @geoffkait , yes I agree, a great many reasons. Did not mean to say that AMD is a panacea or that it obviates the need for other tweaking at all. Although you do mention "...magnetic field interference, from transformers especially but also any wire that carries current, interconnects and/or speaker cables in reverse direction...". Actually I’m using AMD devices that are designed to specifically address these issues. One of them is designed to sit on top of a stack of gear (near the topmost transformer, although the exact spot is tuned by ear for the best sounding bass response) and it treats all the transformers in the stack - reducing their magnetic field and therefore the multiple field interactions - in my system, an extraordinary amount of improvement in the ebb and flow of the harmonic signature...a marvelously musical effect. |
There are a great many reasons why digital needs a lot of help. The reasons are not limited to RFI/EMI, "quantum noise," or Gaussian noise. Other reasons include but are not limited to seismic and internally produced vibration such as transformer buzzing, magnetic field interference, from transformers especially but also any wire that carries current, interconnects and/or speaker cables in reverse direction, system/CD out of polarity, CDs aggressively compressed, background scattered CD laser light interfering with the primary signal, out of round condition of many CDs makes them wobble, and CD transport vibration. |
Ivan_nosnibor "But I would say the main conclusion from my experiences so far is that the notion that digital itself is somehow Inherently inferior sound quality-wise is actually a complete myth. It just needs some serious help." Hmmmm, sounds like you actually agree with me. I never said digital couldn’t be improved. Thus the inherently inferior sound quality of untreated digital is pretty much as I described. Cheers |
It IS, OTOH, very common to experience this level of pervasive "digititis" or "harshness" with all digital. Truth is, you could redesign digital circuits ’til doomsday and never do anything in this particular regard but make yourself poorer. As I’ve said at Agon before, the real problem is where most people would not think to look - noise - electrical noise, that is. EMI/RFI and quantum or shot noise. Digital is more affected by this than the rest because of a double whammy - it happens to be more susceptible to the very kinds of noise it radiates. And it radiates more than most other gear. Again, there’s really no circuitry redesign or magic bullet that will resolve it...make some inroads here or there maybe, but not ever cure the problem. Quantum or shot noise is particularly problematic. All electrical voltage vibrates...the more the voltage the more the physical vibration - whether the circuit or component is loose or whether it is tightened down. Ever hear that one, particular power pole transformer humming from like a hundred feet away?? They all vibrate like that under voltage. They don’t all hum that noticeably because power crews are responsible for the periodic maintenance of tightening them back down as the vibration over time will loosen the (captive) mounting bolts. But, even the tiniest, weakest voltage in a circuit will vibrate at the quantum level - just not at an amount strong enough for us to detect, even by direct touch. That vibration is the radiation of electrical noise - both through the wiring (upstream and down) and through the air in all directions. We can hear it as hum and we can feel it as heat - EMI. The odd thing about this noise is that, assuming that you have a physical device to reduce or eliminate it, that one you’ve done so, quantum noise (because of its nature) will immediately begin to regenerate as you move anywhere downstream (or up) in the circuit. It regenerates and it does so in in rather random and unpredictable ways. There are devices that will work to kill quantum noise. AFAIK, Jack Bybee was the first to introduce the idea to audiophile world a while back now. But, the random regeneration of noise meant that his devices would, ideally, have to be located at as many strategic locations throughout the AV system as possible in order to achieve maximum effect. However, many people who have tried Bybee devices have had very positive things to say. I came across a different company in 2010 called Alan Maher Designs. Mr. Maher used the same basic idea, but found new ways to expand the noise coverage over a much larger portion of the noise spectrum which increased the AV performance and was doing so at lower costs. I have already raved about my own experiences with this company in other threads here. I started slowly with AMD products at around $25. That began to open my eyes and ears to the possibility of electrical noise reduction, so I continued on with it...up to and including the present - to the tune now of a bit over $10k, after well more than 50 different purchases from them. That’s probably the only way I could’ve ever afforded such a hifi-oriented expense - one financial step (and one evaluation) at a time. I can’t just write a check for 10 large ones to anybody. His devices, for the same reason as above, must also be distributed at various, but key, points throughout the system and even the home. There is no real shortcut for that (although Mr. Maher says he is working on a single-box solution that is still 5-6 years away that will treat an entire home). But, AMD transformed my system, without sonic fault of any kind, not only from the standpoint of digital noise, but with noise from all my components...and noise from my home. So I’m finding that all of the usual myriad sorts of audiophile problems that everyone else constantly deals with on an ongoing basis are now in the rear-view mirror for me. But, I would say that my main conclusion from my experiences so far is that the notion that digital itself is somehow Inherently inferior sound quality-wise is actually a complete myth. It just needs some serious help. Regards, John |
Nothing even remotely like that here. Full, entirely fleshed out, lots of inner warmth, smoothness with detail, flat response, clean, clear, extended, organic, full of life, airy, not a single too-bright CD in the house (a complete audio myth IME, BTW), excellent hi’s, mids and lows, palpable, real, natural, tonal and in-the-room presence, 3D, dynamic, harmonic ebb and flow, relaxed, involving, musical and with a distinct lack of the usual feeling of listening to a "recording". I’m listening to the living, breathing musical performance every single time out - right in front of me, regardless of CD format, disc, track, passage, genre, material, volume or time of day. |
There are many potential reasons for a bright sound, and a very common one is a screen placed between main speakers. Although it may not be the best long term solution, a simple test is to place a blanket over the screen to damp down the reflective surface. If this improves the sound, then you can consider members’ suggestions for better ways to eliminate or avoid reflected sound. If the test does not improve the sound, then you can consider all the other approaches proposed by the forum members. |
| Post removed |
I’m with audioengr on this. I’ve had both Thiel & Maggie 3.5’s with a big ugly TV right between ’em in a tight-ish set up and I never found soundstage or imaging suffering for it. In fact, that roundup could have been very bright, but it wasn’t. I got nothing but 3D magic out of that big, mostly Audio Research tube rig. There we’re curtains & rugs and a little bachelor laundry laying about to absorb sound. And a nice, twentieth century tube DAC does wonders. |
@erik_squires I bet if you marketed an audiophile TV cover, made from artisanal Chilean wool and sewn into a special geometry based on quantum photon entanglement, they'd listen. But a blanket over the TV? That's far too easy just to test and, by God, it's a blanket, not a specially designed and manufactured audio product! |
Randy, Try stand-alone panels next to the TV, parallel to your side walls, like this one: http://www.gikacoustics.com/product/freestand-acoustic-panel-gobo/ Best, E |
BTW, brightness is not usually due to acoustics. Its usually something else. Most people go down the garden path using cables that act as filter, ferrite beads or blankets to snuff-out the HF sounds. This is the wrong path to take. Figure out what components are really at fault. Usually excessive jitter from the source, whether computer or CD player, or poor preamp that adds too much distortion and has poor power delivery or even sometimes a bad DAC. This is typical. Steve N. Empirical Audio |
The blanket is not great. Absorbing things between the speakers is not a good thing. Better to have scattering. Instead, I use two 1/4 round tube traps from ASC in Oregon. I locate these next to the screen with the rounds pointing inwards. The screen simply dissappears acoustically because the backwave from the speakers is scattered. I've been doing this at shows too , even when there is no screen, locating them behind and inside the speaker lines. Improves imaging. Another critical thing is to have absorbers, like acoustic foam, on the side walls to absorb the secondary HF reflection. Put a mirror on the wall and if you see the tweeter from the listening position, you need foam where the mirror is. Steve N. Empirical Audio |
