Bass leaves after amp warms up?
It seems that you have spent a considerable amount of time trying to regain the good sound after it is lost but have you spent anytime trying to lose the good sound. IOW have you done the mute/unmute or switching inputs etc repeatedly before you have lost the good sound to try and create the problem? If you have some success on causing the problem on purpose it would give us another clue. |
It seems switching between sources or mute using the remote causes a break in the circut. When I release mute The fuller sound has been comprimised. Sounds less like an audiophile system I noticed sometimes while turning a record & putting needle down the same "distruption". This dosen't happen all the time but enough to make me aware of it. I always loose the good sound at some point After using remote for the amp odd concidence that's when the sound may change |
I didn't read all 250 posts. Did you try different speakers? Hopefully a different brand and one that has a warmer tonal balance. I still believe your system is going through its normal cycle, but where most people would say the sound improves your is going too far to the lean side. It doesn't take much in the way of warmth to make the bass sound dried out and make the music uninteresting. |
Ralph, Al, and Mr. Fishing..., just trying to be a detective, if this problem has occurred with other integrateds/amps, do we know if they use mosfets. If not, and all the amps pucker out with bass, what else is left to check. I've been harping about the PSB's low impedance specs affecting the MF and whether Zeros might help. The only practical way to check is for Mr. Fishing to borrow, if at all possible, another set of "normal" speakers and see what happens. If all is good, the culpret has been identified -- it's the PSB speakers. I highly recommend this reality check. If not, it's either the amp, notwithstanding that Mr. Fishing thinks its ok, then the cables, and if cables are ok, then lastly, he should rule out para-normal poltergiest activities. By any chance do we know if Mr. Fishing ever visited Amityville, CT (??). I understand that modern day ghosts are quite mobil. :>') BIF |
Does anyone know if all the amps in question are MOSFET outputs??Ralph, I took a look at the schematics for the Bryston B60R and B135 integrated amps, which are available at the Bryston site, and they both use bipolar transistors in their output stages. A post earlier in this thread by Mcintech, dated 4-16-13, indicates that the Musical Fidelity M6i does as well. I couldn't find anything on the web indicating otherwise. Best regards, -- Al |
Hi Atmasphere: I lost the bass yesterday after "looking" for it all day. I turned off the amp as you said and shortly after it was back. But there is no pattern yet..I'm working with this procedure right now.. Today I played a Record with full dynamics & everything sounds good. I am going out for the day and will listen when I return. I have noticed better response during the am than pm but again it's not really consistent. I'm working on acquring a SPL Meter probably from Radio Shack unless someone I know takes the time to visit me. I have a portable cd recorder & plan to record when the bass is there & not-maybe hear the difference from the cd I make. Thanks Tony |
Fish, Here is perhaps one of the least expensive amp options out there I have seen that has similar power to your integrated but also advertised ability to double down to 4 ohms. SOme good reviews out there on it, though I have not heard, but low cost might help make it a viable option to consider at some point. Do the SPL meter test first though in order to get a clearer handle on what is going in currently. Class D audio amp |
One more idea: your hearing might be exceptionally good. The PSB Synchrony models have an unusually low spike at the tweeter's resonant frequency, around 16-18 kHz (or maybe this is simply a spike in the treble apart from the resonant frequency). It's possible that (like me) you're still young enough that your hearing extends up this high and you're bothered by the spike, finding the sound fatiguing. From JA's review of the Synchrony One: "The top octaves sounded smooth to me on this Telarc SACD—the delicately brushed triangle at the end of the final variation before the fugue was beautifully resolved, without sounding spotlit—but Erick Lichte was less tolerant than I of the PSB's performance in this region. However, in the "Measurements" sidebar accompanying this review, I wonder if he was reacting instead to the small response peak between 16 and 18kHz, which, unlike me, he could hear." http://www.stereophile.com/content/psb-synchrony-one-loudspeaker-measurements This could create listening fatigue for you and possibly (my dead horse takes a further beating) trigger the acoustic reflex--further creating a perceived tipped-up tonal balance. |
Beating my own dead horse here, but I suggested it 200 or so postings ago and it could still be a piece of the puzzle. It goes with what Jjrenman said above about listening fatigue. This problem (especially if the OP's system sounds at all fatiguing) could be entirely explained by the acoustic reflex--the natural reflex our bodies have to surprising, loud, or unpleasant sounds that mechanically diminishes the conduction of sound to our inner ear. I'll quote from Tyll's "Loud Music Sucks" article on Innerfidelity: "Your listening system has built in protection from loud noise called the acoustic reflex (also called the stapedius reflex). When you are exposed to loud sounds, small muscles (stapedius and tensor tympani) in your middle ear tense to increase the mechanical impedance of the system of small bones (oscicles) that move vibrations from your eardrum to your inner ear. The net result is a reduction in amplitude of sound being transmitted into the inner ear of up to 20dB at low frequencies, with less attenuation as frequency rises up to about 2kHz where no attenuation is seen." Please note that he also hypothesizes that the acoustic reflex is why so many people describe show systems as bright--their bodies are mechanically filtering the bass out of the (too loud) sound. http://www.innerfidelity.com/content/loud-music-sucks 20 dB is a HUGE difference in the bass and having this happen would absolutely result in a perceived loss of bass impact but would NOT mean anything is wrong with your hearing. On the contrary, this would mean your body is responding as it should to loud sounds. Apart from measuring LF test tones, this is also where an SPL meter comes in handy. You say you listen at low volumes, but low for me is 50-60 dB with 80-85 dB my max. For others 80 dB might feel like a starting point. As I said before, I can feel and hear my own acoustic reflex kick in at volumes as low as 60 dB if I find the sound of the system (or natural sounds around me) unpleasant. If your SPL meter shows an objective reduction in bass output, I will gladly cheer on an appropriate resolution to your problem. However, if the SPL meter shows the bass is still there but you're not hearing it, the acoustic reflex is on the table. You have great equipment which I'm sure sounds very good, but certain components have been accused of brightness and in combination (at whatever volume) could be making you subconsciously cringe as this reflex kicks in. Again, Fishing716, I'm not saying it's all in your head or that there's anything wrong with your hearing--just that there is a possible explanation outside of swapping gear. And if it IS the acoustic reflex, you might start looking for gear that sounds less fatiguing. |
Fishing716 - A couple of suggestions. What I have found with some mosfet amps is they go through cycles. On turn on, very transparent, then after a while they go gluggy. However if you wait another hour then the transparency returns. The other suggestion would be to get the amplifer checked over - get the "bias" checked to make sure it is in spec. The bias will determine the operating temperature to some degree and too high a bias can result in "gluggy" sound. |
Atmasphere I tried your suggestion of turning off the amp when the sound changes and my first try was successful! I only waited 10 minutes and returned but the bass was back in full bloom. I don't know how long it will last but will explore this development till I discern a pattern. Something must be overheating? |
Just re read all of the Fishing716 posts to find a pattern. Please correct me if I am wrong but it seems that there is rarely a time that the bass sounds bad when first turning the system on for that day and also you have had marginal success by often fiddling with the cables. You also have mentioned that the bass leaves quickest with video sources. Another "grasping at straws" would be to dermine if something in your speakers are getting so warm that the "Q" of the speaker increases enough that the bass no longer has punch, impact or definition to it. You could try losely filling your ports with spongy foam before you turn on your system to see if you can recreate the "flat" bass sound for us. It does not hurt anything to try. Yet another "grasp" would be some kind of capacitance build up in your cables that can be dissipated with enough fooling with them, not that I know how that could happen. I know that these are some pretty out there ideas but it is all I could come up with as the other posters have done an excellent job of covering the subject. |
I set up just analog no digital but w/power conditioner. Once again I found the sold,dynamic sound. I said if this stays I will forgo TV,DVD even CD. But just 20 minutes into listening I could hear the kick drum less & less And over about 10 seconds my sound was gone. When the song was over I had entirely different presentation than previous. I went back to song #1 & it was crap In a word anemic sounding I just heard this song and it was powerful,clear,driving with punch..You name it the sound was the way I like it. Before I could sit back and enjoy,it was gone. I'm not making this stuff up.. |
I've been following this post from the beginning but do not remember if the following has been asked. Do you know anyone else that has a similar system that you could spend some time listening to? I'm wondering if the problem is tied to a form of listener fatigue. I do not mean to offend. I ask only because somedays I can listen for hours on end with no perception difference and on others it goes quicker. Especially if I have had to mix sound for a band the day before. The patterns of the sound quality coming and going do not overtly suggest this but I thought I would throw in on the "grasping at straws". |
Hmmm, this is probably grasping at straws, but your mention earlier in the thread that you live "close to Brooklyn" prompts me to ask if you happen to live near JFK airport. A member recently mentioned in another thread that in the past he had sonic issues in his system that were caused by radar that was in use at a nearby airport. The problem went away when he moved to a different city. Perhaps sensitivity to that or other kinds of interference will vary as a function of the warmup state of the equipment. Grasping at straws, as I say, but who knows? Regards, -- Al |
Perhaps another clue: Today it was suggested I play analog w/no digital I took out all the cables and set it up but had a disappointing sound. Took everything out tried again w/digital repluged in Again,Unable to regain optimal sound even with one speaker. Took everthing out again and reconnected just analog turntable. This time the bass returned w/full dynamics (one speaker) Question: Could the way wires are falling on each other or something else during set up be causing this mess? I will use this opportunity to listen G.Harrison Material world 180g vinyl Hope at least to get through one album before vanishing act. Thanks for everyone's patience with my illogical audio problem. |
If the digital was unplugged, seems like we can rule that out as being a problem. Go ahead and restore the system. I realize I made a poor assumption. I would not have turned off the amplifier when messing with speaker cables. Most transistor amps don't care, and our amps don't care, so I always leave them on. The fact that they are getting shut down is significant. As I mentioned earlier, the fact that messing with the cables gets a response is an important clue; turns out the amps were shut down during this time! They have become suspicious again. The only bugaboo is that I think we did a test where the system was played until the bass dried up, then it was turned off for a while and restarted. The bass was still gone. But maybe it was not shut off long enough. Next time the bass dries up, shut the entire stereo off for about an hour, then see how it sounds. |
But I think you will practically attain very high levels of performance sooner by using a dedicated amp better suited to bring out the best in the PSBs. Use the current MF integrated as a pre-amp only then, as AL suggested. I have requested loan of MF amp from my Dealer Still no response I have arranged person with SPL meter to visit next week. AP |
"I'm more than beginning to suspect a curious "malfunction" in my processes if not hearing/interpertation." Again, SPL meter would help establish if the effect is real/physical/measurable or not if in doubt. If it can be measured, then you know with confidence what you hear is for real and not an artifact of your hearing or how you listen. IF nothing measures, then two options: 1) try an amp that is clearly better for the job 2) track down Mr. Freud and see if he is available. :^) |
I disconnected all the digital & power conditioner. All I'm running is the turntable plugged into the wall. Today was probably the worst sound in a long time I seem to be going in the wrong direction I was unable to establish the solid bottem end at all. The sound was restrained & boreing/lack of dynamics. I switched speaker cables many times with no eureka moment. My conclusion is I am in someway inept at the task at hand and require an expert. I get deep bass sometimes which I enjoy and I get passive bass most other times. Perhaps the power conditioner is bumping up the bass sometimes like a subwoofer & then settles down to less dynamic sound? The other day I borrowed Analysis Silver speaker cables from the cable company and hooked them up. There was alot of indistinguishable "noise" in the bass region but it was undefined & I didn't like it at all. Perhaps the Audioquest comet has some way of "doubling" the bass in the first hr. Again I need someone with knowledge of what sounds right to assist me. The bass when it is there clearly is is taut yet supple,moves air & can eaisly follow the bass line..Adding much emotion & excitment.. I get that with all sources or not with any sources.. I'm more than beginning to suspect a curious "malfunction" in my processes if not hearing/interpertation. I don't even think Freud would take this case.. |
"Yes the optimal sound has left then returned an hour or day later but I usually fiddle the cables long before that happens." Its possible that if the amp is on but not playing music that it might return to a more normal state when played again. What would work against the amp can't handle the load theory is if the sound ever improves after the suckout occurs while the music is still playing and without changing anything, not after sitting idle for some period of time. |
Today I will set up just amp & turntable sans digital. Sounds like a great experiment. I would also use the power cord that came with the amp instead of the Kimber PK10 you have been using, and everything plugged to the wall outlet. Keeping the system as simple as possible will help to resolve the problem. |
Lowrider and Al, my sense is that a Bryston separate amp would muscle its way through any power delivery barriers (short of a short) -- if that's the problem. Btw, admittedly, my Paradigms are about 3 db more sensitive than the PSBs. Even still, it's been my experience that my ARC VS-115 has had no problem with power delivery. Indeed, SPLs are painful if I turn the gain up on my line stage more than 50 percent. Further, if you read some of my other posts in other OPs, you will see that I have neurotrically obsessed about my speaker's wacko impedance and phase angle numbers. At Al's and Ralph's recommendfation, after intense consultations with an audio-shrink, I am now convinced that somehow my poor little VS-115 (120 wpc) has deftly powered my "tube unfriendly" speakers very nicely. Al, I re-reviewed the impedance and phase angle graphs. The measurements from JA and SoundStage are quite different. BUT I think both bench measurements still raise the same issue -- can Fish ...'s integrated deliver power into those impedance numbers without getting indigestion?? So ... the bottom line is IF (???) Fish..'s integrated is having indigestion driving the PSBs because of the low impedance levels, the Zeros may effectively double what the amp sees. As alluded to above, even if the amp's power output is cut to 100 wpc, I think Fish...'s ears will hurt if he pushes the gain up. Incidentally, if Fish...'s amp is rated at 200 wpc at 8 ohms, presumably doubling the PSB's 4 ohm nominal impedance number should not significantly affect the amp's power delivery capability. So Mr. Fish...., as Al or Ralph said above, if every possible logical theory except for one illogical theory has been ruled out, then the remaining goofy theory must, no matter how improbable, be the answer. I suggest you call the Zero guy, tell him your problem and confirm if he'll take the Zerosm back if they don't work. Otherwise, go invest in a monster Bryston or get new speakers. IF you're really satisfied that everything else really is A-OK, then this is the only possible answer. IMHO of course. |
