Dziwny dźwięk z subwoofera SVS SB 3000

[MobyDick]

REL z zasady nie stosuje wejść RCA dla kanałów L i R  osobnych. Często jedno takie gniazdo jest filtrowane filtrem dolnoprzepustowym o regulowanej częstotliwości  a drugie LFE ma ustawioną  taką częstotliwość na stałe, do filtrowania niżej w wzmacniaczu do którego jest podłączony. Mostkowanie wejść kanałów L i R jest faktem. Jednak ze względu na obecność zakłóceń które dostają się poprzez kabel, który jest zwykle długi, lepiej aby był w nim podawany możliwie wysoki poziom sygnału, który powinien być obniżony do potrzeb w samym subwooferze. Z tego względu lepiej nie używać kabli Y gdy nie są konieczne, a konieczne są na ogół we wzmacniaczach samochodowych do zmostkowania dwóch końcówek mocy w celu uzyskania większej mocy na subwoofer.

[R_NEO]

Właśnie eksperymentuję z kablami i subwoofer na  Y gra nie tylko głośniej ale bas jest pełniejszy i nie jest taki kartonowy i w ogóle jest lepszy ale i tak nie jest to bas jakościowo którego bym oczekiwał z suba, który jest jak dobrze oceniany.

Edytowano 19 lutego 2022 przez R_NEO

[Jasiek88]

Wydaje ci się, głośność burzy ci odbiór.

[Kubakk]

U mnie głośność suba na 1 kablu LFE -10dB , na podwójnych do wzmaka -40dB , gdzieś czytałem ,że przy podwójnych kablach idzie większy sygnał

[Jasiek88]

1. Y-connectors:

People frequently ask about how to use Y-connectors with their subwoofers. RCA Y-connectors can be used for two different purposes. One purpose would be to connect two subwoofers into a single subwoofer output in the AVR. In that case, a Y-connector with two female ends and one male end would be required. A standard subwoofer cable has two male ends. One end plugs into the subwoofer input on the back of the subwoofer, and the other end plugs into the AVR subwoofer output on the back of the AVR. This is an example of a standard subwoofer cable:

Amazon.com: SVS SoundPath RCA Subwoofer/Audio Cable: Home Audio & Theater

Where two subwoofers need to be connected to a single sub out on the back of an AVR, a Y-connector with two female ends and one male end should be used. The subwoofer cables from the two subs would plug into the female ends of the Y-connector, and the male end of the Y-connector would plug into the subwoofer output on the back of the AVR. This is an example of that type of Y-connector:

https://www.amazon.com/AmazonBasics-2-Male-1-Female-RCA-Y-Adapter/dp/B01D5H8RE0/ref=sr_1_15?ie=UTF8&qid=1518124464&sr=8-15&keywords=y-connector+audio+signal+splitter+cable&th=1

A second and different purpose for a Y-connector would be to help a subwoofer power-on more easily from Auto mode, or give better level-matching results during the calibration process. Those scenarios, typically involving Yamaha or Onkyo AVR's, are explained in some detail at the end of Section II-E. In this application, a Y-connector with two male ends would plug into dual subwoofer inputs on the subwoofer, and the single female end would plug into a standard subwoofer cable. The standard cable would then plug into the subwoofer output on the back of the AVR.

Doing this would double the voltage going to the subwoofer amplifier, which would help it to turn on more easily, or in some cases, enable it to use all of the available power of the subwoofer amplifier. It would not however, increase the inherent output of the subwoofer. That inherent output is determined by the subwoofer amplifier. This is an example of that type of Y-connector:

https://www.amazon.com/AmazonBasics-2-Male-1-Female-RCA-Y-Adapter/dp/B01D5H8SGC/ref=sr_1_15?ie=UTF8&qid=1518124464&sr=8-15&keywords=y-connector+audio+signal+splitter+cable&th=1

 

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* People with some Yamaha AVR's are apparently much more likely to experience issues with subwoofers not turning on automatically unless AVR sub trim levels are relatively high--perhaps even fairly close to 0.0. That is due to the lower voltage signal sent from some Yamaha AVR's to the subwoofer. In some cases, this may have been due to some defective sub outs on some Yamaha AVR's, which were replaceable under the Yamaha warranty. Yamaha AVR's from about 2017 on were previously reported to have addressed the problem, but that doesn't seem to always be the case. Both Yamaha and Onkyo AVR's may also experience a calibration (level-matching) problem due to low voltage signals to the subwoofers. That issue is addressed in the last few paragraphs of this section.

If subwoofers will not turn on automatically in Auto mode, without higher AVR trim levels, then the higher trim levels may be slightly less likely to lead to clipping issues, since the voltage from the AVR was lower to start with. Some Yamaha owners use a Y-connector into both subwoofer inputs in order to double the voltage going to the sub. And, that typically resolves the Auto On issue. Of course, Yamaha owners can also choose to just leave their subs on all the time, if the Auto On issue proves to be a real problem. That will consume slightly more energy, but will not affect the operation or longevity of the subwoofer.

AVS member @Basshead recently mentioned a clever solution for achieving more headroom, with higher gains and lower trim levels, which seems to circumvent the Auto On problem with Yamaha AVR's. He went from a -1.5 subwoofer trim level to a -4.5 trim level, with a comparable gain boost, and obtained +3dB more headroom, prior to clipping. But, his subwoofer didn't power-on reliably when watching TV at very low master volume levels. So, he lowered the trim levels on all of his other channels by -3dB, and raised his MV level by +3dB, and is now able to have his sub power-on reliably for low-volume TV content, while still having more headroom available for louder movie viewing. This is an additional technique that Yamaha owners might wish to try.

One final issue involves Yamaha AVR's which yield abnormally high trim levels no matter how high the subwoofer gain levels are turned-up. This can be a much more significant problem than the auto-on issue. In a recent example from early October of 2021, a new Yamaha RX-A8A exhibited this issue of setting abnormally high trim levels with the subwoofer gains also set high. Some before-and-after screen shots of trim levels, showing the problem being solved with Y-connectors, are illustrated on Page 218 of the Guide thread. If you believe that your Yamaha (or Onkyo) AVR may be exhibiting similar behavior, it could be worthwhile to look at the pictures on Page 218.

Apparently, this can also be an issue with Onkyo AVR's. The typical voltage sent from AVR's to subwoofers is about 2.0V or slightly higher. I'm not sure what the voltage coming from some Yamaha AVR's is, but I have been informed by AVS member @fattire that with some Onkyo's it is only 0.9V. If the subwoofer receives substantially less voltage than the typical 2.0V, then its performance may be adversely affected, and that limitation may show-up during calibration. The subwoofer trim levels may be set too high even with very high subwoofer gain levels. That can be an indication that the subwoofer is not able to reach its normal output potential.

Where this problem is believed to be occurring, the way to correct it is to use a Y-connector into both sub inputs. That will double the voltage going from the AVR to the subwoofer. So, using Y-connectors can allow subwoofers to turn on automatically in some cases, and they can also be used to allow the subwoofer to achieve its full operating performance. Once again though, the Y-connectors are only effective where the voltage coming from the AVR is insufficient. They won't improve on the inherent performance capabilities of the subwoofer. Its own amplifier will determine the subwoofer's inherent capability.

 

https://www.avsforum.com/threads/guide-to-subwoofer-calibration-and-bass-preferences.2958528/#IA

Edytowano 19 lutego 2022 przez Jasiek88

[R_NEO]

Jeszcze jedna ciekawostka. Jak w aplikacji zmienię polaryzacja na negative to bas staje się przyjemniejszy i nie taki buczący ale nie wiem czy tak może to grać. Kable głośnikowe na 100% podłączone są do kolumn poprawnie ale jak je zamieniam i podłączam odwrotnie to i tak nie słyszę żadnej różnicy w dźwieku nawet jak zamienię je w jednej kolumnie.

[MobyDick]

Jeśli masz amplituner kd z automatyczną kalibracją mikrofonem, to powinieneś jej użyć. Ona powinna ustawić właściwą fazę subwoofera. Bez tego nie ma co mówić o dobrym jego funkcjonowaniu. To zależy nie tylko od kabli, ale głównie od elektroniki subwoofera i akustyki pomieszczenia, oraz jego połażenia względem kolumn i osoby która siedzi w miejscu odsłuchu. Przy innym sobwooferze taką kalibrację należy przeprowadzić ponownie lub przynajmniej na słuch ustawić fazę dla uzyskania najlepszego efektu.

[R_NEO]

Nie, na razie mam jeszcze stary amplituner. Zmiana polaryzacji to jednak złudzenie lepszego grania po prostu odcina jakąś częstotliwość i wydaje się że jest lepiej, bas robi się trochę mocniejszy ale odcina np. trochę dźwięk z kontrabasu ale buczący dzwiek wtedy zanika. Niektóre utwory brzmią na odwróconej nawet fajnie bas jest taki potężniejszy. Zmiana fazy nie zmienia kompletnie nic w brzmieniu.Nie długo chcę kupić albo Yamaha R-N803d albo NAD C700 ale musze najpierw posłuchać i w tedy albo go zostawię albo zamienię na inny.

Edytowano 19 lutego 2022 przez R_NEO