I have the same issue, I got a replacement amp plate that still has the noise, but a vit lower. Several folks are "suffering" by the same issue.
Repositioning the sub in the room, away from the ears, could hell a bit.
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My quest to eliminate the noise/rumble of my SVS SB-1000
- Thread starter MCH
- Start date
Repositioning the sub in the room, away from the ears, could hell a bit.
- Thread Starter
- #22
Hello guys, i have made some progress with my subs but i could do with some advice.
I went ahead and bought an Aiyima A07 max -the new version of the Aiyima A07 that has mono mode- and bypassed the plate amp of the SVS soldering the driver cables directly to the high level inputs of the sub. Then i can use the sub as if it was passive leaving the plate in place but unplugged:
Et voilà, the rumble is completely gone and, to my ears, it sounds fantastic! Easiest and most satisfying mod ever!
As i have two identical SVS SB1000, i took the chance to measure the modded one vs the stock one:
Regarding SPL, my UMIK reports that the stock sub can reach 105 dB at max vol (with REW pink noise) and with the Aiyima at max vol in exact same conditions it reaches 110 dB, so no issues there. Man, the little aiyima literally dances on top of the sub when maxed!
Now, of course, i am bypassing as well whatever DSP the SVS has built in. Reading the datasheet of the DSP chip i had the impression that there was nothing complex going on, probably only the volume control and low and high pass filter. But to check it out I measured some sweeps with REW and i can see some differences. I don't know how relevant (good or bad) these differences can be so i am posting the measurements seeking for advice.
Here is the full sweeps. There is no EQ at all, I just adjusted the volume of both the aiyima and the stock plate amp. I took two measurements of each just in case. Both subs were measured exactly in the same position with the mic also in the same position:
the SVS is set with the xover frequency at its max value, obviously the aiyima plays full range. Other than that, the only differences i see is the boost between 20-40 Hz in the SVS and a lower response between 45 and 90 Hz. Both filters have a strong influence in the distorsion:
SVS: the boost at 20-40 comes with a boost on distortion:
Aiyima: much less distortion at 20-40 but significantly more at 45-90:
finally phase. I dont know how to read this so i just leave it there. They look quite different. Comments are welcome.
SVS:
aiyima:
what do you think? there is no way i revert the mod and go back to the stupid rumble, but will i be missing something?
(of course, i will be applying proper low pass filter at 100 Hz - mains are kef LS50 meta - and room eq)
I went ahead and bought an Aiyima A07 max -the new version of the Aiyima A07 that has mono mode- and bypassed the plate amp of the SVS soldering the driver cables directly to the high level inputs of the sub. Then i can use the sub as if it was passive leaving the plate in place but unplugged:
Et voilà, the rumble is completely gone and, to my ears, it sounds fantastic! Easiest and most satisfying mod ever!
As i have two identical SVS SB1000, i took the chance to measure the modded one vs the stock one:
Regarding SPL, my UMIK reports that the stock sub can reach 105 dB at max vol (with REW pink noise) and with the Aiyima at max vol in exact same conditions it reaches 110 dB, so no issues there. Man, the little aiyima literally dances on top of the sub when maxed!
Now, of course, i am bypassing as well whatever DSP the SVS has built in. Reading the datasheet of the DSP chip i had the impression that there was nothing complex going on, probably only the volume control and low and high pass filter. But to check it out I measured some sweeps with REW and i can see some differences. I don't know how relevant (good or bad) these differences can be so i am posting the measurements seeking for advice.
Here is the full sweeps. There is no EQ at all, I just adjusted the volume of both the aiyima and the stock plate amp. I took two measurements of each just in case. Both subs were measured exactly in the same position with the mic also in the same position:
the SVS is set with the xover frequency at its max value, obviously the aiyima plays full range. Other than that, the only differences i see is the boost between 20-40 Hz in the SVS and a lower response between 45 and 90 Hz. Both filters have a strong influence in the distorsion:
SVS: the boost at 20-40 comes with a boost on distortion:
Aiyima: much less distortion at 20-40 but significantly more at 45-90:
finally phase. I dont know how to read this so i just leave it there. They look quite different. Comments are welcome.
SVS:
aiyima:
what do you think? there is no way i revert the mod and go back to the stupid rumble, but will i be missing something?
(of course, i will be applying proper low pass filter at 100 Hz - mains are kef LS50 meta - and room eq)
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- Thread Starter
- #24
Thanks, I will definitely leave the aiyima there, actually I plan to buy a second one for the other sub. Now I feel I have killer small subs!
I now wonder, as the minidsp & co. get popular, why don't they sell dumb subs with just one of these small amps inside?
I see a high pass filter done by the DSP at around 10 Hz, probably to protect speaker's diaphragm. Of course, it's easy to be seen the low-pass filter as well on the upper frequencies. If you can figure out a way to setup the crossover somehow it seems a great amp replacement.
BTW, did this amp swap solved any noise issues in the end?
BTW, did this amp swap solved any noise issues in the end?
- Thread Starter
- #26
Yes, normally I have my mains and subs with low and high pass filters and all is room EQed. I hear your comment about the high pass at 10Hz, sure, I can replicate that with EQ as well.
Yes! The noise is completely gone, and no pops when turning on/off the aiyima. The stock svs is good at that too, and this is important for me as I plan to have them switch on and off when a signal is detected like the stock svs do
With the audio interface you already own, it is pretty easy to make frequency response measurements of the SVS amplifier output using this technique -> https://www.diyaudio.com/community/threads/how-to-distortion-measurements-with-rew.338511/. Should be pretty easy to match once you have that measurement. You could also try at different levels to see if they were doing something weird from a dynamic EQ perspective but my guess is they just have some sort of limiter / compressor if anything.
Glad to hear the noise was resolved! Back when I was using a miniDSP OpenDRC-DA8 (unbalanced outputs), I had audible hum on my DIY subwoofers, so I understand your pain.
Michael
Glad to hear the noise was resolved! Back when I was using a miniDSP OpenDRC-DA8 (unbalanced outputs), I had audible hum on my DIY subwoofers, so I understand your pain.
Michael
- Thread Starter
- #28
Those are great ideas, never thought there could be dynamic EQ (I have my doubts though) or about measuring the amp response directly.
Not that I want to replicate the exact original response, I will be applying room EQ on top anyways, but now the amp is there doing nothing, why not?
What I don't have is a dummy load, but was thinking, if this amp is made to be used with this driver only, can I just use the driver as load? Or would it change the response the interface sees? (excuse my ignorance)
Second question, that I didn't see in the link (other than 1% or better). Any requirements for the resistors in the voltage divider? I understand there is close to no current flowing through them, but in case I am missing something.
Thanks for the suggestions, will post my results when I get them.
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