Hello everyone,
Prepare for a wall of text.
TL;DR at the bottom.
Move this post to the proper area if this isn't it.
I'm currently modifying my Logitech Z-523 set to fit with my Apart speakers. My problem is that the sub of this particular set goes way too high, to around 1-1.5kHz. This in my opinion hinders the bass for not having enough control and has some weird echoing.
I've attached the pictures of the amp board and was wondering one of you could trace the circuit and tell me what components to change or remove to achieve a low pass filter around 70Hz. Why at 70Hz? Because the Apart speakers I have go to 70Hz without a problem but after that the sound is barely hearable unless you crank the volume up.
I got a little help from a friend of mine to get the high pass out of the way for the main speakers but he's busy atm with school so he can't help me as for now.
I've tried to draw the circuit but can't come up with anything that makes any sense.
http://img.tapatalk.com/d/14/09/04/7y5ynu4a.jpg[/IMG
[IMG]https://img.tapatalk.com/d/14/09/04/re9e3emu.jpg
Here's the link to my tracing(it's a psd file):
https://docs.google.com/file/d/0B-56TirPEjcVUkt4dnpJSnR3M0E/edit?usp=docslist_api
Here are the values of the resistors and capacitors around the op.amp. for the sub if they help at all:
Resistors:
R64 4k7
R57 15k
R56 15k
R29 97k7 (97k)
R63 10k
R28 46k
R29 9k04 (10k)
R26 9k04 (10k)
R24 972r (1k)
R23 21k51 (21k)
R22 8k97 (10k)
R25 27k22 (27k)
R27 16k34 (16k/17k)
R55 8k05 (8k1)
R67 5k41 (5k4)
Capacitors:
C25 2a103j
C28 2a224j
C29 2a224j
C30 2a683j
C31 2a104j
C63 471
C62 22
C50 104
C61 22
C66 102
Thanks!
TL;DR Sub goes too high, need help making an active low pass filter. Around this op.amp.
Prepare for a wall of text.
TL;DR at the bottom.
Move this post to the proper area if this isn't it.
I'm currently modifying my Logitech Z-523 set to fit with my Apart speakers. My problem is that the sub of this particular set goes way too high, to around 1-1.5kHz. This in my opinion hinders the bass for not having enough control and has some weird echoing.
I've attached the pictures of the amp board and was wondering one of you could trace the circuit and tell me what components to change or remove to achieve a low pass filter around 70Hz. Why at 70Hz? Because the Apart speakers I have go to 70Hz without a problem but after that the sound is barely hearable unless you crank the volume up.
I got a little help from a friend of mine to get the high pass out of the way for the main speakers but he's busy atm with school so he can't help me as for now.
I've tried to draw the circuit but can't come up with anything that makes any sense.
http://img.tapatalk.com/d/14/09/04/7y5ynu4a.jpg[/IMG
[IMG]https://img.tapatalk.com/d/14/09/04/re9e3emu.jpg
Here's the link to my tracing(it's a psd file):
https://docs.google.com/file/d/0B-56TirPEjcVUkt4dnpJSnR3M0E/edit?usp=docslist_api
Here are the values of the resistors and capacitors around the op.amp. for the sub if they help at all:
Resistors:
R64 4k7
R57 15k
R56 15k
R29 97k7 (97k)
R63 10k
R28 46k
R29 9k04 (10k)
R26 9k04 (10k)
R24 972r (1k)
R23 21k51 (21k)
R22 8k97 (10k)
R25 27k22 (27k)
R27 16k34 (16k/17k)
R55 8k05 (8k1)
R67 5k41 (5k4)
Capacitors:
C25 2a103j
C28 2a224j
C29 2a224j
C30 2a683j
C31 2a104j
C63 471
C62 22
C50 104
C61 22
C66 102
Thanks!
TL;DR Sub goes too high, need help making an active low pass filter. Around this op.amp.
First off:
1: What are the bracketed resistances for? The others look like E48/96 values which would make sense in a way.
2: why do you want to use this unit? (it MAY include driver specific response shaping as well as simple filtering)
3: schematic link needs reposting as a link.
4: the value of C required to drop sub crossover from 1k to 70hz will likely mean the capacitor wont fit on the board.
Removing the high pass is the easy part. I hope you have DC blocking....
1: What are the bracketed resistances for? The others look like E48/96 values which would make sense in a way.
2: why do you want to use this unit? (it MAY include driver specific response shaping as well as simple filtering)
3: schematic link needs reposting as a link.
4: the value of C required to drop sub crossover from 1k to 70hz will likely mean the capacitor wont fit on the board.
Removing the high pass is the easy part. I hope you have DC blocking....
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1. Nearest rounding to E12 for these are the ones I have access to.
2. Because I'd like to use what I currently have and because the mrs would kill me otherwise. I don't think there's any shaping involved, it's a semi-cheap 2.1.
3. Will do that when I get home today.
4. To me it looks like an active Sallen-Key filter, though I may be wrong. So depending if the online calculators are correct I can use two 15k resistors in series and one 220nF cap and one 110nF cap parallel to achieve this 70Hz low pass. Original caps are 100V, so I doubt the voltage in circuit even reaces 63V.
+1 schematic would help alot. I found a good online calculator, ill try and dig out the link if its any use.
Id say that 40-63v caps would be fine. 220n depending on type may be large. Saying that the mylar caps already there aren't small so i couldve been jumping the gun.
Judging by the two dual op amps ( cant read pns so guessing ) there is probably no shaping. But its possible that the curves are arbitrary and without running the values, its hard to know the exact filter curve.
Id say that 40-63v caps would be fine. 220n depending on type may be large. Saying that the mylar caps already there aren't small so i couldve been jumping the gun.
Judging by the two dual op amps ( cant read pns so guessing ) there is probably no shaping. But its possible that the curves are arbitrary and without running the values, its hard to know the exact filter curve.
Hi Guys ! You will save my audio system...
@Jekku0966 Could you please give the colors/value of R42 on the amplifier board? Mine burnt and i can t well on your picture.
Thanks a lot
@Jekku0966 Could you please give the colors/value of R42 on the amplifier board? Mine burnt and i can t well on your picture.
Thanks a lot
Hey......
did you managed to get your amp repaired. I have the same issue with the R42 get burning hot and then the system losing power/shutting off. R42 is 220ohm btw.
Ehi, I've got this thing (apart ) too 😛😱
The crazy thing is that the PSU is switching type, putting out around 16.5 V!
I did want to "tweak" the cable side, as it is 2m long and keeps the signal running along it. and +B
The volume/switch/bass box contains a headphone amp
Well, it's a box 'cos it contains the speakers 🙄
The crazy thing is that the PSU is switching type, putting out around 16.5 V!
I did want to "tweak" the cable side, as it is 2m long and keeps the signal running along it. and +B
The volume/switch/bass box contains a headphone amp
Well, it's a box 'cos it contains the speakers 🙄
That [substance] stabilizes mechanically the components, being the electronics in the subwoofer box
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