An externally hosted image should be here but it was not working when we last tested it.
saw this on taobao. very impressive
Then it appears to be components used that cause sound difference between your two boards...or...just noticed something, are the traces in output from chip to inductors tinned or just painted? If tinned, check both red caps crossing those tracks, could be a short then, caplead touching track going underneath it? Longshot...
Increasing inputcap value gives more bass, to get same bass from 20dB setting. But muting once will be easier then soldering smd LOL 3 big elco's are easiest to replace, and also can change dull to even overly bright.
edit metallic paint/liner can also be (somewhat) conductive
Increasing inputcap value gives more bass, to get same bass from 20dB setting. But muting once will be easier then soldering smd LOL 3 big elco's are easiest to replace, and also can change dull to even overly bright.
edit metallic paint/liner can also be (somewhat) conductive
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Is this from this site? I'm trying to figure out the best possible PS to power 2 boards am wondering what the user thinks of this and what it is?
An externally hosted image should be here but it was not working when we last tested it.
alright, modding a third danzz designed YJ blue board here.
Changed gain to 32db with 39k ohm resistor in place of 20k ohm.
Replaced power caps with Ti data sheet spec 220uF Panasonic FM 35v caps
Replaced input caps with WIMA MKS4 4.7uF (big ones) and WIMA MKS2 4.7uF (little ones)
Didn't change out the coils on this one so I can compare it to my other board.
Also made a power reserve cap bank with 8 nichicon HD(M) 1000uF 35v caps, but ran out of room in my box so cannot use that yet.
We'll see how this one does with the added value on the inputs.
Definitely getting faster with the iron now...
pics to follow.
Changed gain to 32db with 39k ohm resistor in place of 20k ohm.
Replaced power caps with Ti data sheet spec 220uF Panasonic FM 35v caps
Replaced input caps with WIMA MKS4 4.7uF (big ones) and WIMA MKS2 4.7uF (little ones)
Didn't change out the coils on this one so I can compare it to my other board.
Also made a power reserve cap bank with 8 nichicon HD(M) 1000uF 35v caps, but ran out of room in my box so cannot use that yet.
We'll see how this one does with the added value on the inputs.
Definitely getting faster with the iron now...
pics to follow.
With a 1uF input coupling cap the -3dB points will be as follows for each gain setting:
20dB 2.65Hz
26dB 5.31Hz
32dB 10.61Hz
36dB 17.68Hz
It's commonly accepted that bass will be effected negatively one order of magnitude above the -3dB frequency. On this basis, I'd usually go for the following minimum input coupling capacitor values to keep the -3dB points at 2Hz:
20dB 1.33uF
26dB 2.65uF
32dB 5.31uF
36dB 8.84uF
To anyone experiencing poor bass, this would be the first place I'd look (and remember to adjust for any output capacitance at your source - either bypass that or scale up the amp input capacitor to ensure the two caps in series meet or esceed the target uF for the amp gain level)
20dB 2.65Hz
26dB 5.31Hz
32dB 10.61Hz
36dB 17.68Hz
It's commonly accepted that bass will be effected negatively one order of magnitude above the -3dB frequency. On this basis, I'd usually go for the following minimum input coupling capacitor values to keep the -3dB points at 2Hz:
20dB 1.33uF
26dB 2.65uF
32dB 5.31uF
36dB 8.84uF
To anyone experiencing poor bass, this would be the first place I'd look (and remember to adjust for any output capacitance at your source - either bypass that or scale up the amp input capacitor to ensure the two caps in series meet or esceed the target uF for the amp gain level)
Thank you! So by putting a switch between the SD and mute pin, one could mute the amp at anytime.
Regards,
In reality, the the LF content in most tunes do not get that low. In fact, most of the speakers could not even achieve -3 dB at 20 Hz. That's really good spec for a speaker and one has to pay big bucks for it. As such, our speakers becomes the limiting factor, not the amp in terms of the ability playing LF.
My 2 cents.
Regards,
Like Sharpie31 said, the frequency loss below 100hz, could be heard in many speakers, -3dB at 20hz means losing output slowly from ~200hz (maybe a little higher) down. Like I posted earlier I noticed on my speakers and others did too. Maybe indeed if output of source befor amp is cap coupled with value high enough you wont notice, I dont know, I just notice bass drop at very normal speakers. With sure3110 this was more extreme because inputcaps there standard are 0.22uF.
I agree that in most real world scenarios the speakers and room will be the biggest limitation on LF performance. My attitude is that it isn't difficult (or expensive) to achieve good performance down to 20Hz upstream of your speakers, so I'll aim to do this. We audiofools spend large amounts of money pursuing less significant improvements in other areas. This ensures that the component doesn't become a limiting factor if the loudspeakers and/or room are upgraded in the future. It's also worth noting that deeper bass can be easier to achieve with headphones than loudspeakers, so working within the limitations of normal loudspeakers can easily compromise headphone performance. My headphones are about 5dB down at 10Hz.......
I just modded a board last night and it is the first one where I altered the values of the input caps to more closely match the data sheet vis a vis the altered gain.
So, with a YJ blue board I upped gain to 32db and installed 4.7uF input caps.
--I couldn't find any WIMA caps in 22mm/5mm pitch with the required 5.6uF values and 4.7 was the highest I could find.
Anecdotally, with Dayton b652 speakers, the low end does seem better/fatter/fuller.
But I just started listening at higher volume levels 10 minutes ago and therefore the board isn't burned in or anything.
So, with a YJ blue board I upped gain to 32db and installed 4.7uF input caps.
--I couldn't find any WIMA caps in 22mm/5mm pitch with the required 5.6uF values and 4.7 was the highest I could find.
Anecdotally, with Dayton b652 speakers, the low end does seem better/fatter/fuller.
But I just started listening at higher volume levels 10 minutes ago and therefore the board isn't burned in or anything.