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Deleted member 148505
You're welcome.
I'm using these elna silmic ii caps. About the sound, I prefer the nichicon muse, but the silmic might need some breaking-in, also it was recently heated by soldering few minutes ago.
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Deleted member 148505
Hello
I use this same smps from the start, works very well at (40V), it barely heats, 4 to 5 ° C above ambient temperature, ditto for the chokes, 8 for the TPA radiator (domestic use).
I switch to a Connex power supply this afternoon 48V (will be set to minimum), the auxiliary voltage will be used for the potentiometer motor.
Best regards
Roger
I use this same smps from the start, works very well at (40V), it barely heats, 4 to 5 ° C above ambient temperature, ditto for the chokes, 8 for the TPA radiator (domestic use).
I switch to a Connex power supply this afternoon 48V (will be set to minimum), the auxiliary voltage will be used for the potentiometer motor.
Best regards
Roger
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Deleted member 148505
Yes correct it doesn't heat up at all! Switching frequency is 65kHz, I will check if it produces clean noise floor.
My cheap chinese adjustable smps has a bump on the noise floor (when I checked THD+N of my amp) at around 25kHz. The abletec doesn't have that bump so I know that the smps is the culprit.
I'm using the meanwell LRS-350-36 at 41V DC. VER2923-103KL is only 4.6 deg C above ambient. The heatsink is 9.5 deg C above ambient.
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Deleted member 148505
I suggest that you change only the 4 input caps near the heatsink as the first step.
This elna silmic ii 10uF caps reduced the ultra low bass from the sound. Also it is very clean sounding. You might like the 22uF nichicon muse more..
Lester, ELNA SILMIC II (brown series RFS) is polarised, it is suited for power supply decoupling, not for signal path DC blocking.
It needs minimum 80 hours of break-in time, and then sounds very nice - when used in analog PSU path. Try it as decoupling cap for 3255's AVDD pin, and/or as supply cap for opamps. Not in signal path.
Edit: Actually you have 10uF value of RFS, which is ideal as bypass cap on your Opamp SMD adapter, between pin 4 and 8 of opamp.
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Deleted member 148505
I will check first if LRS-350-36 will not add any spurious frequencies in the noise floor. If the result is good then I will add softstart + additional bulk caps to reduce the ripple and noise.
If the result is bad i'll just buy the SMPS300RS 36V
About the input caps, the Nichicon Muse BP adds some noticeable distortion to the sound, I already verified it on my myref rev C, which has an input cap bypass jumper. Without the caps, the difference is night and day haha.
Maybe my ears got accustomed to the distortion. I will try to break-in the ELNA caps. Currently, Nichicon Muse BP has more sparkle in highs.
For opamp adapter bypass cap I will try it
Yes that is the sound signature of Muses. Also Muse KZ (black, polarised for power supply) has it. I personally love that distortion (*), but it is a matter of taste and combination with other parts, as laways. For example, bypassing the LME49720 sounded better with Silmics RFS than with Muses KZ. That's why I guess they will be nice on your SMD adapter. And Muses mix very nice with bright and up-front sound, which emphasise even more. Or when you actually want more musical distortion. Maybe the Silmics will better underline the sound of PFFB amp, and Muses the non-PFFB version.
(*) I have Muses all over my DAC with CS4398, maybe 20 of them, and that sound gives me constant goosebumps, and I love it
ppppp.. Ok so i attached 10uF silmic IIs to the underside of my 3e-audio amp board where the op-amp mounting pins come through. I'll give them time to burn in and then I'll see if anything magical happens as i roll through all the op-amps Im trying out.
Cheers, Pete
If some of your opamps tend to sound bright, compressed or stressed (especially when it is true not by the opamp itself but because of the circuit it is used in), then correctly bypassing it will provide more stable power source with less oscillations, which should be hearable as "cleaner" sound. That's the purpose of this bypass cap - to clean things up by nice way. No reason to expect some different kind of "magic" here.
If you want to hear more of Silmic's character, use two 100uF or 220uF as opamp's power supply cap - one from pin 4 to ground and one from pin 8 to ground (replacing the original electrolytes). But there are often also some small 1nF-220nF decoupling caps surrounding the opamp, which create combo/tandem with big electrolyte, so acoustic results of the whole combo may vary.
If you want to hear more of Silmic's character, use two 100uF or 220uF as opamp's power supply cap - one from pin 4 to ground and one from pin 8 to ground (replacing the original electrolytes). But there are often also some small 1nF-220nF decoupling caps surrounding the opamp, which create combo/tandem with big electrolyte, so acoustic results of the whole combo may vary.
Hi guys. I'm contemplating ordering one of your amps Lester. Probably option c. Currently I use a 3e Audio 3255 2 channel. Powered at 48v from a 'stiff' unregulated psu. 525VA 35v transformer into lots of capacitance. Seems to work well and the amp sounds great but I think Ibwiuld like to try a different...better maybe board. I do think the output inductors are marginal on the 3e and at 48V/4ohm. They get mighty warm.
I feed the 3255 from a Salas DCG3 preamp that I think is set to 1.5x gain. I believe the 3e amp has 20db gain and I see yours has 10db. Will I hear a drastic reduction in output with your amp.?
I can alter the gain setting resistors in the preamp if I need to.
My speakers are nearer 4 ohm nominal. Is your amp OK with lower impedance speakers and 48v.? I don't do 'party's volumes and have a small ish living room.
I feed the 3255 from a Salas DCG3 preamp that I think is set to 1.5x gain. I believe the 3e amp has 20db gain and I see yours has 10db. Will I hear a drastic reduction in output with your amp.?
I can alter the gain setting resistors in the preamp if I need to.
My speakers are nearer 4 ohm nominal. Is your amp OK with lower impedance speakers and 48v.? I don't do 'party's volumes and have a small ish living room.
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Deleted member 148505
Yes that is the sound signature of Muses. Also Muse KZ (black, polarised for power supply) has it. I personally love that distortion (*), but it is a matter of taste and combination with other parts, as laways. For example, bypassing the LME49720 sounded better with Silmics RFS than with Muses KZ. That's why I guess they will be nice on your SMD adapter. And Muses mix very nice with bright and up-front sound, which emphasise even more. Or when you actually want more musical distortion. Maybe the Silmics will better underline the sound of PFFB amp, and Muses the non-PFFB version.
(*) I have Muses all over my DAC with CS4398, maybe 20 of them, and that sound gives me constant goosebumps, and I love it
Nice we got the same impression on the sound of Muse caps.
Sometimes my head quickly turns to the amp and speakers when I heard a superb music passage that's being played.
I will try a combination of Muse + Silmic II . Silmic II has a transparent sound, I find it flat sounding, but recently the bass is becoming stronger.
I can't find bipolar version of it online so I'm using the polarized caps.
You need to run your 3eAudio module at around 36V to 43V DC in order to reduce the heat from the inductors.
If you are listening to your music at 10 o'clock, in my PFFB you need to set it at 12 o'clock to get the same loudness.
JLE PFFB module requires 2.93Vrms to get ~32Vrms output, so with your preamp set to 1.5x gain, you need a 2Vrms source to get 32Vrms output.
I think your Salas DCG3 preamp can output more than 3Vrms right?
The amp is good for 4 ohms load.
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Deleted member 148505
If your preamp has 2x gain, you need 1.5Vrms source to drive it to 260W. I think 1.5 to 2 gain is just right, you can run your preamp at higher vrms output in normal listening conditions.
Not trying to defend the seller but the tone of your chat is provocative. You will just both lose your time and energy if you will continue the conversation. Store's admin looks unprofessional.
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