"Bamboo Project" : Dual Mono 3E Audio 480-1-29A Amplifier

[Hjbct]

So in either case, the DAC acts as the pre-amp ? no other pre-amp needed?

 

[daniboun]

So in either case, the DAC acts as the pre-amp ? no other pre-amp needed?

Right we can say that. I only have this dac on my system.

Do I need a preamp in between my DAC and AMPLIFIER?

Im doing it right now.... RCA out from Geshelli J2 DAC to RCA in on McIntosh 7300 power amplifer. Sounds pretty good. Just wondering if Im missing something. Or if something will soon blow up. If I do need a preamp... The Geshelli has XLR out and the McIntosh has XLR in.... Do you guys...

audiosciencereview.com

 

[Hjbct]

Thanks Dani!

 

[Frider]

Translated by moderator. Please post in English going forward. Thanks!

Good morning

Can we use a classic regulated power supply, transformer + capacitor.

THANKS

 

[brunes]

I got scared by another post of DACs doing max volume...
Made a preamp using a neurochrome universal buffer.
Weak point of a cheap Alps pot...

 

[brunes]

Also, do I understand only at max volume do you get highest output (5v) of the DAC, how do.you do this without a preamp?

 

[daniboun]

Translated by moderator. Please post in English going forward. Thanks!

Good morning

Can we use a classic regulated power supply, transformer + capacitor.

THANKS

Hi
Yes you can use a linear PSU + rectifier board.
Use 43V max for unregulated psu.

 

[daniboun]

Also, do I understand only at max volume do you get highest output (5v) of the DAC, how do.you do this without a preamp?

Checkout attached file from this review

SMSL D-6s Balanced DAC Review

This is a review and detailed measurements of the SMSL D-6s balanced stereo DAC with Bluetooth support. It was sent to me by the company and costs US $199. I was pleasantly surprised with the new industrial design which while minimalistic, manages to impress with its modern style. Love the matt...

audiosciencereview.com

 

[Frider]

thanks Dan

 

[trungdtmc]

I have measured between a PFC LLC power supply and a non-PFC LLC on A07 max, and the result is that the power supply with PFC is noisier, higher THD+N than the non-PFC.

 

[antcollinet]

nd the result is that the power supply with PFC is noisier, higher THD+N than the non-PFC.

That is not a particular surprise. The PFC circuit is of course a switching circuit, and therefore may well introduce additional noise.

However, bear in mind that the result might not be due to the PFC. It is a different PSU, so the overall PSU design might be noisier - or even just component tolerances may be the cause. You also have a test group of only one of each device. Far from enough to draw any conclusions.

Finally : the old adage "correlation is not causation" applies.

 

[Roland68]

I have measured between a PFC LLC power supply and a non-PFC LLC on A07 max, and the result is that the power supply with PFC is noisier, higher THD+N than the non-PFC.
View attachment 360783

Both power supplies look like very cheap Aliexpress (or similar) products. There seem to be very different power supplies.
Are there data sheets for the power supplies?

 

[trungdtmc]

Both power supplies look like very cheap Aliexpress (or similar) products. There seem to be very different power supplies.
Are there data sheets for the power supplies?

I bought both directly from taobao, which is the original supplier and has all the specifications. Aliexpress stores are mostly resellers, like the one where Dan bought it

 

[daniboun]

I have measured between a PFC LLC power supply and a non-PFC LLC on A07 max, and the result is that the power supply with PFC is noisier, higher THD+N than the non-PFC.
View attachment 360783

Dont get me wrong :
The MP-H250S48 is only PFC not LLC...
The other is only LLC. I used it with my first Sylph audio amp too )

 

[daniboun]

That is not a particular surprise. The PFC circuit is of course a switching circuit, and therefore may well introduce additional noise.

Will check this soon ) The Micro audio has no PFC and no LLC circuit. This will tell us if the simpler is the better )

 

[trungdtmc]

Hi Dan

 

[antcollinet]

Will check this soon ) The Micro audio has no PFC and no LLC circuit. This will tell us if the simpler is the better )

Not really - it will only tell you if that particular simple PSU is better

 

[daniboun]

Hi Dan

Chinese sites say anything and everything)

MP-H250S48 SMPS Switching Mode Power Supply Module 250W 48V 5A PFC - Audiophonics

This SMPS MP-H250S48 switch-mode power supply module is capable of delivering 48V voltage and 5A current for 250W of power. It also features PFC (Power Factor Correction).

www.audiophonics.fr

Check here what a LLC + PSU + Soft Start PSU looks like :

"Micro Bamboo Project" : 3E Audio 260-2-29A Stereo amplifier + Micro-Audio PSU

I can't help help but wonder if you aren't looking at this the wrong way. You state that the Mornsun et al. drop in power output when used without fans, but imply that the Micro audio does not, so you ask if this could possibly result in perceived audible effect as stated. The Micro audio will...

audiosciencereview.com

 

[daniboun]

Not really - it will only tell you if that particular simple PSU is better

True ) BTW, the Amplifier is on the way to Germany.
It scares me a little to entrust my amp to a company I don't know but hey... I like taking risks lol

 

[trungdtmc]

Chinese sites say anything and everything)

MP-H250S48 SMPS Switching Mode Power Supply Module 250W 48V 5A PFC - Audiophonics

This SMPS MP-H250S48 switch-mode power supply module is capable of delivering 48V voltage and 5A current for 250W of power. It also features PFC (Power Factor Correction).

www.audiophonics.fr

Check here what a LLC + PSU + Soft Start PSU looks like :

"Micro Bamboo Project" : 3E Audio 260-2-29A Stereo amplifier + Micro-Audio PSU

I can't help help but wonder if you aren't looking at this the wrong way. You state that the Mornsun et al. drop in power output when used without fans, but imply that the Micro audio does not, so you ask if this could possibly result in perceived audible effect as stated. The Micro audio will...

audiosciencereview.com

they are the manufacturers of these power supplies