I thought i had the perfect small class d amp, the latest version of a Fosi audio TDA7498e mini power amplifier
It doesn't have a ton of power but it's actually okay for my 8 ohm 85db rated speakers after i haven gotten use to the sound and power
It doesn't have bluetooth and tone controls (don't need it)
It's has no pop sound when turning the amp on and off and theres no channel imbalance.
What it actually has is some static noise when i adjust the volume, not always and not the entire rang from low to the max range, still from time to time noticeable when there is music playing (when i touch the case when adjusting the volume there isn't any noise). Which i just found out after i bought a 24v 10a power supply as the most powerful power supply suggested by fosi amp for the TDA7498E amp they make
Fosi audio reply (it's not by me accepted as a 100% acceptable answer, should be possible to make the amp without the static noise).
It's normal that when you turn the volume up or down, there is some static noise from the speakers, but once you stop spinning, the noise disappears.
It's the ground issue because the volume knob is made of aluminum
It's tricking my ocd, my cheap Tube T1 tube buffer don't suffer from static noise adjusting the volume and im not even tricked by the fact that the fosi amp isn't black and all of my other unit's are but i have problem with the noise that can be noticeable when i adjust the volume.
Shure i can just use the tube amp to adjust the volume, i used the amp without the tube buffer and stil liked the sound and would have like to use it without the tube buffer for a longer period
The perfect mini class d power amplifier for my needs must have more more than 2x20 in 8ohm with less or max 1% thd
No pop noise when i turn the amp on and off
No noise when i adjust the volume
No channel imbalance
under 100 euros with shipping
Does such an amp exist ?
I must admit i like the sound from my fosi amp, i just don't like the noise i sometimes percive when i adjust the volume
It doesn't have a ton of power but it's actually okay for my 8 ohm 85db rated speakers after i haven gotten use to the sound and power
It doesn't have bluetooth and tone controls (don't need it)
It's has no pop sound when turning the amp on and off and theres no channel imbalance.
What it actually has is some static noise when i adjust the volume, not always and not the entire rang from low to the max range, still from time to time noticeable when there is music playing (when i touch the case when adjusting the volume there isn't any noise). Which i just found out after i bought a 24v 10a power supply as the most powerful power supply suggested by fosi amp for the TDA7498E amp they make
Fosi audio reply (it's not by me accepted as a 100% acceptable answer, should be possible to make the amp without the static noise).
It's normal that when you turn the volume up or down, there is some static noise from the speakers, but once you stop spinning, the noise disappears.
It's the ground issue because the volume knob is made of aluminum
It's tricking my ocd, my cheap Tube T1 tube buffer don't suffer from static noise adjusting the volume and im not even tricked by the fact that the fosi amp isn't black and all of my other unit's are but i have problem with the noise that can be noticeable when i adjust the volume.
Shure i can just use the tube amp to adjust the volume, i used the amp without the tube buffer and stil liked the sound and would have like to use it without the tube buffer for a longer period
The perfect mini class d power amplifier for my needs must have more more than 2x20 in 8ohm with less or max 1% thd
No pop noise when i turn the amp on and off
No noise when i adjust the volume
No channel imbalance
under 100 euros with shipping
Does such an amp exist ?
I must admit i like the sound from my fosi amp, i just don't like the noise i sometimes percive when i adjust the volume
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Yes, fosi audio say the static noise i sometimes hear is normal
I just happen to notice there isn't any noise when i touch the case when adjusting the volume (to me it indicates grounding,earth problem)
Had i know more about the amp and the noisy potentiometer and that it's normal, i might not have ordered a 24v 10a power supply from aliexpress but used the money to buy a different amp or use it to try to fix the problem (if possible, fosi audio did say it's normal).
For now i have just ignored the power the amp has as long as it's above 2x20 watt in 8 ohm with less than 1% thd
I do like my class d amp so much i willing to sell my old powerful denon a/b amp to go all in for class d
If volume is fixed for my amp i can use my tube buffer to adjust the volume with NO static noise, i just know it's there and i would have liked it to work flawless since there is no pop noise when i turn the amp on/off and theres no channel imbalance
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Try to connect a wire between safety earth and one of input rca ground of tube buffer and see if the problem persists... or fixed.
OMG i can't belive it, i tried the platic knob from my tube buffer
It is because it an aluminium knob, i don't have the problem anymore
I NEED A NEW VOLUME KNOB
It is because it an aluminium knob, i don't have the problem anymore
I NEED A NEW VOLUME KNOB
A simple black or grey volume knob in plastic (grey prefered) where do i find one? 20mm long 20mm i diameter
This one i also can get in my country, i just don't have no idea what it's made of
Assortment of 11 Buttons Notched Shaft O6mm Black - Audiophonics
This one i also can get in my country, i just don't have no idea what it's made of
Assortment of 11 Buttons Notched Shaft O6mm Black - Audiophonics
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Isn't it just the back of the knob that gets in touch with the chassis?
Would it not be sufficient to grind away a bit of the material, or perhaps coat the area touching the chassis with plastic?
You can probably test this with a little bit of tape.
Would it not be sufficient to grind away a bit of the material, or perhaps coat the area touching the chassis with plastic?
You can probably test this with a little bit of tape.
No, also the ripped connection on the potetiometer touches the knob and the case + the screw.
Just a random potentiometer
I have tried for hours to find something that is made out of something else than aluminium (havn't looked so much for knobs made out of wood)
Something very basic but stylis like this (it's made of aluminium) 20x20mm
Even when the fix is extreme easy i couldn't find what i need, im okay with a black knob but prefer grey
Dropbox - VID_20200822_125412.mp4 - Simplify your life
But it has attributes that you and a lot of other people wont like, that it's I2S (via DIY) and BT input, so all the analog stuff is simply, off the table.
It's like living in a different world, audio wise.
To my ears, such amplifiers I'd call pretty transparent. If you're sick and tired of scratchy analog controls and connections, any small hum or buzz that's difficult to get rid of, worried about how cables sound and if there's really a difference between 99% oxygen-free copper, you can trade off all that for transparency. As in 25W / channel of Power DAC converters, where the signal stays digital from the recording to the speaker terminals. X4.
Check out the Zoudio amp on the Vendor's Bazaar page. I think it can do all your requirements - with caveats. I have two such "all digital signal path" systems, both using DSP - the Zoudio one occurring in the TAS amp chip itself, the rPi one, I'm using an EQ. I'm wholly taken from the land of the soldering iron to that of keyboard & mouse. I see a nice set of foil caps for nothing and think "Why would I want those?
From my experience, from the one that I have - the Zoudio and a HifiBerry AMP2 - these style amps are very well behaved operationally - the Pi being entirely Webpage GUI based, while the Zoudio has a physical knob and buttons. (You normally set-and-forget the Zoudio using its Windows app GUI) The knob rotational control is a digital device and assigned to volume level.
The AMP2 is paired with the Raspberry Pi 3B to form a complete music system. The Zoudio pairs (using BT) with anything I want as input. Imagine "pairing" your TT with an amplifier. That could be done.
Like I said it's like living in another world. I just happen to like the way it sounds there. I'm using FR speakers in both setups, with woofers assisting and they both sound great. All my audio collection is digital, even though I do still have a few records, player and tube amplifier. They're in storage -
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The Zoudio amp is very good.
IMO with it, DIY is both affordable and easy, it's a fantastic fully configurable DSP + 4 channel amp first step into all sorts of speaker building.
Value for money.
IMO with it, DIY is both affordable and easy, it's a fantastic fully configurable DSP + 4 channel amp first step into all sorts of speaker building.
Value for money.
Suitable plastic knobs are the spare knobs of Les Paul Guitars, for instance. The next music shop is your source😉
Btw: Guitar equipment powered by 2-prong wall warts is a no-go. Replace your wall wart by some 3-prong notebook-adapter and the problem will be solved.
Btw: Guitar equipment powered by 2-prong wall warts is a no-go. Replace your wall wart by some 3-prong notebook-adapter and the problem will be solved.
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