If any of the WIMA caps are polyester (Mylar), replace them with polypropylene caps
of the same uF and voltage values. You won't be sorry.
of the same uF and voltage values. You won't be sorry.
Yes i know, but i start with this because valhalla is what i have in this moment. I know the digital stuff, but its not the same. And tô be honest with you i like the color this valhalla has. If i get this sound only a bit cleaner would be Nice. What do u suggest me? Can i make valhalla sounds cleaner, i mean, less noisy, not less distorted... The distortion is great but the noise is considerably high.
WIMA has pp types, but you'll regardless need a brand made for pcb mount for them to have any chance
of fitting. Mylar usually sounds pretty dirty in comparison. Can you list the WIMA parts numbers printed
on the caps? They may be pp types already.
Interesting! Thanks!
Beside capacitor, what else can be changed for a less noisy sound? Remember that i dont need to keep It inside original enclosure, then bigger parts can be used.
Thanks!
Build a simple common cathode amplification stage with a variable bias so you can move the harmonic signature until you get the sound you are looking for.
Build it with input and output signal transformers, or balanced, or both.
Build it with a suitably stable and well-regulated power supply.
Feel free to throw expensive caps and resistors at it - it won't change the sound any but you will think it does and that's what matters.
Paint the case matt black and install a square blue LED power light.
Only a couple of these suggestions are valid and serious. You could do some study to find out which ones.
Build it with input and output signal transformers, or balanced, or both.
Build it with a suitably stable and well-regulated power supply.
Feel free to throw expensive caps and resistors at it - it won't change the sound any but you will think it does and that's what matters.
Paint the case matt black and install a square blue LED power light.
Only a couple of these suggestions are valid and serious. You could do some study to find out which ones.
Need a schematic to look at that. If you want to use it at the maximum volume setting,
a fair amount of noise might be expected.
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Oh Man, that sounds exactly what im looking for. Please Tell me more about it! 😀
Back up a bit. If the Schiit is noisy in your set up now it might be the set up, not the Schiit. A headphone amp is essentially a line stage with extra current output capabilities. How is the Schiit for noise if you use it in a simple playback system? Source, Schiit, power amp, speakers. If in a basic system it sounds OK, maybe the other setup is the problem. Maybe the Schiit is in the wrong place in your recording chain. Describe your setup.
S.
S.
No, actually i have a good audio setup, with good converters. Im pretty sure the noise im measuring come from valhalla. Also i Saw a reviews that measures valhalla and its match with what im checking here. Its not a super audible noise or hum, no. But there is a lot of noise around -40. And as I said, i like How It sounds, i Just want to try make this STN ratio bigger.
What about electrolytic capacitors? Can i get some improvement changing those? Where does this noise come from? How can i reduce It? In valhalla 2 they did reduce the noise... Its a twice STN ratio bigger
What about electrolytic capacitors? Can i get some improvement changing those? Where does this noise come from? How can i reduce It? In valhalla 2 they did reduce the noise... Its a twice STN ratio bigger
Hello folks, I'm back to this project.
I really like how Valhalla sounds, I like the color and tone, but I want to let it less noisy. I have measures the signal to noise ratio, and it's around -45, and also produces a very low frequency around 10hz. The noise and the 10hz I can measure even with the amp volume all way down. It's the electrical noise floor I suppose.
*the amp is connected to an electrical network without ground, does it can be influencing the noise?
I gonna list the upgrades I'm thinking to do and would like to have you guys opinions.
1- change enclosure to use bigger parts if needed.
2- changing tubes for better and less noisy ones (want try ecc88s)
3- change signal path capacitors. The circuit has 4x wima 0.68uf 250v, and 2x 0.1uf 250v
4- change electrolytic capacitors (6x 470uf 250v)
5- change power transformers and (if better) make it external. The current transformers are solder straight to the board.
6- adding input and output audio transformers to make ins and outs balanced.
Well, that's all I'm thinking to do to get the cleanest possible sound from this amp.
It would be great to have tips and suggestions on all these possibilities. Which of these upgrades you guys think will make a bigger difference?
Thanks!
I really like how Valhalla sounds, I like the color and tone, but I want to let it less noisy. I have measures the signal to noise ratio, and it's around -45, and also produces a very low frequency around 10hz. The noise and the 10hz I can measure even with the amp volume all way down. It's the electrical noise floor I suppose.
*the amp is connected to an electrical network without ground, does it can be influencing the noise?
I gonna list the upgrades I'm thinking to do and would like to have you guys opinions.
1- change enclosure to use bigger parts if needed.
2- changing tubes for better and less noisy ones (want try ecc88s)
3- change signal path capacitors. The circuit has 4x wima 0.68uf 250v, and 2x 0.1uf 250v
4- change electrolytic capacitors (6x 470uf 250v)
5- change power transformers and (if better) make it external. The current transformers are solder straight to the board.
6- adding input and output audio transformers to make ins and outs balanced.
Well, that's all I'm thinking to do to get the cleanest possible sound from this amp.
It would be great to have tips and suggestions on all these possibilities. Which of these upgrades you guys think will make a bigger difference?
Thanks!
I certainly would try changing tubes first. Not so much because you might have noisy ones but because switching from Russian to Western tubes will certainly lighten the load on the heater transformer (cut it by half almost). You might be running high with the heaters voltage in that case so you'll maybe need to add a power resistor in serie to drop the voltage a bit if needed.
A more radical mod would be to switch to a DC heaters supply, which could be necessary if the layout of the pcb isn't too good when it comes to heaters. It would have to be external and you will need a bigger transformer.
The HV supply looks fine at first sight, I wouldn't bother at that point. Same thing with coupling caps, changing them won't solve your problems.
A more radical mod would be to switch to a DC heaters supply, which could be necessary if the layout of the pcb isn't too good when it comes to heaters. It would have to be external and you will need a bigger transformer.
The HV supply looks fine at first sight, I wouldn't bother at that point. Same thing with coupling caps, changing them won't solve your problems.
Yes, ground the outlet you're using.
None of the changes you're discussing will do much regarding the noise issue.
If you want to play around with different parts, you're much better off building or buying something that's point-to-point wired. It's very, very likely that you'll damage the PC board doing what you're attempting to do, then you'll be left with nothing.
Schiit lists the SNR at 98+dB, so there's likely an external influence causing the issues that you're having.
None of the changes you're discussing will do much regarding the noise issue.
If you want to play around with different parts, you're much better off building or buying something that's point-to-point wired. It's very, very likely that you'll damage the PC board doing what you're attempting to do, then you'll be left with nothing.
Schiit lists the SNR at 98+dB, so there's likely an external influence causing the issues that you're having.
It's been measured at much worse than that: Review and Measurements of Schiit Valhalla Amp | Audio Science Review (ASR) Forum
Actually 98+ is the valhalla 2. Mine is version one and the oficial STN is 43+dB. Which matches with what im measuring here.
But yes i gonna try grounding the outlet.
Where all this noise come from? Does the Power Transformers influences the noise floor? I not sure If this circuit runs with AC or DC power. Removing the transformers from the board would help something? Making this as a external Power supply.
Thanks
Why would someone measure SNR at .050V on an amp that could swing 100x that. I also don't agree with adding THD into the noise specs. These are measurements that might make more sense for an opamp based phono preamp with 50dB of feedback.
The power supply noise is 80dB down from the fundamental. That's what's heard as noise.
The power supply noise is 80dB down from the fundamental. That's what's heard as noise.
I just looked at the specs on the website for the Valhalla 1, and it's still 98dB referenced to 1V.
Can you post an FFT shot of the noisefloor?
The power transformers being the noise source is somewhat possible, but unlikely. It looks like maybe the board has DC heater power built in.
Probably not.
Again, if you want to muck around with parts and transformers, don't do it to a built amp on a PC board. Start from scratch and build something with a lot of room.
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Yes those specs on their website are from valhalla 2. The site doesnt mention the number two but its the New one which they are selling nowadays. Valhalla 1 has a higher noise floor indeed.
The tubes are the same in both versions. What they probably did to reduce that much the STN?
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