I just typed in a big long rant about getting a grip on yoursleves over this stuff. Then I deleted it. So I will post a new rant.
I dread to think how many speakers, amplifiers, preamps, crossovers and whatnot I have designed and built. So does my wife
Some of these are / were top of the line, some PA, some middle of the road and some archaic. The strange thing that I have learnt from this is that gross aberrations aside, (which almost always are loudspeaker related):
- Just about any configuration can sound pretty decent.
- Loudspeakers and the room are the #1 issue
- Crossover configuration is equally important, in fact I would say it comes in #0
- Cruddy source material or matching / earthing comes next
- If you are looking at op amps, resistors and capacitors, you are definitely losing the plot
Here is a secret from an old bugger:
- Get a decent bottle of red
- Get a comfy chair
- Get your favourite piece of music
- Stop "listening to the equipment", sit back, have a red and enjoy some music.
If after that, or earlier, you can't stand it then go looking for the gross error in the system.
I dread to think how many speakers, amplifiers, preamps, crossovers and whatnot I have designed and built. So does my wife
Some of these are / were top of the line, some PA, some middle of the road and some archaic. The strange thing that I have learnt from this is that gross aberrations aside, (which almost always are loudspeaker related):
- Just about any configuration can sound pretty decent.
- Loudspeakers and the room are the #1 issue
- Crossover configuration is equally important, in fact I would say it comes in #0
- Cruddy source material or matching / earthing comes next
- If you are looking at op amps, resistors and capacitors, you are definitely losing the plot
Here is a secret from an old bugger:
- Get a decent bottle of red
- Get a comfy chair
- Get your favourite piece of music
- Stop "listening to the equipment", sit back, have a red and enjoy some music.
If after that, or earlier, you can't stand it then go looking for the gross error in the system.
That's what DIY is all about !
Listening to what you made to see if it's what you like. Without that ( DIY) one could pretty happily listen to any kind of system just to enjoy the music !Maybe DIY is a good mental aberration !
We think we can do it even better by spending more time and money ! We ARE driven as we keep going forward (?) but not really sure if it's a closed loop !
I listen to MP3 files often on my 'hi-fi' system ! Very often I don't miss the fidelity of the original uncompressed file. It's only when I sit down to 'seriously' listen to some specific album that I desire 'high fidelity' !
Our minds help us along very often.....often without us realising it. Like when I moved to this house and turned on my old music system it sounded terrible compared to what I was used to in my much larger old house. The acoustics was pretty poor compared to the old place. So I played music much less often. Slowly the duration of playing music increased till now when it's played far more often. Nothing has changed but time has gone by silently ! In the meantime my 'brain' has got used to the system+acoustics of the place and I again enjoy listening to music. The brain did all the adjustments to keep me happy with the existing acoustics ! I know it's flaws but it's automatically accounted for while listening to music ! I just gave it some 'time' .
So DIY is great . Doing a lot of rubbish is also great. Keeps everyone involved and arguing ( 'interacting actively ') about things that probably don't matter at all ! Bottom line is that it bonds people into a huge big family ,sometimes without even having heard their voice or having seen them.
Notice the comments on this forum when members leave this planet ? People do care ! It's a great big happy family, and fighting very often like all good families do !
Great to see that you fit in beautifully !
Cheers !
One thing that one should not forget is that we need some time to adjust to the new sound of the new opamp before reaching a definitive conclusion and also try many different types of recordings. Also, I have found that opamps need some time for break-in when brand new.
I have not tried so many but I know that OPA1612 or 1642 are very good sounding opamps for the price. You can even get free samples from TI...
Good luck
Fab
I have not tried so many but I know that OPA1612 or 1642 are very good sounding opamps for the price. You can even get free samples from TI...
Good luck
Fab
Today I got some time and I checked my Yamaha RX-V667-
Closer look-
DAC section uses some nichicon VR(M) 10uf, some SMG(regular and KZ) and one fine gold series near DAC chip.Is that SMG from United chemi con capacitor?
I cant see ceramic caps.
Power caps are only 6800uf-
Now will changing to better nichicon (from VRM to other series) can improve it much?
please share your views.
Thanks.
An externally hosted image should be here but it was not working when we last tested it.
Closer look-
An externally hosted image should be here but it was not working when we last tested it.
DAC section uses some nichicon VR(M) 10uf, some SMG(regular and KZ) and one fine gold series near DAC chip.Is that SMG from United chemi con capacitor?
I cant see ceramic caps.
Power caps are only 6800uf-
An externally hosted image should be here but it was not working when we last tested it.
Now will changing to better nichicon (from VRM to other series) can improve it much?
please share your views.
Thanks.
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Much? We are usually talking minutiae at best. (A large number of "improvements" have more to do with people fooling themselves, which is something humans are realy good at.) All of these seem to be from reputable Japanese manufacturers. Things may be different in 25 years from now, but my crystal ball is out for service again.
It looks awfully tight around the 6800 µF caps there, which is a bit of a shame as you may not be able to fit anything of higher capacitance (or access the legs for some added bulk capacitance placed elsewhere), and the power supply tends to be the bottleneck in multichannel use in particular. 2x 6800 µF normally is 70 Wpc stereo amp territory, and actually still is a bit tight when it comes to 4 ohm speakers - stereo. I guess they're relying on a sub being used during multichannel operation, which would ease power bandwidth requirements considerably. In a sub-less surround setup, I would expect more than twice the presently installed capacitance to be of use, or at least 50% more if you're in 8-ohm land.
It looks awfully tight around the 6800 µF caps there, which is a bit of a shame as you may not be able to fit anything of higher capacitance (or access the legs for some added bulk capacitance placed elsewhere), and the power supply tends to be the bottleneck in multichannel use in particular. 2x 6800 µF normally is 70 Wpc stereo amp territory, and actually still is a bit tight when it comes to 4 ohm speakers - stereo. I guess they're relying on a sub being used during multichannel operation, which would ease power bandwidth requirements considerably. In a sub-less surround setup, I would expect more than twice the presently installed capacitance to be of use, or at least 50% more if you're in 8-ohm land.
Still if I could add 10000uf caps X 2 will it improve by 20% atleast? Or it will add load on powersupply due to larger values?This Yamaha is said to be 90wpc.
So there can be chance.
Power Transistors are-
An externally hosted image should be here but it was not working when we last tested it.
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Have you addressed the polarized electrolytics in series with the signal path?
You guys are all kidding yourselves if you think that is not an issue.
6800µF per rail cap gives about 90% power supply regulation (60hz line frequency) for a 10KW amplifier driving 8Ω per channel. I have heard excelent sounding amplifiers with half that value (3400µF x2), but they also have good PSRR.
You guys are all kidding yourselves if you think that is not an issue.
6800µF per rail cap gives about 90% power supply regulation (60hz line frequency) for a 10KW amplifier driving 8Ω per channel. I have heard excelent sounding amplifiers with half that value (3400µF x2), but they also have good PSRR.
I am afraid ,but I missed it.There are few as per manual,but it looks non polarized.
An externally hosted image should be here but it was not working when we last tested it.
[/QUOTE]
Like C4225 in series at the entry point of Front Left in above image.
Also C4226 in series at output stage.Do I try replacing them?
Which can be better in that case?
I checked Rotel power amp (RB985) which uses 10000uf X 2 caps per channel. Tptal 10 X 10000uf in 5.1 poweramp. Surprised to see Yamaha AVR using only 6800uf X2 only when its 7.1 channel amp.
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I have recently added 4 x 5600uF to an existing 2 x 6800 uF power supply in a Sony STR-KM3 (5.2 HT) with a huge improvement in overall sound quality.
http://www.diyaudio.com/forums/soli...ur-solid-state-pics-here-409.html#post4347088
http://www.diyaudio.com/forums/soli...ur-solid-state-pics-here-409.html#post4347088
Hi, Regarding the "the polarized electrolytics in series with the signal path?"
As it looks like there is room, I would suggest you replace there polar caps with bi-polar caps that are larger in uf's & voltage rating. This by itself should decrease the distortion from the polar caps to ~1/5th or less of the original amount.
Now if this is something you can hear or not is another question argued about all the time.
Want more info on the use of non polar caps check out the research on caps by Cycil Bateman available on the web. Especially part 4 & 5 of his series.
Regards,
Greg
As it looks like there is room, I would suggest you replace there polar caps with bi-polar caps that are larger in uf's & voltage rating. This by itself should decrease the distortion from the polar caps to ~1/5th or less of the original amount.
Now if this is something you can hear or not is another question argued about all the time.
Want more info on the use of non polar caps check out the research on caps by Cycil Bateman available on the web. Especially part 4 & 5 of his series.
Regards,
Greg
"Like C4225 in series at the entry point of Front Left in above image.
Also C4226 in series at output stage.Do I try replacing them?
Which can be better in that case?"
Those are both polarized electrolytics.
As a bare minimum, I would try and tack a small film cap in parallel.
"Surprised to see Yamaha AVR using only 6800uf X2 only when its 7.1 channel amp. "
That's not big enough if all 7 channels are driven.
For 8Ω at 60hz, you need 3300µF per channel minimum. For 50hz you need 3900µF.
Energy storage goes with the square of the voltage, so a 400W amp with have a rail voltage twice that of a 100W amp, and so the same 3300µF cap will store 4x the energy. Cap values need to be doubled for 4Ω use.
Also C4226 in series at output stage.Do I try replacing them?
Which can be better in that case?"
Those are both polarized electrolytics.
As a bare minimum, I would try and tack a small film cap in parallel.
"Surprised to see Yamaha AVR using only 6800uf X2 only when its 7.1 channel amp. "
That's not big enough if all 7 channels are driven.
For 8Ω at 60hz, you need 3300µF per channel minimum. For 50hz you need 3900µF.
Energy storage goes with the square of the voltage, so a 400W amp with have a rail voltage twice that of a 100W amp, and so the same 3300µF cap will store 4x the energy. Cap values need to be doubled for 4Ω use.
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If I need 3300µF cap per channel,I can try more than 8250µF X 2 in 5.1 setup(not using 7.1 currently).
That is 3300µF X 5= 16500µF or more.
http://theaudiocrafts.com/index.php?route=product/product&path=177_125&product_id=441
Safer side can use 10000µF X 2 something like-
http://theaudiocrafts.com/index.php?route=product/product&path=177_125&product_id=494
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Yes,as per image, C4225 looks polarized electrolytic.
An externally hosted image should be here but it was not working when we last tested it.
Thanks for pointing out.It will be easy to add film cap from other side of pcb.I have also built DIY Super simple preamp which uses better caps in output stage which are not polarized.
http://www.hifivision.com/diy/27074-diy-super-simple-preamp.html
http://www.hifivision.com/preamplifier/57775-burson-supreme-sound-dual-opamp-review.html
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Can you please let me know how to check it?I dont have scope.I usually dont go very loud.Till -15 vol level,sound is reasonably load.
I tried adding only one cap parallel at a time to eitherC4225 or C4226. Cap used was-
An externally hosted image should be here but it was not working when we last tested it.
I tried testing it with headphone out as it was easier way.I added it simple holding in hand and touching the legs of already soldered caps.I also tried it while amp was running(Is that wrong/risky way?). Connected and disconnected.But I couldn't hear any change sound quality.
Usually I can pick the change easily in my Audio technica ATH-M50 headphones.I could in my other DIY projects.The AVR was connected via HDMI only and caps selected were of front channel as headphone was attached.
Now question is was that cap of low value or wrong for this purpose?
Or any other thing to consider?
Another thing I found that there is no Crystal clock near DAC chip-
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Is it ok that DAC (PCM1681pwpr) runs without clock?
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