Did you just join this thread? 😛
Domenico published this earlier on. Perhaps even twice. Not counting insignificant imo details it is the same as Shany's first circuit.
What makes this super funny is that apparently someone saw it first here, then posted it on the Hungarian forum and voila - it's back, full circle 😀
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I’ve always wondered what’s the idea behind the two paralleled 100R resistors in the feedback. The only logical explanation I’ve thought of is the fact 458 is offered with “user selectable gain” of 20 or 40 😀
There should be no feedback in dartzeel.
That's what makes the amplifier sound musical.
Yes, i like my clone. But i like F4, M2 and goldmund amps as well.
Each has slightly different flavor, not better or worse than others.
Chinese will steal any intelectual property they can, no doubt about it.
That's what makes the amplifier sound musical.
Yes, i like my clone. But i like F4, M2 and goldmund amps as well.
Each has slightly different flavor, not better or worse than others.
Chinese will steal any intelectual property they can, no doubt about it.
Yes, there is negative feedback loop and it is painfully obvious. However, the feedback is applied “around” the voltage amplification stage only 😎
I joined only a couple/three months ago and have obviously missed a lot
Well, I am happy this schematic has been considered. Looking forward to a functioning 458 clone sometime soon.
only if you make it for sale for profit
no one can stop you to make stuff for personal use
if I take apart accuphase or krell or pass labs and make copy just for myself, no copyright was violated
once you make hundreds or even thousands of illegal copies for sale on ebay or aliexpress, or similar sites, you are violating the copyright law
clear?
Bare 108 PCB
I ordered bare PCB for two set output. Starting from scratch. For the first time ever I will order Dale resistors. I think it will be a good choice for this amplifier.
I ordered bare PCB for two set output. Starting from scratch. For the first time ever I will order Dale resistors. I think it will be a good choice for this amplifier.
The brown Dales such as RN60 are too smooth and dull for my taste. Some people seem to enjoy them while others use them because someone else said so. Rather get a sample and give them a listen. I would rather use generic Chinese metal films in this particular amp. Or even better PRP which are in the same price range as Dale.
I'm a newbie, but I have decided to use metal film Vishay for smaller resistors, Yageo for some resistors where I couldn't find adequate Vishay and TT-electronics wirewound for 3-5W resistors.
Now, analog_sa has confirmed that matching of 2N5551 / 2N5401 is irrelevant. I have personaly also studied this subject and I have concluded that matching of these transistors is indeed loss of time. MJE and MJL transistors have anyway different HF values and matching them seems to be impossible. However, I have read somewhere that this doesn't really affect sound quality.
According to darTZeel, the elimination of Total Harmonic Distortion (THD) "...does not seem to be a determinate factor in the accuracy of reproduced sound."
I think his reasoning is valid from the point of view of a musician. Anyone who played a classical instrument knows that an instrument produces harmonics. Some good musicians even exploit these additional inherent distortions as a way to improove the sound. Take for example a famous british violinist Nigel Kennedy. Or, for those who prefer modern music - just take as an example any good sax player.
Conclusion: I will not even bother thinking about matching transistors for NHB-108. Harmonic distortion is the vital part of its sound.
So, according to my very limited knowledge, the only direction of possible improovement might be selection of capacitors, which in turn appears to be just the matter of taste.
I'm happy that these choices are now behind me and I can go now into my workshop to deal with metal and wood work.
🙂Thank you, but now they are sending green and, according to experts, it is not quite good.
Three types and all different in thickness and coating, the fourth photo I can’t lay out, it doesn’t work, there is no link, only the photo was sent by the merchant with a yellow card. https://aliexpress.ru/item/32805940056.html
https://aliexpress.ru/item/32482673...81-42c4-a230-6906f0328da5&transAbTest=ae803_4
https://aliexpress.ru/item/32909640...9f8d517962c3aacc-1588845574788-02787-VnYZvQVf
https://aliexpress.ru/item/32482673...81-42c4-a230-6906f0328da5&transAbTest=ae803_4
https://aliexpress.ru/item/32909640...9f8d517962c3aacc-1588845574788-02787-VnYZvQVf
adason is right: Chinese are really crooks.
They have created different versions of a copy, of a copy, of a copy ... of DaarTzeel ---> of Revox, and have started selling only "completed" boards made of crap components because it makes more money.
That seller at ebay has a photo of "Yellow" PCB but sells the "green" version, see the photo below, I have made that photo and that's exactly what I've got and it works. From the same seller I have purchased also two pairs of bare Krell KSA-50 board and they work. At least, they all work.
PS: I have tried to upload the photo but upload has failed. But it is green, beleive me.
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Two Amplifier Printed Circuit Board (PCB Size 80 * 115mm, 2.5mmFR4 Plate, Copper Thickness 2 oz, Immersion Gold 4 μm) Such a bare printed circuit board is considered as in the original. https://aliexpress.ru/item/32909640...90975798263320ec-1588861884099-03419-VnYZvQVf
I believe, since I have a photo of green with ebay.
I believe, since I have a photo of green with ebay.
That's exactly what I have: the same board except the silkscreen.
It appears that the Chinese are so crooked that they steal "intelectual property" from other crooks and are in dispute whos clone is 150% better than others. Chinese business, just forget it. 😀
I have also another board with an extra capacitor between R13 and R14. Sounds the same.
Simply, get the board with a single pair, do not change anything, buy genuine parts and solder. Do not even bother with "improoved" clones where they wanted to be "original" with these servo things and all other BS. Just ignore the crookery.
And, by the way: I have noticed the price tag at your Russian AliExpress site. They are charging Russians €155.06 for just a DIY kit. They are ripping you off. I have paid € 74,09 for "complete" pair. Think.
Look >>>HERE<<< I bought that.
Jesus Christ, adason was merciful, Chinese are heavy duty crooks.😡