Hello Veysel,
Dunno about the TIP41 I did see it but decided to use this one, a little more expensive but works superbly
https://jlh1969classa.blogspot.com/p/my-build.html
Cheers - J
Hi. Tip41c version page writes 5w per channel but i need 10w per channel. The other link i gave has probably fake bjt outputs.
They probably are as you can’t get the components for that money, however the Tip42C may function but should be replaced as there are better options ( 2N3055 / MJ15003) are probably fake along with the other semi’s & capacitors
If you don’t feel confident in constructing the 69 circuit then it’s an idea !
Ps
just looking at the description leaves some questions so personally I would be cautious especially as I’ve never ordered from aliexpress… don’t think it’s popular with forum members!
Pps
If you looking elsewhere be sure to check out the feedback on the sellers as don’t expect them to arrive within a month if they are from china.
Hello Veysel,
You will not need 10 Watts please look at this page: https://jlh1969classa.blogspot.com/p/watts.html more like 1/64 th of a watt
Cheers - J
Aside:
Doubling the power = 3 dB = nearly nothing, just audible.
Power specification of an amplifier is a vague (by looking measure method determinable) distortion specification only.
Power specification of an amplifier is not a statement about volume, voltage gain, speaker control, sound, audible distortions, audible noise and everything else;-)
The design is so very simple that all kits should be so cheap except that in the first example, the power semis supplied are just too small to result in more than 3-5 watts output. This could be fine for a small desktop or headphones application but not much more. OK, so maybe you have some sensitive speakers that produce good volume with such low power operation but good sensitive speakers are not cheap. So, what you may gain in efficiency, will probably be lost in poor fidelity with cheap speakers.
The first example is just too cheap. Those TO220 power transistors will all likely be close to original TIP41 type which, with generous heatsinks, may be acceptable for output and bias regulator duty but they are a poor choice for the the driver transistor, marked Q2. It should be a much faster type, more so than even the MJE340 shown in the second example (I don't think these suppliers have any clue what's necessary - just cheap). If you expect the amplifier to operate as well or better than the original JLH'69, this is the better kit as it at least comes with full rating, high performance power transistors. I would still experiment with a faster, more suitable driver transistor though. I substituted commonly available 2SD669A (Unisonic) for this app. last time I built one and it now sounds as good as it gets IMO.
The first example is just too cheap. Those TO220 power transistors will all likely be close to original TIP41 type which, with generous heatsinks, may be acceptable for output and bias regulator duty but they are a poor choice for the the driver transistor, marked Q2. It should be a much faster type, more so than even the MJE340 shown in the second example (I don't think these suppliers have any clue what's necessary - just cheap). If you expect the amplifier to operate as well or better than the original JLH'69, this is the better kit as it at least comes with full rating, high performance power transistors. I would still experiment with a faster, more suitable driver transistor though. I substituted commonly available 2SD669A (Unisonic) for this app. last time I built one and it now sounds as good as it gets IMO.
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Yes, the 669A will almost certainly be fake but probably still OK here. KSC3503 is very fast (try at your risk 
) BD135 is an old type of power transistor and also too slow here - BD139 would be better but not the best as a driver. Genuine 2SC5200 will be superb as output transistors. However, the combined effect of too many stages with increased gain could mean oscillation and failure (smoke and flames) so if you have an oscilloscope or other means of detecting instability, use it right from the beginning, at first power-up 
) BD135 is an old type of power transistor and also too slow here - BD139 would be better but not the best as a driver. Genuine 2SC5200 will be superb as output transistors. However, the combined effect of too many stages with increased gain could mean oscillation and failure (smoke and flames) so if you have an oscilloscope or other means of detecting instability, use it right from the beginning, at first power-up I have an oscilloscope but very old Rft brand 20MHz and it shows trapezoid and need repair.
So Jlh design is risky with modern transistors. I only have mj15004 in my hand and mj15003 became extremely expensive here.I Can supply 2n3055 but do not want them.Maybe i should find something in between 2sc5200 and 2n3055.
So as i understand Jlh is stable with fast input and driver transistors and slow output transistors right? I wanted to build them because people say it is better than Amp camp amp.I already have many Aca boards. I will build all and compare with my musician friend ( he bought Focal 714s and wants a class A 5-10 w amplifier but i want to build best one for him too )
So Jlh design is risky with modern transistors. I only have mj15004 in my hand and mj15003 became extremely expensive here.I Can supply 2n3055 but do not want them.Maybe i should find something in between 2sc5200 and 2n3055.
So as i understand Jlh is stable with fast input and driver transistors and slow output transistors right? I wanted to build them because people say it is better than Amp camp amp.I already have many Aca boards. I will build all and compare with my musician friend ( he bought Focal 714s and wants a class A 5-10 w amplifier but i want to build best one for him too )
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I should correct #8851 by saying ST Micro actually make -16 and -10 versions of BD139 which are graded ranges of hFE - good for some driver circuits where gain needs to be controlled by fine tuning and this is why I might choose it. I'm not aware of other types in the TO126 BD series that may also have that option.
Good to know. The last time I saw BD139-16 working well and driving 2 x 2SC5200, was about 10 years ago. The builder was still at school but it sounded great to a group of 9 teenagers who are often quite good judges of sound quality, if only because their HF hearing is better than most adults. Anyway, the guy was so proud, I thought I'd mention it.....
