Try this at CONRAD. I followed the price of a tweeter, their prices are dynamic. Start low and ends high and ar as slow as Reichelt.
Reichelt is most of the times cheaper.
But wait a little bit. Some transistors aren't available. I have several options including one built completely from available trustworthy components (ON Semi). I have already done this but later I have replaced some transistors with CDIL products. I think I have all necessary components to do that again.
I plan to first build one chanel for testing.
Thanks Marcel,Try this at CONRAD. I followed the price of a tweeter, their prices are dynamic. Start low and ends high and ar as slow as Reichelt.
I used to purchase from both Conrad and Reichelt, but Farnell/UK and Mouser/USA are way better and have everything on stock, are fast, and cheaper too. Also, German companies in general arent what they once used to be.
Thanks m0rten. You did a great job, very well organized BOM. Mine are all 'Work in Progress' with many remarks.
I will try to add substitutes and comments on availability of some components.
Guys, use m0rtens BOM.
Thanks @m0rten ,
I think it is the right time to edit the Opening Post and add important stuff there. This scheme along with the BOM should be at the prominent place.
Now, look at the attached table below with parameters of 2SA970 and KSA992. It appears that all transistors can be replaced with these from reliable sources. I am not saying that the existing CDIL are bad but I prefer verified components.
Therefore, I plan to perform the following substitutions:
| 2SA1145 -> KSA1381 2SA970 -> KSA992 2SC2240 -> KSC1845 2SC2705 -> KSC3503 2SD669 -> KSC2690 |
I will report later on on the success/failure of these replacements.
Attachments
Here is the m0rtens BOM from post #642 , in plain view
Hello everyone. Question to our experts. Is it possible to install the A60+ board in a separate case horizontally (2 monoblocks), placing the output stage transistors on the right and left on separate radiators? Will the thermal conditions change significantly? There is only one small temperature stabilization transistor and will be located on one radiator. Of course, all this is connected to each other on a thick chassis. What are your opinions?
I made a relay switch with a remote control to compare 2 amplifiers with switching to one acoustic system. After warming up, blind listening to Dartzeel and A60, 4 people (I’m on fast switching). Cardas interconnect cables, for speakers Kimber Cable 12TC, for the switch all homemade braided 4,2mm section. No winner identified. 2 votes for A60, 2 for Dartzeel. Everyone noted a small difference only in the middle. A60 is brighter, Dartzeel is softer. The only difference is in the connection. Dartzeel played through a pre-Krell with a relay volume control, A60 from the same, but only with a volume control since it has 2 switching outputs with and without pre .The volume is the same. Now I can safely recommend both for production, Dartzeel requires the highest quality components and a good power supply. All the best to everyone.
Hi, It is possible if you have a good thermal conduction between the 2 radiators like a mono bloc radiator or a thick Alu plate (5mm) to fix the radiators. You should place the thermal sensor transistor strategically between the 2 radiators to sensor an average heat dissipation. I think it could be better than one radiator.Hello everyone. Question to our experts. Is it possible to install the A60+ board in a separate case horizontally (2 monoblocks), placing the output stage transistors on the right and left on separate radiators? Will the thermal conditions change significantly? There is only one small temperature stabilization transistor and will be located on one radiator. Of course, all this is connected to each other on a thick chassis. What are your opinions?
Cool the test
Hi all. I haven't written for a long time. I struggled with the sound of this A-60 for a long time. In the process of setting up and listening, I encountered a problem. Long to describe. The long-awaited, expected sound appeared only after bypassing UPC1237 on the board. There is a proposal to cut off everything connected with this protection and move it outside the board.
I have seen them here in Delhi, some people using them, they do it because most of the Toshiba print most often found to be Fake or Chinese reprinted as Toshiba 2SC5200/2SA1943
These ones are from Chinese Manufacturer directly, and they have their own logo as Jilin Sino company,
They said to be considered good enough, I plan to make use of them in my upcoming A60 , I bought these 4 following transistors
2SC5200/2SA1943
2SC4793/2SA1837
Here is a link for teardown of these transistors, Mind the language, it's not in English, it's Hindi language
Have you design PCBs, I like to see, I'm currently looking for a nice amplifier to make, I plan to make my own PCBs design, I need reference design, I gone through this whole thread, and find only PCB design from AliExpress PCBs, not any other,
Have you made your own design or just bought the PCBs and drawn the schematic from it.
Is there any difference between your schematic and PCBs actual schematic
Anyway thank for your schematic,
another thing ,which one is better MA-9S2 clone or A60/A60+
here most of you liked A60