Hi all,
Just finished my pair of mono M2! It's my second firstwatt amp project after a really successful F5. All i can say is that i'm really pleased by how it sound. Smoother and more relax than the F5. Sound absolutely fantastic on my Tannoys
Thanks to Nelson for the design, teabags for the boards and to everybody that answer all the questions on this thread.
So i have a question for you guys: Checking the voltages on my M2's i have realised that the right channel is biased a little bit hotter than the left channel. I have .61v across the .47ohms resistors on the left channel and .67v on those on the right channel. Any idea what is causing this? The LM385 maybe?? Dc offset is almost 0. Psu voltage is equal on each channel at 24.5v
Hubert
Just finished my pair of mono M2! It's my second firstwatt amp project after a really successful F5. All i can say is that i'm really pleased by how it sound. Smoother and more relax than the F5. Sound absolutely fantastic on my Tannoys
Thanks to Nelson for the design, teabags for the boards and to everybody that answer all the questions on this thread.
So i have a question for you guys: Checking the voltages on my M2's i have realised that the right channel is biased a little bit hotter than the left channel. I have .61v across the .47ohms resistors on the left channel and .67v on those on the right channel. Any idea what is causing this? The LM385 maybe?? Dc offset is almost 0. Psu voltage is equal on each channel at 24.5v
Hubert
Attachments
Thank you! I have bought those on Aliexp. They cost something like 80$ each. Search for the model d-041. I have assembled one in reverse so that I can have a right and a left side.
Here is more photos so that I can have a fugly from Zen Mod
And i know it’s irrelevant sound wise but I will still try to find the cause of the different bias point of each side. It’s not the source resistor for sure so I will start by trying to swap the lm385 Attachments
Mm, pain for me. I tested my Edcors, and I have a dis on one of them. Inspected, and one of the whisker-fine wires is broken on the tab. I tried soldering it, but it seems impossible job. Solder is not taking, so now I am faced with job of getting one all the way from states side, with accompanying shipping costs.
This problem must have happened in shipping since I was very careful on mounting them on the PCBs. Not impressed at all.
Where would be the best place to buy this? Edcor themselves?
Checked Edcor, and their shipping is $57 for an $8 item using USPS Priority mail.
This problem must have happened in shipping since I was very careful on mounting them on the PCBs. Not impressed at all.
Where would be the best place to buy this? Edcor themselves?
Checked Edcor, and their shipping is $57 for an $8 item using USPS Priority mail.
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Hey Henry, i that sucks, i hope you get it fixed. I dont know if it helps you in SA, but Don-Audio sells them in the EU:
Edcor PC600/15K, 16,97 €
Edcor PC600/15K, 16,97 €
I will try again later using my biggest magnifying glass, after drinking enough whiskey to steady my hand, and eating enough carrots to make my eyes focus better.
Thx. Shipping from EU is usually cheaper to SA compared to US.
Must be because postman must work harder to climb over the Trump wall.
Well, just finished delicate operation. I think it was successful.
I first had to remove the transformer from the PCB. That was downright mess, almost disaster. Then I took one solid core strand from butchered HDMI cable and laid it parallel to broken wire after wrapping it around tab, and kept into place with crazy glue (prestik). Then soldered, forming nice bridge over the wires.
Just a warning: those wires are connected with lots of tension to tabs, with no stress relief at all. Be careful when handling these transformers.
Well, tested afterwards, and it seems to be a continuous circuit now.
EDIT: I think I am going to order 2 transformers from Don Audio via slow boat just to have some spares at hand. Just in case.
I first had to remove the transformer from the PCB. That was downright mess, almost disaster. Then I took one solid core strand from butchered HDMI cable and laid it parallel to broken wire after wrapping it around tab, and kept into place with crazy glue (prestik). Then soldered, forming nice bridge over the wires.
Just a warning: those wires are connected with lots of tension to tabs, with no stress relief at all. Be careful when handling these transformers.
Well, tested afterwards, and it seems to be a continuous circuit now.
EDIT: I think I am going to order 2 transformers from Don Audio via slow boat just to have some spares at hand. Just in case.