Why the asymmetric arrangement? Is that final position or are you going to center and make everything symmetric?
I am pulling a 'Project Binky' fabrication and build a magnetic shielding for the edcor. Here is a pic of the template. It will extend over the board and down to the heatsink for fastening. I bought some 22ga steel sheet at the homestore.
I will probably modify the template slightly and add a four 1/4in lips I can fold over at the corners and solder them.
I will probably modify the template slightly and add a four 1/4in lips I can fold over at the corners and solder them.
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Thanks!
Yes, both trimpots are at the end. If I understand post 3 correctly, the problem isn't uncommon, so I think I'll just go ahead and do the modification.
Those are mono blocks. Transformer is placed as far away from Edcor as possible. I have played them for at long time and they were 100% electrical silent but the toroid's began to have some slight mechanical hum. Then I decided to do something about it and ordered Toroidy transformers. They should also be more electrical silent as they have more shields. They also have a PE-wire (yellow green.....but don't know how it is connected internally). But the main reason for the rebuilt was to get rid of the mechanical humming. Then I got some Schurter filters which almost fits in the hole so I make this "upgrade" also. I think it can't hurt. I have measurements from before rebuild so interesting with a measurement after to check if I see any change in noise/distortion.
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I also have Edcor shielding. I first used copper tape for RF shielding and then mu-metal for magnetic shielding. It goes all the way around. From my distortion measurement the hum level is very low. I also have very low ripple on PSU. Probably the shield does the most and placement of transformer far away.
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@MEPER Thanks! I see. You used a more complex PS seems to be RCLC with resistors and inductors. Can you share the details? What kind of inductor did you use?
The toroidy looks nice is potted that may help with mechanical hum. What secondary voltage and VA do you use?
Can you hear the difference when shielding the edcor?
The toroidy looks nice is potted that may help with mechanical hum. What secondary voltage and VA do you use?
Can you hear the difference when shielding the edcor?
OK! there is slightly mismatch somewhere, maybe the output mosfets. Increasing the trimpot range should fix it. My mosfets were close enough and I didn't give it a second thought.
Will the PSU chokes induce enough EM to affect the input transformer? I know its not AC current (I guess pulsatile would be a better definition?), but I would still like to know if that would be an issue.
I "socketed" C0, but I'm not sure that was a good idea, as it does not sit "rock solid" in the socket, wobbling a bit if you push it. Though the movement feels being only in the top part, the bottom of the legs still should have contact with the socket nests. Any comments, please? It's my first time attempting this.
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Wanted to have a way to easily remove it if I decided to use my M2x with the valve pre-amp at sime time in the future. They say it's easier for the valve pre-amps to drive it without the C0 (??) 
Actually, I did not like this "racionalization" with the sockets myself when looking at it, so thinking of removing it and just soldering C0 on the board. But wanted to hear what more experienced people think about that
Actually, I did not like this "racionalization" with the sockets myself when looking at it, so thinking of removing it and just soldering C0 on the board. But wanted to hear what more experienced people think about that
With my solder tails, or dip sockets, you can feel the leads get into a position which is more snug in the connection When pushed all the way in. The resistors or capacitors will be a little wobbly because they are on long leads, but they fit snugly in the connection. It may be possible that either your leads are too long or that the Solder tails you are using our two big relative to the diameter of the lead.I haven’t had any problems with my connections but your mileage may vary. I even use my connections to be able to swap out different chips on the input board. You should be able to see this in one of my posts in this thread. Of course, if you’re not comfortable with it you can always just solder the part in or out whether you’re using a tube pre-or not. Again, I haven’t had any problems with mine one way or the other I can add some photos if you wish.
Listening review of new daughter cards IPS6 and IPS7
In case the preceding discussions about metalworking and machine tools have made anyone temporarily forget about the First Watt M2x amplifier, I'm taking the liberty of re-posting some comments made by member avdesignguru. I sent him six free PCBs: 3xIPS6 and 3xIPS7, and he stuffed & soldered those daughter cards, then tried them out in his M2x. I would be pleased to send YOU some free PCBs too; please read M2x post #3416 for the details.
Here are avdesignguru's listening evaluations:
In case the preceding discussions about metalworking and machine tools have made anyone temporarily forget about the First Watt M2x amplifier, I'm taking the liberty of re-posting some comments made by member avdesignguru. I sent him six free PCBs: 3xIPS6 and 3xIPS7, and he stuffed & soldered those daughter cards, then tried them out in his M2x. I would be pleased to send YOU some free PCBs too; please read M2x post #3416 for the details.
Here are avdesignguru's listening evaluations:
I am building the IPS7 boards you sent this weekend Mark, thanks. I did go through the PCB order process for the IPS6 boards. I tried hard to use use a US fab company. My brother’s fab company only made stuffed boards. The China based company I ended up with charged 1/3rd of what I could find here in USA, and was faster in promised delivery.
IPS7 and Hakuin boards this weekend, will be enough for my attention.
The Toroidy transformers were supposed to ship this week, but, at the last minute, Hubert discovered they had built 220v transformers, not the 115v I had specified. Another delay for the big rebuild. I need these big transformers to plot placement in the chassis, and figure on the switch location on the anticipated black front panel order.
IPS7 and Hakuin boards this weekend, will be enough for my attention.
The Toroidy transformers were supposed to ship this week, but, at the last minute, Hubert discovered they had built 220v transformers, not the 115v I had specified. Another delay for the big rebuild. I need these big transformers to plot placement in the chassis, and figure on the switch location on the anticipated black front panel order.
I am building the IPS7 boards you sent this weekend Mark, thanks. I did go through the PCB order process for the IPS6 boards. I tried hard to use use a US fab company. My brother’s fab company only made stuffed boards. The China based company I ended up with charged 1/3rd of what I could find here in USA, and was faster in promised delivery.
IPS7 and Hakuin boards this weekend, will be enough for my attention.
The Toroidy transformers were supposed to ship this week, but, at the last minute, Hubert discovered they had built 220v transformers, not the 115v I had specified. Another delay for the big rebuild. I need these big transformers to plot placement in the chassis, and figure on the switch location on the anticipated black front panel order.
IPS7 and Hakuin boards this weekend, will be enough for my attention.
The Toroidy transformers were supposed to ship this week, but, at the last minute, Hubert discovered they had built 220v transformers, not the 115v I had specified. Another delay for the big rebuild. I need these big transformers to plot placement in the chassis, and figure on the switch location on the anticipated black front panel order.
I was initially interested in the ips7 but then your post about the opa1611 got me intrigued and made me consider an IPS7 but with the smd traces and DIP traces like the tucson so I am making that PCB version.
