It's enough to solder from the bottom. If you don't see solder on top, you're likely not feeding solder enough or too slow.

I powered it up! And it works as intended. Without any load I set it to 5,5V and 350mA without any difficulties. Do I have to change anything before I connect it to the Buffalo2, or 5,5V and 350mA means I'm good to go?

I fired it up with the B2. I'm a bit concerned that something is wrong, because the mute led is rlly faint compared to the leds on the Placid, but apart from that it seems fine.

edit: Other thing I noticed, one heatsink on the Placid gets rlly hot while the other one is barely warm. I'm using the 15VA Avel transformer.

Edited by user Friday, January 14, 2011 4:44:18 AM(UTC)  | Reason: Not specified

It's alarming, because now it's winter and the heatsink is in free air :D What will happen during the summer, 35°c combined with casing..

Edited by user Friday, January 14, 2011 6:40:32 AM(UTC)  | Reason: Not specified

You really should be using a fuse from the mains.

Double check your resistance measurements at the pots. the 1.7K measurement is about normal and within the tolerance. The 700ohm measurement is definitely low. Are you sure you have the pots fully adjusted? Be careful not to adjust past the stops.

Yes you can power it up. Just check the output voltage and current before connecting it to the load.

As for the hot heatsinks, It perfectly fine for them to run up into the 50-60C range. But you can adjust the CCS current until the shunted current is 30ma or so and you will be in good shape.

Gabbb,

I would not rest your circuit boards on the antistatic bags while powered up! - I don't know if the metallised coating is on the bag inner or outer surface,but you may well risk a short or at least an inadvertant resistive connection via the bag.

Martin

I'm in the process of ordering parts to upgrade my old Placids to the more "stable" version.
Should the 220pF caps be ceramic as per the original BOM or is it better if I go for MKP that, if I'm not mistaken, are included in current kits?

Thank god the antistatic bag haven't killed anything :)

Currently I have 2 troubling issues with the project. Firstly I don't seem to have the small black connector for the buffalo 2. I assume b2/legato stacking works the same way as b2/small shunt reg. I have the 2x the 3 pins on the Legato, but the pins aint long enough without the black connector and I seem to have a problem finding a replacement part. Is it possible to order a new pair of mini connectors from TPA? In case not I will just have to solder some cables onto the Legato board, however I'm not rlly keen on the idea.

As for the Legato and Placid BP they both run extremly hot (uncomparable to the normal Placid with the buffalo2), the resistors on the legato are in the 60-70c-s which is alarming but I guess it can be used like that, however 2 heatsinks out of the 4 on the Placid are untouchable, my guess is the heatsink is in the 70-80s and the IC is even more and this is still in free air. Current settings are 12 volt and 275mA/rail (anything lower than 275 and there is sag) "We recommend ±12VDC (for best performance and minimized heat) powered by a 15V+15V transformer (available here)." My question is if I lower the voltage to 11V (or even a bit lower), how much will the sound quality suffer and can I expect both the Legato and the Placit both to become colder, or it won't matter much?

I started thinking once the alu case I ordered arrives I create some aluminium pads to transfer some of the heat directly from the heatsinks to the case, alltho I would prefer them to run a bit colder ^^