congo5

watch Louis Rossmann - YouTube I used a candle warmer to preheat the area. clean the pads liquid flux tin the pads clean reflux use hot air station solder with silver content helps with gold plating.

yea I always pull up his guides when wiring a chassis but hadn't thought of that in reverse, what happens when the ground gets momentarily flooded with 120vac, waiting for the fuse to blow. bad very bad, just another reason to follow his layout. thanks

BH draws more power and you found the limit of a 3A fuse what reads 120v on your meter from a Variac may be less VRMS than line or ?????????????????????????????????????????

Is it Better? I think it comes down to builders choice. what makes you comfortable. a lower fuse is "safer" for the transformer but will a 2A save a meltdown vrs a 3 or 3.5? if the transformer or our wiring shorts it will blow either size fuse, and neither will protect our amp boards. I have yet to see a picture of Spritzer putting a thermistor in his amps, have you? which two? Two 10R thermistors in series are same as one 20R, Providing they have the same amp rating. I have 5R up to 125R and 2A to 15A nothing wrong with using two to get the resistance value you want or pick one larger one. series though never in parallel Rod Elliott has the best information that I have found on this.

the 0 is ohms (used as jumper) R27,R45 on BOM LRC-LRZ1206LF-R000 think from schematic that AOT is a voltage adjustment I was hoping someone would ask... cause I'm not sure either

its tiny, like 1.5"SQ that works, a bit large, 3A rating with lets say .5A steady state through it. so it will bleed off some voltage it will not get hot enough to lower resistance to stated .48 ohms but doubt you will modulate voltage much with the draw from headphones some have ratings for max surge / or capacitance values it can support so the inrush doesn't kill it. Yes that would be Nice. What I know is from messing with the Uber. Ntc's on the line side help protect the house wiring and all the way through the primary winding and some past that. On the Uber I have two, one 15A NTC per 500va on the primary. But without any on secondary with 188,000uf I kept blowing bridges which when shorted blew the NTC's ,fuses,and melted some wiring. so added the project39 boards on secondary to handle cap inrush current still thinking of adding a rail protection circuit to shut off power to amp boards if problem is detected, also then could add delay on start. something like this: http://wiringradar.blogspot.com/2013/03/short-circuit-protection-for-balanced.html using mosfets for relays http://www.geofex.com/article_folders/ampprot/dcprot.htm

If you were using 400ma and had a 50R thermistor then the drop would be 20v, but is there more to it? is it 10-50 ohms? my general concerns are how to hold the part, (prevent shorts) and protect nearby parts from the heat, 200c do you have part number? when you use too small of one they explode nicely and light up with a nice big spark I have built this and it works, and is nice to bypass any series resistance, if it worries you.

I use the Firstwatt build guides as a reference, so with Kevin's stat amps using 300-400va transformers (In my limited experience) Inrush is probably not needed but do it anyway, and use his .33nf X rated cap also. with fuses I am comfortable with something in the 2-4 amp range, even though it will not protect the circuit boards With the 1000va Uber amp It is Very much needed and I have many blown up parts to prove it. they go on line side right, or are you using them on secondary's? voltage drop would depend on which NTC, they come in all shapes and sizes, just as hard to pick as a transformer check data sheet for your NTC

got the pots today, So Happy! sent fee thanks

they are on the smd version, plug in through hole solder pins and yes jumper them out, use em' or try other buffers, excellent! thanks those connectors will work. if not here somewhere

Trying to figure out a way to make 6 boards manageable, would like some sockets but don't have any yet> sockets for .030 pins with .100" spacing? So the buffers clamp to 18ga wire with normal connectors to take apart you have to work your way in. one power connection stereo in balanced and buffered out, pot could go between the white 3 pin connectors

it was for me, keeping size down and the cost to try it. many choices here, how big do you want it to be? how much are you willing to spend? If you really like it then try the better supply's, fancy Cap's, Or Giant heart stopping defibrillator Caps, on and on...

the GRHV is the best, I used the BHultramini because: It was already built, and its the same size as one of the GRLV single "fat" boards so its smaller, cheaper, and works for 400v.

nice, Very nice!

The diffinput works, files posted , and tested.

this is good news ... payment sent.. paypal address is fine. Thank YOU

Have any of the Song Heui pots shipped? getting close to needing some.

Google?

its from the KGST GB, bhultraminipsv4 I think

Finally... simple enough I can understand some of it. Best $50 I have spent in a long long time (had a few parts already). Having listened for a few hours now, Will describe the sound. Fuck me.

if you don't mind a warm case, this seems to be enough heat sink 3.5" x 9" + case bottom after one hour its 40 degrees rise from ambient 70/110

these are positive tempco devices, as are most things. it does seem more sensitive to rail voltages. Could that be a way to autobias the thing? Do think it sounds better warm I am in awe of the simplicity of the circuit vrs SQ

listening / measuring again. on startup the outputs are positive, which is safe, good. I added a fan to my heatsink plate, lowered temp = lower bias. on start bias is ~13ma and climbs as it warms up. if my fan lets it. which may be why offset is different today. and also running on mains instead of variac. rails at +-394v, outputs to ground are all positive, 10v and under. no adjustment needed here. I call this a Big Win Its to cold to feed ducks, glad I made this. Thanks

if you want someone to test the new layout..........

Working +-399vdc 18.5ma bias lots of gain, power, noise free, good bass. aluminum plate 57C in center after 30min