G600

Have you tried it with FETs instead of THAT340 ?

Do you see critical resistor, some that will benefit from lower ppm or tolerance ?

Excellent work as usual, JoaMat. Please let us know if you test those values in your working unit ! I'm thinking of populating the SMD resistor with the fine Susumu RG (thin film). Used them in the QRV-08 (Sjostrom). 1206 are 200 V rated and 805 150V, should be plenty.

Kerry's mini PSU are so interesting for such a tiny amp !

Why don't you just buy the thick ceramic pad and a PEEK screw ? No insulation tester, no fried sand and no risk of being transformed in charcoal.

You could extend soldering pleasure by making your own volume control instead of RK50. For example a Seiden 32025 with the matching set of resistor for 10K http://www.goldpt.com/r_series.html You could make 3 for the K50's price.

A lot of fun indeed. Just go slow and double check everything.

+1

Yours is safe. But just take a careful look before starting populating the Beast.

Scary indeed !

Sometimes I hear some random cracks. They come and go, and at some point the channel goes south. Voltages are off, with something like 40 V between the two right batteries, and a very large offset at ouput. It could be cured instantaneously by putting a Voltmeter between battery testpoint and +500V supply entry. Tried to adjust the batteries in many ways, but it comes back anyway. I have also uprated the compensation cap to 15 pF. The amp runs cooler afterwards, but the problems is still happening.

I'm pretty sure I have the same problem too. No devices to test it. But as far as I remember in this topic, it is always the right channel that causes trouble. Mine too. There must be something in the layout, no clue till now.

How much should we bias the EL34 ? Is it 20 mA like the Carbon, or more 25 mA, like the many designs with EL34 ? Or personal taste ?

Was it a Dynahi-powered Beats© ?

Interesting reading. If a black thing looks & tastes like shit, how could that be carbon ?

Just paid !

GRLV @+-15V GRHV @ +459 and +464V Waiting for a few more passive before starting to wire the Thing.

140*70 cm, 5 Kg roughly And not Sumr, but British one-man company with stellar products.

Received the transformer today. Didn't imagine such a big boy. But perfectly built. Changing plans for casing, unless it won't fit. Despite some mistakes and need of adjustment (make the tubes symmetrical for sure), you get the idea :

For sure ! I use the RENY screws I have left from the T2, with spring washers over standard washers. Outstanding stuff from Chemis. The steel screw you can see just holds the board in place.

Drill press madness...

Not built, still waiting for the custom transformer, and a bigger issue is the lack of a drill press and the related skills. Still being a very young padawan in DIY. Need some more weeks before completion.

I'm building it with +-450V supplies. Still a bit afraid of the possible short between B- connection and the feedback trace, like it happened to insanity's Carbon.

It's my only source of wire. Teflon is not easy to strip, but that's not the point.

Amen to that too. I sometimes use another system, but no one beats the hell out of the headphones like the T2. Both Dr Hayashi & Gilmore deserve a thought each time the music starts. PS : my Grounded Grid is coming, gonna be the "portable" little brother...