[tacitapproval]

Quote:

Originally Posted by runeight /img/forum/go_quote.gif So, with no headphones can you please measure the voltages on both leads of R18 on both channels.

3.5mV on R18 L & R.

 

[wiatrob]

Quote:

Originally Posted by sachu /img/forum/go_quote.gif Heh..not as pretty as I could have made it...but I was moving fast on this one.

Were those 4 beers 32 oz. each?

 

[wiatrob]

Quote:

Originally Posted by Nebby /img/forum/go_quote.gif eagerly awaiting my package to show up so I can get started. Best finish my buffalo build first so I have a source though!

They are on the way! In facts, all kits have been shipped. Thanks all for your patience. And to Alex for an incredible design, I was rolling tubes last night... Stuck on an Amperex BB 6DJ8...

 

[wiatrob]

Quote:

Originally Posted by sachu /img/forum/go_quote.gif DO you want me to install the BOM standard coupling caps? OR do you want me to get some fancy caps for them? SNIP There are many options...let me know. I might socket the caps in case you want to try different caps later

Now Sachu, I thought we were going to keep boutique cap options under the radar - I'm keeping the high heater current mod there!

 

[tacitapproval]

Ok, I've fixed my CTH and now know what my aforementioned boneheaded move was. I was using some starquad cable and and managed to get some of the thin, fibrous shielding on the top of the CTH pcb...D'oh!!! I thought I had cleaned it off ok, but apparently not. I went over it more carefully with some needle tweezers and removed some more tiny wires, which must have shorted something. Now it is back playing again. I am very sorry to keep wasting everyone's time and sincerely appreciate the indulgent help I have received.

 

[wiatrob]

Glad to hear it's working! My approach to cleanup was to use compressed air on the top and bottom of the PCB (after de-fluxing or wiring work) along with close visual inspection.

 

[srserl]

My kit was waiting at my door when I got home from work last night and it is going together smoothly. I have everything soldered, but was ready to install the heatsink. The instructions at the Cavalli Audio site says to install the regs and heatsinks, but the bom only has 1 heatsink. Does this single heatsink go on ICP? It looks like the heatsink will need some surgery to make it fit with Q2P,Q3S andQ1P nearby. Removing the bottom fin on each side should allow it to fit.

Scott

 

[sachu]

Quote:

Originally Posted by srserl /img/forum/go_quote.gif My kit was waiting at my door when I got home from work last night and it is going together smoothly. I have everything soldered, but was ready to install the heatsink. The instructions at the Cavalli Audio site says to install the regs and heatsinks, but the bom only has 1 heatsink. Does this single heatsink go on ICP? It looks like the heatsink will need some surgery to make it fit with Q2P,Q3S andQ1P nearby. Removing the bottom fin on each side should allow it to fit. Scott

yes, it is only for ICP, the 24V regulator..and yes you will probably need to do some sugery to get it in there..

 

[wiatrob]

I was able to bend both bottom fins out on one of my builds, but removing them is probably best for clearance. Carefully check vertical placement of ICP when inserted into the case WITH the sink... I ended up placing my first one a bit too high.

If placed correctly, the sink will clear the components, case side and top...

Drat, I wish I had taken more pics of this on the proof build - but I sent it off to HeadphoneAddict...

 

[nux]

Well I can say that the 24v regulator will work without a heatsink for a while, I'd forgotten to put it on. I'm just getting it to fit now, I'll try and get some photos of it up later today to show how to modify the heatsink. The fins bend and snap off pretty easily which is good.

Oh, and it sounds amazing! I tried out a few tubes yesterday, a Sylvania 12AU7, a new Electro-Harmonix 12BH7 and a Mullard 12AU7A which sounds good. Still have a few more to try out.

Just curios, to burn in NOS tubes do you need to have something playing through it, or is it enough to just have it plugged in with the heater going?

 

[wiatrob]

Depends how much of a burn in fanatic you are. I'd say just having it fired up is enough to burn off any impurities in the envelope - but you might want pink noise 'distribute the energy across the spectrum' and give it a real excercise

 

[tacitapproval]

Quote:

Originally Posted by wiatrob /img/forum/go_quote.gif Glad to hear it's working! My approach to cleanup was to use compressed air on the top and bottom of the PCB (after de-fluxing or wiring work) along with close visual inspection.

I still getting some infrequent, random e12 trips while listening, and I have had some transient noise in one channel. I am sure that this means I haven't gotten all of the little shielding wires off the board. Cleaning it is of course complicated by the density of components on the board, as I can't see all of the spaces between leads or even reach them. I have blown a lot of air across it, in addition to tweezing. I wonder if something like magnetic tweezers would help? Is there such a thing? What a mess.

 

[wiatrob]

Tacitapproval,

What values did you use for R1E, R2E, and R4E? I think it was pointed out in this thread, but there were few value changes made in the BoM (2015B) posted on Alex' CTH website (R1E, R2E: 33K, R4E: 2.0K, only 1 to-220 heat sink used in the build).

 

[wiatrob]

Quote:

Originally Posted by tacitapproval /img/forum/go_quote.gif I still getting some infrequent, random e12 trips while listening, and I have had some transient noise in one channel. I am sure that this means I haven't gotten all of the little shielding wires off the board. snip

Immersing the board in alcohol and more air might help locate further strays. Not to be alarmist - but stray bits of wire on a board this dense are rather risky.

These most likely would cause a large puff of smoke and not the symptons you describe. See my previous message about e12 values.

The intermittent noise is more interesting. Do you multiple tubes?

 

[tacitapproval]

Oh, I was working off 2015a not b. I see the relay circuit resistor changes, and will try that. Thanks for the heads up.