[tomb]

Quote:

Originally Posted by Beefy /img/forum/go_quote.gif Are they *that* much better than the Muse KZ? Considering it would be the cost of the caps, AND another lot of international shipping?

I can't speak for the Muse KZ's - they're great caps, but too tall for me. However, put some good VitQ's on the output bypasses with Muse ES's, and they come very close to Black Gates. There's no reason the Muse KZ's wouldn't work the same.

That said, the Black Gates are still the best - but you asked the correct question: are they that much better considering the cost?

 

[Beefy]

And I think that the answer is "not better enough for me".

I feel like I've already had my exercise in excess with the M^3. The Muze KZ with Wima bypass should be a good enough start for my venture into valve amps, with the least amount of fuss coming as a kit.

Thanks for the advice folks - even if I did ignore it

 

[fault151]

Yeh thats right we did. I had the buffers at 110. So as long as it ends up at the same 13.5vdc and 27vdc it will be ok?

Thanks for your help.



Quote:

Originally Posted by tomb /img/forum/go_quote.gif Well, correct me if I'm wrong, but we set your bias earlier at 13.5VDC (your supply voltage is 27VDC). The thing is, each of the Millett tubes should be biased at that same value: one-half of the supply voltage. What's different is that the trimmers will need to be turned to a different position to attain that value. So, after changing tubes, plug your DMM into the appropriate tip jacks - one probe in the center ground tip jack and the other probe in the immediately adjacent tip jack, on the right for the Right channel tube and on the left for the Left channel tube. Then turn the appropriate trimmer to adjust the bias. It will never be at 13.5 if you've replaced tubes to a different type, so watch the DMM as you turn the trimmer - you'll be able to quickly tell which way to turn it and how far. If the trimmers were installed in a standard fashion, clockwise will raise the bias voltage and counter-clockwise will lower it.

 

[tomb]

Quote:

Originally Posted by fault151 /img/forum/go_quote.gif Yeh thats right we did. I had the buffers at 110. So as long as it ends up at the same 13.5vdc and 27vdc it will be ok? Thanks for your help.

Yep. Your 27VDC supply voltage won't change in any event, but as soon as you put a different tube in, the 13.5VDC will. This is true even if it's just a different tube of the same type, it's just that the difference won't be as much.

Some of the Amp-Buyer-non-DIY-ers will just switch tubes on a Millett and never re-adjust, accepting the sound for what results (not too good). We're DIY-er's, though, and there's no excuse for not adjusting it back to 13.5VDC every time.

If they're new tubes, remember that bias point will change over time. Just referencing the 12AE6, its bias will continue to drop as the tube breaks in (some of the other tube types may go in a different direction). So, I'd check it every few hours for the first couple of days. If the bias no longer drifts after being turned on for an hour or two, that means the tube is broken-in.

 

[fault151]

Ok then, i'll swap them over and keep checking them. Cheers :0)



Quote:

Originally Posted by tomb /img/forum/go_quote.gif Yep. Your 27VDC supply voltage won't change in any event, but as soon as you put a different tube in, the 13.5VDC will. This is true even if it's just a different tube of the same type, it's just that the difference won't be as much. Some of the Amp-Buyer-non-DIY-ers will just switch tubes on a Millett and never re-adjust, accepting the sound for what results (not too good). We're DIY-er's, though, and there's no excuse for not adjusting it back to 13.5VDC every time. If they're new tubes, remember that bias point will change over time. Just referencing the 12AE6, its bias will continue to drop as the tube breaks in (some of the other tube types may go in a different direction). So, I'd check it every few hours for the first couple of days. If the bias no longer drifts after being turned on for an hour or two, that means the tube is broken-in.

 

[tomb]

I should qualify that statement a bit. Yes, the tubes will be broken-in from the standpoint of bias. However, it can sometimes take a week for subtle things to improve - like slightly harsh highs, etc. It depends on your headphones and the criticality of your listening. But no re-adjustment will ever be required.

 

[xnothingpoetic]

Can someone help these guys find their way home?

I sadly don't know where the positive and negitive leads go on the switch..
I know it's the bottom two but I don't want to reverse it by mistake.

oh yeah: the top left is the switch- the upper right is where the AC adapter plugs into- and the bottom is the MAX board where they connect.

 

[pinkfloyd4ever]

not that it's deficient in performance or anything, but anyone know if there's much performance gain to be had by cranking up the PS & tube bias voltages to say 28v and 14v respectively? or maybe 29 and 14.5? Would this cause shorter tube life?

 

[mik000000]

Quote:

Originally Posted by xnothingpoetic /img/forum/go_quote.gif Can someone help these guys find their way home? I sadly don't know where the positive and negitive leads go on the switch.. I know it's the bottom two but I don't want to reverse it by mistake. oh yeah: the top left is the switch- the upper right is where the AC adapter plugs into- and the bottom is the MAX board where they connect.

the walwart is 24vac so it doesn't matter which way you connect them

 

[tomb]

Quote:

Originally Posted by xnothingpoetic /img/forum/go_quote.gif Can someone help these guys find their way home? <IMG]http://img87.imageshack.us/img87/9573/ohnoesna3.jpg[/IMG> I sadly don't know where the positive and negitive leads go on the switch.. I know it's the bottom two but I don't want to reverse it by mistake. oh yeah: the top left is the switch- the upper right is where the AC adapter plugs into- and the bottom is the MAX board where they connect.

mik000000 is correct, but using your diagram, this is more specific and all that's needed:

 

[tomb]

Quote:

Originally Posted by pinkfloyd4ever /img/forum/go_quote.gif not that it's deficient in performance or anything, but anyone know if there's much performance gain to be had by cranking up the PS & tube bias voltages to say 28v and 14v respectively? or maybe 29 and 14.5? Would this cause shorter tube life?

A tad higher performance. However, you have to be careful that you've got plenty of extra voltage in the supply and that you don't throw the regulator out of regulation. It needs to burn 3V, at least.

Colin's incorporation of the heater resistor prevents the tubes from being over-volted up to 30V. Check the MAX website for the graph on the Tweaks -> Heater Resistor to be sure, but I think 10ohms is enough for safety.

 

[xnothingpoetic]

Thanks for the help guys. I got her up and running again

 

[Marzie]

Quote:

Originally Posted by Beefy /img/forum/go_quote.gif *snip* The kit seems to include everything except for RCA inputs... *snip*

Just FYI, I get my RCA jacks from DIY Fidelity They used to be only $3 or so, they have since TRIPLED the price, but they are on sale now for $6 AUD. I bought 5 pairs of them (last time I bought 3 pairs) and I am thinking about getting more while they are still on sale. I plan on making a switchbox and possibly a dac in the same case... or not... but they are great jacks, imho.

 

[Beefy]

Quote:

Originally Posted by Marzie /img/forum/go_quote.gif Just FYI, I get my RCA jacks from DIY Fidelity

Thanks Marzie, That is handy to know! They've also the same nice RCA plugs used in my Goldenjacks, so I might put in an order.

 

[Marzie]

Listening to the who - Who's Next, it sounds just awesome, I did some of the panel work today, I am disappointed, I may have to widen the front panel jack, it is REALLY hard to plug in my headphones. the jack was lower than the hole (or vice versa), so it was tough to screw the outer part in, now I think I will just have to either get a file or... (this is bad but) take out the drill and drill into it at an angle. Also, because my drill has too small of a chuck for the right size bits, I can't drill the switch or power jack holes either. I might just have someone at work with a cnc mill do the work for me, I think I can just grab the autocad files off the site, anyway this weekend I think I'll get some pics taken so you can say it

EDIT: I posted it here a few days ago, but I am still looking for LEDs. I got a response, but he/she hasn't responded to my pms.

Anyone have any spare blue LEDs?