Millett "Starving Student" hybrid amp
Dec 26, 2014 at 2:46 PM Post #6,856 of 7,258

KimLaroux

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Pin 4 must be connected to the voltage source in each case.  The heaters are connected within the tube, but you must have 18-19V going through them.  If pin 5 is connected to ground (correct), the only way that will happen is if you connect pin 4 to the voltage source.

 
Actually 12.6 V for a 12AU7 build.
 
The pins are not connected together as there is no dot on the schematic. They need 12.6 V across them. You connect one pin to ground and the other to pin 3 of the MOSFET.
 
Dec 26, 2014 at 5:34 PM Post #6,857 of 7,258

tomb

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Pin 4 must be connected to the voltage source in each case.  The heaters are connected within the tube, but you must have 18-19V going through them.  If pin 5 is connected to ground (correct), the only way that will happen is if you connect pin 4 to the voltage source.

 
Actually 12.6 V for a 12AU7 build.
 
The pins are not connected together as there is no dot on the schematic. They need 12.6 V across them. You connect one pin to ground and the other to pin 3 of the MOSFET.


He posted the schematic for the 17EW8.  That's what I was going by ...
wink.gif

 
Dec 27, 2014 at 12:30 PM Post #6,859 of 7,258

Amatsu

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I'm using the 17EW8 version. I was just re-doing the amp in another enclosure because I didn't like how it sounded before compared to my portable Fiio e6 (bad mids and harsh/piercing highs) and had the feeling something wasn't right. Anyway I finished the new build just now with the same parts, it sounds promising for now but I'll give it a little more time to decide. 
 
Could a bad grounding affect the sound quality or grounding only affects hum/noise?
 
Dec 27, 2014 at 7:58 PM Post #6,861 of 7,258

tomb

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  I'm using the 17EW8 version. I was just re-doing the amp in another enclosure because I didn't like how it sounded before compared to my portable Fiio e6 (bad mids and harsh/piercing highs) and had the feeling something wasn't right. Anyway I finished the new build just now with the same parts, it sounds promising for now but I'll give it a little more time to decide. 
 
Could a bad grounding affect the sound quality or grounding only affects hum/noise?

That's a circular question.  Noise and hum affect sound quality.  Therefore, bad grounding effects sound quality.
 
Dec 27, 2014 at 7:59 PM Post #6,862 of 7,258

tomb

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Well, it turned out that I'm still lacking some parts.  I have them ordered, but it will be a few more days ...


I just saw the kits pop up on your site. Ordered. Looking forward to this project. Thanks!


Yep - processing starts Monday, with shipping soon thereafter.
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Dec 29, 2014 at 3:52 PM Post #6,863 of 7,258

Peridot

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I just saw the kits pop up on your site. Ordered. Looking forward to this project. Thanks!

 
I bought one of these kits from Beezar some years ago and for some inexplicable reason it has remained one of those things 'I must get around to' ever since 
redface.gif

 
Well, having a completely free day today I decided to tackle it. 
 
I have to say that the quality of the components and kitting, together with the superb step by step instructions from tomb, made it one of the most straightforward and rewarding projects I have ever tackled.
 
Good luck to everyone embarking on building the new kits 
smile.gif

 
Dec 29, 2014 at 9:09 PM Post #6,864 of 7,258

tomb

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I just saw the kits pop up on your site. Ordered. Looking forward to this project. Thanks!

 
I bought one of these kits from Beezar some years ago and for some inexplicable reason it has remained one of those things 'I must get around to' ever since 
redface.gif

 
Well, having a completely free day today I decided to tackle it. 
 
I have to say that the quality of the components and kitting, together with the superb step by step instructions from tomb, made it one of the most straightforward and rewarding projects I have ever tackled.
 
Good luck to everyone embarking on building the new kits 
smile.gif


Many thanks for your kind comments.
 
Just to be clear, the new kits are identical in every way except that they have black knobs and the fact that I gave up on labeling every single parts bag.
eek.gif
 
 
Dec 29, 2014 at 9:49 PM Post #6,865 of 7,258

nbkgudx

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Many thanks for your kind comments.
 
Just to be clear, the new kits are identical in every way except that they have black knobs and the fact that I gave up on labeling every single parts bag.
eek.gif
 

Hey Tomb,
 
I just ordered a kit. I'm very excited as this will be my first build. Does this kit come with detailed instructions on how to build it?
 
Dec 29, 2014 at 10:37 PM Post #6,867 of 7,258

tomb

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  Hey Tomb,
 
I just ordered a kit. I'm very excited as this will be my first build. Does this kit come with detailed instructions on how to build it?

Beezar kits won't come with instructions, but you'll find tomb has them comprehensively documented at diyforums.org


Thanks! SSMH Documentation
 
Or ... in this thread: http://www.head-fi.org/t/437075/starving-student-millett-hybrid-pcb-step-by-step-build-guide
(also in my sig)
 
Dec 31, 2014 at 4:23 PM Post #6,868 of 7,258

tomb

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For those who've already ordered - I apologize, but shipping will commence on Friday.  I forgot the connectors that are needed for the power switch.*  I went to several hardware stores in town today (all sold out) until I gave up and went to Fry's.  They had what was needed, but I only got back a little while ago, so I won't be able to get to the Post Office until Friday (closed tomorrow).  It seems there's always a few glitches when trying to start up a big effort like this.  Please be patient.
 
 
* It's best not to solder directly to the tabs on the power switch.  You need to use those pink things in the pic below:
Assy-4-sm.jpg

 

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