[Nixon]

Just finished building the Raytheon JAN6418 tube amp kit and fell in love with the tube-y sound. Would just shrink this amp down to make it portable, but the tubes ring like a bell if you knock it. 

Does anyone know if there's a scematic for a amp based around something like a 6111, such as the ALO Audio "The Continental" or a Go-Vibe Porta-tube?

 

[tomb]

Don't know, but I was hoping that at some point, Pete Millett would share his portable Millett Hybrid design with us at some point.  Last time I checked, it was no longer on the market, but I could be wrong about that.  It was most definitely a FOTM for quite some time a couple of years ago.

 

[Nixon]

If he did that, the 6111's would become extinct as fast as the 19J6's did when he published the schematic for the starving student 

 

[Nixon]

Might buy a Muse portable tube amp and mod the heck out of it. Worst case it's only £60 wasted, and even then I should be able to salvage some parts out of it and a nice case.

http://www.head-fi.org/t/567872/muse-portable-tube-amplifier/15#post_7742310

 

[bengoshi2000]

Just finished building the Raytheon JAN6418 tube amp kit and fell in love with the tube-y sound. Would just shrink this amp down to make it portable, but the tubes ring like a bell if you knock it. 

Does anyone know if there's a scematic for a amp based around something like a 6111, such as the ALO Audio "The Continental" or a Go-Vibe Porta-tube?

I've spent a week or so researching the same question and I haven't found anything that beats the Oatley kit in the coveted "affordability & size" categories. I'm giving serious thought to taking the schematic and trying to work a p2p build on a strip board or perfboard. The Oatley PCB seems to have alot of open space. I'm thinking that a closer/tighter layout might get it small enough to make it portable.

That would be considerably cheaper than the Chinese made Muse (which may be of questionable build/component quality).

Would a perfboard Oatley be Cmoy small? Nope, but I think I can get closer...

 

[Nixon]

http://www.head-fi.org/t/453425/tube-headphone-amp-kit-for-25/135#post_6565173

You can get it small enough for a portable amp. Might have issues with microphonics with the tubes unless you damp them really well.

 

[bengoshi2000]

Agreed.  I've got some ideas on "heavy duty damping" that I think will work.  I think that part of the microphonics problem may be coming from the PCB to the tube via the tube wires.  I'm considering some sort of workaround...  I'm also considering photo/camera batteries that would take up less space. 

 

[nikongod]

You should look up siljosae's (spell check, I cant spell) older work. 
He had a few neat layouts for smallish tube amps. 

 

[nikongod]

I think I may have spelled it right! 
Found his gallery:
http://www.headphoneamp.co.kr/ftp/sijosae/Gallery/
 
Nope, I always add an L
Facepalm

 

[bengoshi2000]

Quote:

I think I may have spelled it right! 
Found his gallery:
http://www.headphoneamp.co.kr/ftp/sijosae/Gallery/
 
Nope, I always add an L
Facepalm

I ran across those last week when researching... I'd give my left leg for a schematic of some of the 6111 tube based amps!!!  His 6922 designs look like they might have some heat dissipation issues...
 

 

[Nixon]

Sijosae's amps look amazing. He's posted up some circuits but none of his portable hybrid amps  

 

[Nixon]

Found one that might interest you guys 

http://audiotronics.xanga.com/550800314/item/

He was designing one with a 6111 too but the last post was back in 2007.

http://audiotronics.xanga.com/555817524/item/

 

[Nixon]

Sijosae had posted his schematic over at Headwize but the image link is dead.

http://gilmore2.chem.northwestern.edu/ubb/showpage.php?fnum=3&tid=5878
 
Another Hybrid amp running from 12V
 
http://www.fa-schmidt.de/YAHA/index.htm and the thread over at headwize http://gilmore2.chem.northwestern.edu/ubb/showpage.php?fnum=3&tid=5637 and http://gilmore2.chem.northwestern.edu/ubb/showpage.php?fnum=3&tid=5771&fpage=1
 
Same amp (YAHA) using a 6111
 
http://headwize.com/ubb/showpost.php?fnum=3&tid=5771&pid=65257&fpage=25
 
And a review of small amps
 
http://gilmore2.chem.northwestern.edu/ubb/showpage.php?fnum=3&tid=7447&fpage=1
 
And another one
http://headwize.com/ubb/showpost.php?fnum=3&tid=5771&pid=68791&fpage=27

 

[Fred_fred2004]

I've been messing about with the fa shmidt version, the aim being to get it into an altoids tin this is what I have so far
 

 
Obviously toner transfer
 

 

 
Notice the heatsink has changed orientation in the final version, it is just warm to the touch using 12volts so I think it will be fine in a tin
 
I used a 12AU7 and a JRC4556
 
sounds very nice for a simple project
 
If anyone wants the layout to try their own just drop me a PM I use pcbartist (cos its free)
 
cheers
FRED
 
 

 

[Nixon]

Just ordered a ecc88, a 6111 and 6021 to have a mess around with. Hopefully should be able to knock together the basic YAHA with the ecc88, then shrink it down a bit with the 6111 or 6021 (depending on which sounds nicer). Might replace the LM317 with a more efficient switching regulator to decrease the power draw and hopefully increase the battery life, possible http://www.active-robots.com/anyvolt-dc-dc-converter.html . I'm assuming as the LM317 is used as a tube heater, the noise from it shouldn't be too noticeable.