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Mini Millet (starving student) and iPod??

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I'm brand new to the forum and am just beginning to get up-to-speed on what sounds like the 'wonderful world of tube amps'. Well, that's not entirely true - I've got a Mesa Boogie guitar amp that's one sweet piece of gear, but I'm now interested in reaping the benefits of that buttery-smooth sound for my other music sources.

I'd like to do a very small system in my dining room where an iPod will be the sound source. I came across Pete Millet's Starving Student headphone amp and am wondering how well it would work as an iPod amp.

Anyone have any thoughts or suggestions??

Thanks!
b2
 
Eli -- the starving student (you can see the original here, or the modifications we've been making here) uses a tube for gain and a mosfet source follower on the output, so it does very well with low Z phones.

bsquared -- as a headphone amp, it is a great entry to tubes, though the tubes it uses are gettng tricky to find. As a speaker amp, you might get a portion of a watt to drive very efficient speakers, or you might use it for small desktop speakers, but not much else.
 
As a starving student myself, I'd recommend a spud/compactron amp or a rebuild. Personally, I hit every thrift store, junk yard, scrap yard, antique shop and recycle center in my area until I had a whole pile of tubes, chassis, transformers, etc. Those big record consoles go for cheap (free) when they're broken and sometimes when they aren't. The old magnavoxs are mostly solid state, but the motorolas are golden! Jensen speakers, three channels, and a nice big chassis & over-rated power transformer, all for $0+gas. Some soldering required. Plus, you can always modify & learn as you go.

Also, buy something other than a 'boogie for your next guitar amp :). Hendrix, Berry, Harrison, Django, none of 'em played a boogie far as I know :). Hell I think Kobain played a fender twin as often as his 22. I'd get something point to point wired, since as you figure out tubes, you'll want to modify or redesign it, and the PCB in the boogie won't last long like that.
 
IMO, the "mantra" of triode voltage amplification combined with FET current amplification is highly sensible.

While 19J6s are scarce, the 6J6 is reasonably plentiful. The "Rat Shack" catalog # 273-1365 filament trafo disposes of that need, for a minimal cash outlay. The 19J6 data sheet shows 18.9 V. and 150 mA., for the heater parameters. Ohm's Law tells us that the FET load resistance is 126 Ω. A string of 4X (2 each 30 and 33 Ohms) inexpensive 1 W. Carbon film resistors deals with the requirement. Make sure air flow around the resistor string is GOOD. Failure to do so could lead to durability trouble.


edit: fixed typo
 
m6tt said:
As a starving student myself, I'd recommend a spud/compactron amp or a rebuild. Personally, I hit every thrift store, junk yard, scrap yard, antique shop and recycle center in my area until I had a whole pile of tubes, chassis, transformers, etc. Those big record consoles go for cheap (free) when they're broken and sometimes when they aren't. The old magnavoxs are mostly solid state, but the motorolas are golden! Jensen speakers, three channels, and a nice big chassis & over-rated power transformer, all for $0+gas. Some soldering required. Plus, you can always modify & learn as you go.


What he said.

The M agnavox tube amps are some of my favorite and quite suitable for for ipod use. When you find one that says "Astrosonic", keep walking; those are solid state. That's a good way to screen them on CL too.

The 9300 series amps with the EL-84s are good and the model with a quad of 6V6s is also a good find too. The chassis is spacious enough to allow you to do lots of experimenting.

CD
 
Found one of these selling on ebay for $50. Found the bill of materials for $35. I just finished my first all tube amplifier, using a 50c5, 2 12AT6, and a 35w4 rectifier...Heaters run in series with a dropping resistor...All parts were pulled out of 2 AM radios minus the isolation transformer and chassis...cost me $35 and I sold it 2 days after I made if for $100 at a pawn shop...I'm a 22 year old starving student too
 
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