Tubes amp

[Kippei 0]

[huangyong 0]

squalle, suggest a mod, use LM317 + 4.7ohm as CCS to feed the filament.

[Kippei 0]

I am trying to fit the circuit in this casing

http://sg.farnell.com/jsp/endecaSearch/par...SKU=4273035&N=0

[huangyong 0]

found this:

 

TOROIDS vs. E-CORES ADVANTAGES

 

Toroids:

More compact than E-core design

Materials cost is lower due to single component

Tighter magnetic coupling - lower stray flux leakage

 

E-cores:

Easier to automate winding process

Can be mounted by pins on the bobbins

Easier to isolate electrically multiple windings

Core can be easily gapped to extend energy storage capability

 

stuff to read, it will burn your night!!

http://www.epanorama.net/documents/compone...ansformers.html

[huangyong 0]

experts from DIYaudio said this:

 

http://www.diyaudio.com/forums/showthread....0127&highlight=

[Kippei 0]

Where to buy cheap interconnect?

[squalle 0]

why the 4.7ohm?

 

oh kippei: my board cant fit into that board, but I think you'd be able to fit urs into that case. I've spaced out too much in my worries abt stray EM waves

[squalle 0]

hmm reading from the DIYaudio forum, hence I conclude there's no need to craze all over torroidal

 

the only drawback of EI type trafo is just the leakage flux, which can be dealt with simply by building EM cage around it, cheap and simple

[huangyong 0]

sorry, it should be 4.1ohm.

 

some claims that CCS fed to the filament will gives better sound, but my experince tell me that it will give you quieter and darker backgound when no music playback.

 

using LM317, the voltage across 'out" and "adj" should be 1.25V, put a resistor across them and you will have your Constant Current source. the tube needs around 300mA if I am not wrong, so 1.25 divided by 4.1ohm you should get 300mA.

[squalle 0]

hmm u sure it needs 300mA?

 

those guys at headwize put the filament as 150mA

quote off the headwize forum: "Since the tube is a 12AU7 (12.6V/150mA)"

 

[huangyong 0]

since you guys are building amp, anyone wants to try this..

some cheap mod, good for EI.

 

DaBlock

http://diyparadise.com/dablok.html

 

 

[huangyong 0]

aiya.. forgot u r using 12au7, always tot original SOHA ecc88.

[squalle 0]

since you guys are building amp, anyone wants to try this..

some cheap mod, good for EI.

 

DaBlock

http://diyparadise.com/dablok.html

maybe I'll try that

 

all parts easily obtainable

[Kippei 0]

Holy sh*t.... putting stuff on live

[kross 0]

wa...only a few days and suddenly like so many people building amps.

anyway, after breadborading the amp, i decided to solder it onto the stripboard but something happened, and it didn't work. dunno whether i overheated the transistors or the tube or wat. anyone knows how to check whether the transistors are working or not?