Alternative to Triad C-7X

[Kitchener]

Title says it all really.
Are there any other chokes one could use instead of the Triad C-7X?

The Triad seems to only be available from US sellers and there is absolutely no way I’m paying $40 for shipping a $10-14 piece of metal.

So are there any alternatives?

Must the choke have 10 Henrys, 90 mA and 270 Ohms?

[Paul Birkeland]

There used to be an identical Hammond part, but I don't see it in their catalog.  The Hammond 157M would be an acceptable substitute.

[Kitchener]

And as it turns out, that Hammond choke is much easier to get a hold of from European sellers.
Thanks a lot, Paul!

I've seen some, well, one Crack modder replace the last PSU cap (220uF) with a lower capacitance film cap (100uF) because the Triad made it possible.
Will the Hammond with its 8H and 100mA do the same?
Not that I'm necessarily thinking of doing this, just maybe!

[Paul Joppa]

I believe the current C7-X is in fact made by Hammond.

[Chris65]

Hammond website lists the 158M as the alternative to the C-7X.
158M specs 10H 100mA DCR 195Ω

[Kitchener]

Well shoot I just ordered the 157M.
Will those 2 missing Henries (what an adorable SI-unit) make much of a difference, you think?

EDIT:
Also, the 158M has 194 Ohms, while the 157M has 259 Ohms. Does this make any difference?
Link to datasheet: https://www.hammfg.com/electronics/transformers/choke/153-159.pdf

[Paul Birkeland]

The 2H isn't a big deal.  You can try a lower value cap as the last cap in the power supply, but I'd recommend trying the stock value first.

[Kitchener]

Is that even possible in the stock Crack base?
The only 220uF 250+V film caps I've seen are massive.
84mm+ diamater seems to be standard for most.
Something like this: FFV 250uF 300V

At least they're not very tall; 40mm. Add 20mm for male plugs, I guess female holes could be used instead to save space.
So theoretically I guess one could suspend them, facing upwards below the transformer/power tube with 60-80mm spacers?


But that cap would cost me about $75, not including shipping.
Aaand surely that's just silly.


I suppose a choke and a cheap film bypass on the last cap is a better solution?

[Doc B.]

I suppose a choke and a cheap film bypass on the last cap is a better solution?

That implies there is a problem that needs to be solved. The better solution might be to roll some different tubes, if you need to change something.

[Kitchener]

Hah, I knew that wording would ensnare someone! 

Naturally I don’t have a technical problem that needs solving.
I have no hum, no noise, no problems.

I just want to tinker.
And all I need is some help in determining how and what is possibe.
And to ensure that I’m not putting in stuff that will have a detrimental effect on the sound or the circuitry of the Crack.
-like countless before me.

[BillD]

Did you try purchasing Triad C-7X from Digikey?   It's about 11 euro compared to the Hammond 158M which is 27 Euro.  Digikey offers free shipping on orders over 50 euro. 

[Kitchener]

Did you try purchasing Triad C-7X from Digikey?   It's about 11 euro compared to the Hammond 158M which is 27 Euro.  Digikey offers free shipping on orders over 50 euro.

I'd love to tell you but I sold that Crack years ago.
I made a post on head-fi when I was done stuffing rubbish into (and onto) that poor amp:
https://www.head-fi.org/threads/crack-bottlehead-otl.476650/post-14204922

The only mod you might want to bother with is the Speedball. But frankly I couldn't hear a difference (certainly not an inprovement) between a stock and Speedballed Crack.

Stay away from boutique parts, it's snake oil.

[Mucker]

In your own words:

"I just want to tinker". 

I think we all do and that's the fun of it.

Bottllehead did all of the hard work figuring out the best parts to use. A stock build is indeed not lacking at all. Keeping the cost under control so us common users can afford audiophile gear is appreciated.

As long as the boutique parts are reasonable, I don't mind tinkering.