Is there a consensus on Choke (C-7X) + Caps (Mundorf 250v) upgade on Basic Crack

[Coldsnap]

I love the way the basic crack sounds. But can't really help myself in looking at upgrades. I have a speedball crack too and my preference is the basic crack. I was thinking of doing the popular Choke (C-7X) + Caps (Mundorf 250v) mod, but I cannot for the life of me triangulate how they actually will change the sound? Ideally the Choke would cleanup any noise I have and give me a blacker background and the Caps would make the sound even more grunty for rock. Can anyone with experience help here? Thanks!

[Paul Birkeland]

If you can hear 120Hz power supply noise, the choke will decrease that.  The caps are an improvement in signal handling components.  Both modifications have some potential to cause reliability issues and will likely make your kit more difficult to ship without breaking.

The Crack-a-two-a has proper mounting points for large 100uF film caps and a shunt regulated power supply that does what a choke would do, but several orders of magnitude better.

[Coldsnap]

If you can hear 120Hz power supply noise, the choke will decrease that.  The caps are an improvement in signal handling components.  Both modifications have some potential to cause reliability issues and will likely make your kit more difficult to ship without breaking.

The Crack-a-two-a has proper mounting points for large 100uF film caps and a shunt regulated power supply that does what a choke would do, but several orders of magnitude better.

Hi Paul, cheers thanks for that. What does the choke and caps do for reliability issues? Curious about this, as I'd like my Crack basic to just work 100% of the time for awhile.

With the Crack-a-two, I have a Speedball crack and also proper high end tube amps. I really like having the basic crack around as it's the best amp for just relaxing listening, it's extremely smooth and easy listening.

[Paul Birkeland]

There isn't a great way to mount the caps, and the terminal strips in the amp can't support their weight.  In the C2A, we have adhesive cable tie anchors that are also screwed to the chassis, so you have a good way to keep things secure.

The same goes for the choke, though the C7X at least has mounting holes that can be used for fastening, so it's less problematic.

[thekak]

I've been down this road on multiple builds of various components. Recently I reverted my crack with speedball to the stock electrolytics from humongous oil caps. I kept the oil caps on for a year before changing to really build up an intuitive baseline reference.

Want to know what I could hear after switching back?

Not much difference at all.

I happen to be using the choke you're considering as well but didn't revert that as it would have produced a paperweight that I don't need.

Better to spend your money and time tube rolling. Using an adapter to try 6SN7, trying various 6AS7/6080 tubes (the NOS Chatham in that position + any pre-70s RCA are really a "peanut butter and jelly" combination for me).

I listen with HD600 and have various sources.

In fact, to take all this to an extreme, I brought my crack over to a friend's who has an absolutely enormous and overbuilt Pete Millett OTL headphone amp--the Wheatfield HA-1. I'm taking about a 50-60 pound monster with a separate power supply portion shielded with copper, huge motor run capacitors, and so forth. We listened with various sources using HD-800 and the difference was microscopic.

Component upgrades are a helluva drug, as they say, but for all the anxiety over this brand, this dialectic material, silver vs aluminum vs copper leads.... You REALLY are better off just buying or building an entirely different component, with a wildly different circuit, than wasting time and money on modifying the Crack.

Download PSUD II and visualize exactly the difference between the stock PSU and one with the choke.

A more interesting project would be to try a regulated high voltage supply and compare it to the stock CRCRC. Or add a stepped attenuator commune control. (I'm actually describing the Crack-a-Two-A right now!)

If you really like the sound of the stock crack, enjoy it and don't worry about the extra 1-5% you could potentially squeeze out of it. Unless you go to the trouble, you won't be able to A/B test anyway, let alone blind test the comparison. Much wiser to enjoy what you have while you truly enjoy it. You'll know when it's time to scratch the itch and try a new component.

[Drew1d]

I've been down this road on multiple builds of various components. Recently I reverted my crack with speedball to the stock electrolytics from humongous oil caps. I kept the oil caps on for a year before changing to really build up an intuitive baseline reference.

Want to know what I could hear after switching back?

Not much difference at all.

I happen to be using the choke you're considering as well but didn't revert that as it would have produced a paperweight that I don't need.

Better to spend your money and time tube rolling. Using an adapter to try 6SN7, trying various 6AS7/6080 tubes (the NOS Chatham in that position + any pre-70s RCA are really a "peanut butter and jelly" combination for me).

I listen with HD600 and have various sources.

In fact, to take all this to an extreme, I brought my crack over to a friend's who has an absolutely enormous and overbuilt Pete Millett OTL headphone amp--the Wheatfield HA-1. I'm taking about a 50-60 pound monster with a separate power supply portion shielded with copper, huge motor run capacitors, and so forth. We listened with various sources using HD-800 and the difference was microscopic.

Component upgrades are a helluva drug, as they say, but for all the anxiety over this brand, this dialectic material, silver vs aluminum vs copper leads.... You REALLY are better off just buying or building an entirely different component, with a wildly different circuit, than wasting time and money on modifying the Crack.

Download PSUD II and visualize exactly the difference between the stock PSU and one with the choke.

A more interesting project would be to try a regulated high voltage supply and compare it to the stock CRCRC. Or add a stepped attenuator commune control. (I'm actually describing the Crack-a-Two-A right now!)

If you really like the sound of the stock crack, enjoy it and don't worry about the extra 1-5% you could potentially squeeze out of it. Unless you go to the trouble, you won't be able to A/B test anyway, let alone blind test the comparison. Much wiser to enjoy what you have while you truly enjoy it. You'll know when it's time to scratch the itch and try a new component.

It is fun to tinker.   For me it's such a difference listening now with my headphones, that I wonder if the next "thing" will be that dramatic.   I think I'll put your vote in the "No" camp.

But it is fun to tinker. So eventually it will probably happen.  Where, "what if I..." takes hold.  And that scratches a different itch, so to speak.

[2wo]

Adding the choke is a pretty inexpensive experiment as long as you have a good way to mount it ...John

[Mucker]

I used these 25mm nylon spacers from Mouser and very happy with the fit of the choke. Better yet, the amp is dead quiet.

https://www.mouser.com/ProductDetail/Schurter/9642.5200?qs=vD8Ch%2FBYqOgD22lREtUw1A%3D%3D&countrycode=US&currencycode=USD

I wanted the choke to be isolated from the plate.

Needs M4 bolts for attaching to plate.

I then ran a a ground wire from the Choke mounting bolt to Terminal 16.

Choke wiring was to Terminals 15 and 21.

One has to be careful when drilling holes. The are awfully close to the transformer.

[2wo]

That looks like an eligent solution  ...John

[Mucker]

You are too kind John ... I am like a bull in a china shop and ham-fisted. It's a bit ugly inside, looks respectable outside (I think) but most importantly sings like a canary.