[spotts29]

The issue had to be most likely on the right channel, since it was the only one affected. Replacing the volume potentiometer, output caps and sockets didn't change anything, so it had to be something in between. Turns out it was that resistor.

Kudos for persistence!

 

[Beefy]

Just giving some brief positive news to close the topic: I finally managed to find the fault.
It was actually the 22k ohm resistance in the right channel, that for some reason was being noisy. Replacing it completely got rid of the issue.
I don't know why the issue wasn't appearing back at the repairmen's places, but I'm willing to say that it was either up to randomness in the issue's appearance or something else.
Either way, thank you everyone for giving advice and support, I appreciate you guys!

I'm glad you found this! What a journey. But you want to know what's funny about this? If you are indeed ready to start seeing the humor in it all?

Spoiler: Funny!

That resistor would (should!) be replaced by the Speedball upgrade.

 

[Cowwe]

I'm glad you found this! What a journey. But you want to know what's funny about this? If you are indeed ready to start seeing the humor in it all?

Spoiler: Funny!

That resistor would (should!) be replaced by the Speedball upgrade.

I had actually thought about just saying "whatever, let's try to solder the speedball on and see if that fixes it" but stopped since it didn't sound like the brightest idea lol.
Either way, I have yet to decide if I want to install the speedball, since I've heard mixed opinions about the changes it brings.

 

[Beefy]

I had actually thought about just saying "whatever, let's try to solder the speedball on and see if that fixes it" but stopped since it didn't sound like the brightest idea lol.
Either way, I have yet to decide if I want to install the speedball, since I've heard mixed opinions about the changes it brings.

Well, for another data point, I think Speedball is absolutely essential.

The stock Crack is tonally good, particularly with phones like the HD650, but it is generally pretty limp and fuzzy. Speedball gives it clarity and detail, and is a huge step up.

 

[Cowwe]

Well, for another data point, I think Speedball is absolutely essential.

The stock Crack is tonally good, particularly with phones like the HD650, but it is generally pretty limp and fuzzy. Speedball gives it clarity and detail, and is a huge step up.

That's good to hear, honestly. I very much enjoy my Crack, but I have an assembled speedball pcb sitting on my desk ready to be soldered on, and I can feel the effects of upgraditis hitting.

 

[dstarr3]

If I remember right, the general wisdom is that if you want to go full on super tube-sounding, base Crack. If you want something cleaner and less tube-y, Speedball.

On that basis, I went for just the base Crack. But with Mr. Bottlehead wanting to retire soon, if he does a final run of Crack kits soon, I might pick up a Crack+Speedball kit just to have one example of each before the era comes to an end.

 

[Beefy]

If I remember right, the general wisdom is that if you want to go full on super tube-sounding, base Crack. If you want something cleaner and less tube-y, Speedball.

On that basis, I went for just the base Crack. But with Mr. Bottlehead wanting to retire soon, if he does a final run of Crack kits soon, I might pick up a Crack+Speedball kit just to have one example of each before the era comes to an end.

UGH, I think a lot of people make a pretty major oversimplification on this point. There's nothing un-tubey about the Speedball, it brings better speed, clarity and detail, while maintaining the same warmth in tone and timbre. People associating slower, duller amps with 'tube sound' is just plain weird.

In terms of upgrades on the Crack, Speedball made by far the largest improvement for me. Second was 5998 tubes (although at current prices, fudge that). Third was output caps and everything else.

 

[Cowwe]

UGH, I think a lot of people make a pretty major oversimplification on this point. There's nothing un-tubey about the Speedball, it brings better speed, clarity and detail, while maintaining the same warmth in tone and timbre. People associating slower, duller amps with 'tube sound' is just plain weird.

In terms of upgrades on the Crack, Speedball made by far the largest improvement for me. Second was 5998 tubes (although at current prices, fudge that). Third was output caps and everything else.

I'm happily listening to some recently obtained 5998's and a pair of new output caps as we speak. I'm thinking I will just go ahead and try the speedball too, and finally see for myself how it is

 

[raindownthunda]

On another note, since during this time I was also suggested to make sure to keep the headphones unplugged while turning on and off the amp, I got to thinking about something else. I don't dig the idea of inserting and extracting the headphone jack at least twice a day (and I do like to switch headphones around), so I was looking for some kind of extension that would take the abuse instead of the amp's own jack input. A 6.3mm female in and 6.3mm male out, maybe curved by 90 degrees so it also stresses the cable a bit less (and doesn't get it to be too tall) .
Does anyone have something like this in mind? I have looked around a bit but didn't find much. Is it a dumb idea?

I don’t think wear is a concern, but I prefer the 90 degree connectors mostly for aesthetics… but they are also slightly easier to unplug since the top plate relies on gravity and can lift up. Not an issue when leaving a right angle adapter plugged in.

Two options:

1. Right angle male to female connector - I have this one and had good results: https://a.co/d/cT3VYpD
2. Right angle pig tail extender. This gives you a little more slack and also can use higher quality connectors. I got this one from a cable maker on Etsy I had a really awesome experience working with them, you can customize the cable length to whatever would work best for your setup. This example is TRS to XLR but I’m sure they could do TRS Male (right angle) to TRS female (straight) if you asked them. Mine was a custom request and since then they’ve added it to their whole page as a regular product: https://www.etsy.com/listing/1009811690/

Here’s what the first adapter looks like with my BHC:

And here’s the second “pigtail extender” option on my BHC - I also went with right angle RCA and a right angle power cord:




edit: I should mention I noticed no difference or degradation in sound quality with either adapter or extender. Personally I don’t think it makes an audible difference unless theres a bad connection in the connector (defective).

 

[Hypops]

I don’t think wear is a concern, but I prefer the 90 degree connectors mostly for aesthetics… but they are also slightly easier to unplug since the top plate relies on gravity and can lift up. Not an issue when leaving a right angle adapter plugged in.

Two options:

1. Right angle male to female connector - I have this one and had good results: https://a.co/d/cT3VYpD
2. Right angle pig tail extender. This gives you a little more slack and also can use higher quality connectors. I got this one from a cable maker on Etsy I had a really awesome experience working with them, you can customize the cable length to whatever would work best for your setup. This example is TRS to XLR but I’m sure they could do TRS Male (right angle) to TRS female (straight) if you asked them. Mine was a custom request and since then they’ve added it to their whole page as a regular product: https://www.etsy.com/listing/1009811690/

Here’s what the first adapter looks like with my BHC:


And here’s the second “pigtail extender” option on my BHC - I also went with right angle RCA and a right angle power cord:




edit: I should mention I noticed no difference or degradation in sound quality with either adapter or extender. Personally I don’t think it makes an audible difference unless theres a bad connection in the connector (defective).

Um, that's a gorgeous Crack. Are those 90degree RCA jacks too? Can't quite tell from the pics. Wait, on closer inspection, do you have two 90degree jacks connected together to run RCA cable down the back?! Love it.

I got a lot of questions about this build. But most pressing: how tall is that frame? You store beer kegs under the top plate?

 

[mformoriarty]

I don’t think wear is a concern, but I prefer the 90 degree connectors mostly for aesthetics… but they are also slightly easier to unplug since the top plate relies on gravity and can lift up. Not an issue when leaving a right angle adapter plugged in.

Two options:

1. Right angle male to female connector - I have this one and had good results: https://a.co/d/cT3VYpD
2. Right angle pig tail extender. This gives you a little more slack and also can use higher quality connectors. I got this one from a cable maker on Etsy I had a really awesome experience working with them, you can customize the cable length to whatever would work best for your setup. This example is TRS to XLR but I’m sure they could do TRS Male (right angle) to TRS female (straight) if you asked them. Mine was a custom request and since then they’ve added it to their whole page as a regular product: https://www.etsy.com/listing/1009811690/

Here’s what the first adapter looks like with my BHC:


And here’s the second “pigtail extender” option on my BHC - I also went with right angle RCA and a right angle power cord:




edit: I should mention I noticed no difference or degradation in sound quality with either adapter or extender. Personally I don’t think it makes an audible difference unless theres a bad connection in the connector (defective).

Woah, I need more details on that double tube adapter for the front 12AU7, looks really cool. Is your unit still stock or upgraded with speedball + other mods? Mine is still stock, planning on the speedball upgrade soon. Currently running the 6sn7 from Apos and a RCA 6as7g.

 

[raindownthunda]

Woah, I need more details on that double tube adapter for the front 12AU7, looks really cool.

12au7 to dual 6J5/6C5/L63 made by @Deyan. Equivalent to a single 6SN7. Check the 6J5 thread on head-fi. My favorite tube rolling has been with that family of tubes.

Is your unit still stock or upgraded with speedball + other mods? Mine is still stock, planning on the speedball upgrade soon. Currently running the 6sn7 from Apos and a RCA 6as7g.

Only functional mods are Speedball and Alps Blue Velvet potentiometer. I greatly enjoyed the speedball upgrade and then focused on getting into tube rolling.

Um, that's a gorgeous Crack.

Thank you!

Are those 90degree RCA jacks too? Can't quite tell from the pics. Wait, on closer inspection, do you have two 90degree jacks connected together to run RCA cable down the back?! Love it.

Yes! Two sets of 90 degree RCA connectors (CableMatters brand). This helps the cables from getting jammed against the wall behind the amp. Since my DAC is below it works out great.

I got a lot of questions about this build. But most pressing: how tall is that frame? You store beer kegs under the top plate?

Lol - it’s 4 inches tall, only 1/2” taller than stock. I wanted to show a bit more wood grain It looks taller than it is because the width and length of the case is smaller than the stock crack. I did this intentionally to reduce the “rim” between the top plate and case outer edges for a sleeker look. The full dimensions are 10 3/8” L x 6 3/8” W x 4” H. The top plate is 10x6, only 3/8” of rim.

This actually led to a major issue I didn’t anticipate - I did a test fit and none of the internals were even close to fitting!! When ordering the kit I opted out of the stock base to save a few bucks, which meant I didn’t know the minimum internal dimensions to get everything to fit. To solve this I ended up having to use a combination of CNC and chisels to get everything to fit. Thankfully I was able to borrow @TylersEclectic ’s completed BHC to figure out how big the cutouts needed to be.

Here’s an album of the full case build if you’re curious!

A few pics showing the cutouts to get internals to fit:

 

[cats4cans]

Lol - it’s 4 inches tall, only 1/2” taller than stock. I wanted to show a bit more wood grain It looks taller than it is because the width and length of the case is smaller than the stock crack. I did this intentionally to reduce the “rim” between the top plate and case outer edges for a sleeker look. The full dimensions are 10 3/8” L x 6 3/8” W x 4” H. The top plate is 10x6, only 3/8” of rim

I sometimes wonder why there aren’t more case modifications given the lengths that some people go to on other upgrades. It sure looks like space limitations can hamper or complicate some upgrades. I get that it simplifies the build and is a ready made work stand, but I really dislike connectors on the top plate. It’s one of the reasons why when I ordered a Decware speaker amp (still waiting), that I passed on the nice wooden bases in favor of the metal case with at least some of the connections on the rear panel. It seems inevitable that I’ll just have to build one for myself someday. I’m not sure of all the details yet, but I’ll be sure to start with a case laid out to better accommodate my most likely options. Nice to see a different example.

 

[Cowwe]

I don’t think wear is a concern, but I prefer the 90 degree connectors mostly for aesthetics… but they are also slightly easier to unplug since the top plate relies on gravity and can lift up. Not an issue when leaving a right angle adapter plugged in.

Two options:

1. Right angle male to female connector - I have this one and had good results: https://a.co/d/cT3VYpD
2. Right angle pig tail extender. This gives you a little more slack and also can use higher quality connectors. I got this one from a cable maker on Etsy I had a really awesome experience working with them, you can customize the cable length to whatever would work best for your setup. This example is TRS to XLR but I’m sure they could do TRS Male (right angle) to TRS female (straight) if you asked them. Mine was a custom request and since then they’ve added it to their whole page as a regular product: https://www.etsy.com/listing/1009811690/

Here’s what the first adapter looks like with my BHC:


And here’s the second “pigtail extender” option on my BHC - I also went with right angle RCA and a right angle power cord:




edit: I should mention I noticed no difference or degradation in sound quality with either adapter or extender. Personally I don’t think it makes an audible difference unless theres a bad connection in the connector (defective).

The first connector is exactly what I had in mind. Thanks, I'm off to finding one in the EU now.
Your kit looks gorgeous by the way!

 

[bagwell359]

I had actually thought about just saying "whatever, let's try to solder the speedball on and see if that fixes it" but stopped since it didn't sound like the brightest idea lol.
Either way, I have yet to decide if I want to install the speedball, since I've heard mixed opinions about the changes it brings.

I like it, but I prefer hybrids over full tubes for the most part. In this case, the speedball gives more transparency, more controlled bass. As I found later, it also allowed use of a tube that stock won't - E80CC which has more dynamics/definition than the typical array of tube types - even fancy NOS versions - in my experience.