rebuild

[luczamic]

Hi guys,

I really hate being a pain. 
I think I must've done some mistakes during the build as I don't really like the sound. I tried with the speedball and without. For me, the sound is kind of muffled and without separation. I thought that it's maybe just the way the HD6xx are, but I got a simple 5.1 Pioneer speakers amplifier at home, and the headphones sound much better with that.
And before you say, it's a tube sound, I heard tubes before and I loved them, I just never could afford a tube amp before now, and that is why I went with crack.

I read some posts that the sound issues might be caused by poor build quality i.e bad, cold solder joints, or not properly trimmed cables and I've seen some very tidy build cracks on this forum. My looks like a dog's breakfast...
I can't see any other issues than this, as my voltages are spot on, and the headphones are dead quiet, even when the volume is all the way up.

That's why I'm willing to have another go at it. I'm planning to take it all apart and try to do this again with fresh set of cables.

My question is where should I be able to get these cables from, are they some special cables? I can see markings C2118A. I'm in AU BTW

I've also uploaded some photos of the build. If you guys would be so kind and have a look at them in your spare time? Maybe you can point me to some obvious problems...

And don't get me wrong, it's not like this is unlistenable, I just can't believe that I'm the only one with this kind of issue and that I would prefer the sound of some simple 5.1 system. I just know I made a mistake somewhere. Crack must sound better.

Any help will be much appreciated.

Thanks!
Michal

[AB2KH]

Michal,
Cheque the value of the 12AU7 plate load resistors, from the colour bands in your photo they look to be the wrong values.

Chris/AB2KH

[Thermioniclife]

Those resistors are 22k they call for 22.1k.
100 ohms one way or the other is probably fine.

[Paul Birkeland]

the sound is kind of muffled and without separation.

This is what I would expect from problematic solder joints.  When building a kit, it's important to attach wires and components to the terminals before soldering so you have a mechanical connection at work before the solder is applied.  If you just slip a wire through a hole and solder over it, then you are often relying too much on the solder itself to do the job, and these problematic connections will loosen up over time. 

As an example, the wire going into A7 is a decent example of what we don't want, while the wire going into B3 is bent up vertically and sits against the terminal, then solder has been flowed all the way over that, which is great. 

If both channels are muffled, chances are you have a soldering problem along the path the black wires make from your RCA jacks back into your power supply.

[luczamic]

Thanks, Guys for your insight.

I will definitely be more careful in making sure that the connections are properly sitting on the terminals before soldering them on.

In regards to the resistors, yes when I was upgrading crack with speedball I've cut the installed resistors instead of desoldering them, and I couldn't use them when downgrading to stock. Lesson learned.
These were the closest ones I could find in AU. Will this have an impact?

Also, can you see anything wrong with speedball plates? I wasn't planning on redoing them, I figured that maybe I didn't like the speedball upgrade because of the issues I have with the stock crack not sounding right.

If both channels are muffled, chances are you have a soldering problem along the path the black wires make from your RCA jacks back into your power supply.

I will definitely have a look at that, Thanks PB

Thanks guys.

[AB2KH]

Michal,

Are the two lugs on the volume pot where the black wires are connected tied together ( top and bottom )?

Chris/AB2KH

[luczamic]

Hi Chris, thank for the reply,

Yes it appears they are (see photos)

Thanks!

[Paul Birkeland]

That's the HP jack, not the volume pot.

The 2.49K resistor that meets the white wire is not captured by solder.

[luczamic]

Ohh, God!! thanks, PB, moments like this make me think that I'm lucky that I even managed to build this thing without killing myself    

I've also uploaded some better-quality photos so it's easier to see the mess.

PB, is there anything you could see obviously wrong with the Speedball plates? Thanks

[Paul Birkeland]

I saw at least one solder joint on your large Speedball board that hadn't flowed through the board. 

If you have muffled weird sound from the stock build, you'd want to address that before listening to the Speedball, as a cold solder joint will cause sonic problems in either version of the amp.

[luczamic]

Thanks guys, for all you help and tips
I’ll try to order the wires and go get miles of desoldering wire 😂

Wish me luck!