Head-Fi.org › Forums › Equipment Forums › Headphone Amps (full-size) › Bottlehead Amplifier Discussion / Comparison Thread: Crack, SEX & Mainline
New Posts  All Forums:Forum Nav:

Bottlehead Amplifier Discussion / Comparison Thread: Crack, SEX & Mainline - Page 20

post #286 of 807
Thread Starter 
Quote:
Originally Posted by JamieMcC View Post
 

That's a nice blue its kind of got a touch of Tealness to it. Do you have the name for it?

It's called "The blue the guy at Riga Craft managed to create"! ;) So, no, sorry. He showed me some samples and I just said "something like that one" so that's kind of what I got.

post #287 of 807

Hi Loquah the Main line looks fantastic on the Bottlehead forum. Thinking about your pinstripe if you had some of the metallic pin stripe left over you might see if it would take a burnish.

 

 


Edited by JamieMcC - 12/5/13 at 12:22am
post #288 of 807
Thread Starter 
Quote:
Originally Posted by JamieMcC View Post
 

Hi Loquah the Main line looks fantastic on the Bottlehead forum. Thinking about your pinstripe if you had some of the metallic pin stripe left over you might see if it would take a burnish.

 

 

 

Oooh. That looks great!

post #289 of 807
Thread Starter 

Last night's session produced the power supply wiring and the various circuit board sections of the Mainline build.

 

Here's the power supply board hovering above the main power transformer:

 

 

These are the other circuit boards. 2 x C4S boards and one bias board (which I don't fully understand yet, but will explain once I install it and work out what it does!)

 

 

And 2 semi-arty shots just because... ;)

 

 

post #290 of 807
Thread Starter 

Sorry for the quick double-post. This morning I had a little time for a few more connections and wired the input stages. Bottlehead employ a Cat-5 cable for this which was quite good to work with. Any Mainline veterans looking at this may notice that I mixed up the orange and brown pairs. This was due to a trimming error and forced me to deliberately and carefully substitute brown for orange and vice versa. I also found the lengths of stripped wire at the input end (1st image below) weren't quite sufficient so I had to slide the whole Cat-5 cable further towards the inputs than the instructions said. This might have been an error on my part, but it's no big deal, just not quite as neat as it could have been.

 

Connections to the very nice quality RCA sockets. Notice the grey Cat-5 insulation extends a lot further past the cable tie than it's meant to. No biggie, but a little less "perfect" than I would have liked.

 

 

Connections to the input switch. I used a sheath of clear heat-shrink to protect the individual cores of the Cat-5 where the cable tie tightens down. Also, Bottlehead supplied white cable ties, but I had to cut them off when I realised my wire stripping lengths weren't quite right and I had to shift the cable.

 

 

A view of the full chassis with the Cat-5 running from front to back. I've also temporarily put some resistors in place (but not soldered) at the tube sockets because I was worried they might go astray. I'll talk more about that stage when I get to the correct time to install them.

 

post #291 of 807

Looks like it's shaping up nicely :)

post #292 of 807
Looks like she's coming along nicely indeed! Did you have to do anything special for grounding purposes in light of the anodizing? I recall when building my o2 that I was directed to file down part of the case around one of the screw holes for that reason.
post #293 of 807
Thread Starter 
Yes, there's a "master" earth connection near the power inlet on all BH amps. I filed back the metal around that whole on the underside of the plate. I also noticed that the friction of the screws tightening against the plate is enough to scrape away the anodized layer.
post #294 of 807

Makes sense!  I'm listening to my mainline right now so I can't flip it, but think you may want to do the same for many (all?) the various metal tabs under the standoffs, etc.  You will end up connecting drain wires to a number of them, when wiring the tube sockets for example, and at least in a stock build, they are touching the chassis/ground plane.


Edited by skeptic - 12/6/13 at 11:38pm
post #295 of 807

Every time I see your blue top plate I like it more. Nice work, and so far with the Crack under the belt the Mainline build is not looking overly intimidating (well a little bit) to this newbie with a slow and methodical approach. How does the build manual provided for the Mainline compare with the Crack and Sex is it very much along the same detailed lines? I am expecting it to be but it doesn't hurt to ask.


Edited by JamieMcC - 12/7/13 at 1:09am
post #296 of 807

The mainline build manual is excellent, true to bottlehead form.  There are a lot more connections to make than a crack + speedball but none that require any more dexterity imo.  

post #297 of 807

Loquah, good work on your trouble shooting, its been interesting to follow the process over at Bottlehead.

post #298 of 807
Thread Starter 
Quote:
Originally Posted by JamieMcC View Post
 

Loquah, good work on your trouble shooting, its been interesting to follow the process over at Bottlehead.

 

Thanks Jamie!

 

I'll discuss some of the challenges when I do the write-up over here. It's burning in now and sounding good, but it's not as far ahead of the SEX as I expected (i.e. so far the SEX seems very, very good for the price difference)

post #299 of 807
Thread Starter 

The Mainline is done!!

 

I've completed all the assembly, but now need to finish the base, burn it in and give it some solid listening time before I comment in detail and review it.

 

Early impressions are that it's a serious piece of kit that has buckets of power, but is very polite and smooth without losing any detail. I particularly like the balanced output option and the attenuator setup - really nice!!

post #300 of 807
Looking forward to your mainline comments. Keep up the great work!
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Headphone Amps (full-size)
Head-Fi.org › Forums › Equipment Forums › Headphone Amps (full-size) › Bottlehead Amplifier Discussion / Comparison Thread: Crack, SEX & Mainline