[Benny-x]

These are the impedance values I have been gathering for headphones settings...
I picked alot of planar headphones as they are same impedance with respect to frequency.
I need to round out to only FIVE settings for my switch...

Headphones:

LCD X = 20ohm
LCD XC = 20ohm
Ether = 22 ohm
HEX = 25ohm
Oppo PM3 = 26ohm

LCD EL8 = 30ohm
HE-5 =31ohm
Code-X = 31ohm
Beyer t51i = 32ohm
Grado (most) = 32ohm
Oppo PM1 = 32ohm
Oppo PM2 = 33ohm
HE1K = 35ohm
He400i =35ohm
HE560 =38ohm
HE5LE = 38, 41ohm

HE560 = 45ohm
T50rp = 50ohm
HE6 = 50ohm
LCD2 = 47,50,60,70 ohm (!)
AKG k701= 62ohm

LCD4 = 100ohm
LCD3 = 110ohm
AKG K1000 = 120ohm

DT880 =250ohm
DT990 = 250ohm
T770 = 250ohm
T90 = 250ohm

HD600 = 300ohm
HD650 = 300ohm
HD800 = 300ohm


T1 = 600 ohm

 
+ Pioneer SE Master1 @ 45ohms
+ JVC HP-DX1000 @ 64 ohms
 
I also see that the thread is coming right along. Hopefully in a year's time when I've got the means and time to handle this you guys will have a pretty sound "formula" for upgrades. 
 
@Redge78
Your mods are looking amazing. I'm sure once you've more or less finalized what's happening to your amp you'll work on the case and make it den worthy. I love the gigantic caps you've got in there. The only other place I've seen ones physically that big were in '70s - mid-'80s giant amps and receivers from Japan. I'm a fan of them too, haha.
As for those white place "rings", they're called "zip ties" or sometimes "cable fasteners", but I think the second one is too limiting since those things are perfect for pretty much anything!
 
You guys keep up the good work, and @baronbeehive good job with getting your mods started. Titling your posts will help me follow them later on when I get this project started myself. In retrospect, minus the first post that Maxx and Redge keep updating, it'd have been good if they followed the same approach. It makes finding the posts and following the immediate ensuing discussion around the mods really easy. All of you guys should number the posts as well, so they come up in "steps" that can be followed.  

 

[Redge78]

These are the impedance values I have been gathering for headphones settings...
I picked alot of planar headphones as they are same impedance with respect to frequency.
I need to round out to only FIVE settings for my switch...

Headphones:

LCD4 = 100ohm
LCD3 = 110ohm
AKG K1000 = 120ohm
 

 
Great list ! Exactly the kind of thing we need.
 
If I remember well, the original LCD3 is 22ohm, the LCD3-Fazor is 110ohms.
When I wanted to upgrade from my HD650, I had a close look at the HD800 and the LCD3f, both being "impedance adaptation compatible" with the MK8.

 

[baronbeehive]

  ..........
 
You guys keep up the good work, and @baronbeehive good job with getting your mods started. Titling your posts will help me follow them later on when I get this project started myself. In retrospect, minus the first post that Maxx and Redge keep updating, it'd have been good if they followed the same approach. It makes finding the posts and following the immediate ensuing discussion around the mods really easy. All of you guys should number the posts as well, so they come up in "steps" that can be followed.

 
We will. Nice to have another convert along for the ride! By the time you get yours started we ........may......... have ironed out the problems, and I may have finished mine

.
 
I'm hoping to follow the tradition started by the others in providing some helpful info, as you probably know from the other LD thread I'm a complete beginner at this so it should give hope to others! If you want to see what the others have done look at page 23 & 43 for MisterX and page 33-38 for Mogos' main work, most of the pics are there before and after.

 

[Maxx134]

Just look at my pics and you'll see where I put mine. Remember that they need to sit flush against the board (no solder points in between). They are a little taller than the PCB standoffs so you can use washers if you want, otherwise you need to be careful not to over tighten the screws when you put it back together.

Thanks, I'll check it out :happy_face1: . Did you have trouble avoiding the posts? I know you said you never wanted to remove the PCB ever again :eek: .

Yes, if I can avoid removing it again I will. It's just a pain to remove it, especially now with all the extra caps on. I have removed two standoffs, one on each side by the driver tubes for easier installation.

The problem I see with removing those tiny metal "standoffs" is that they keep the board steady when you are pulling and pushing in tubes..

So be careful about the board flex without the "standoff" in place.

Since I use tube socket savers, I hold them down in place while I pry up the tubes.

But pushing in, you can't avoid, so be careful pushing tubes in..

 

[Maxx134]

The status on the next mod is:
1- Most data is complete.
2- Two members on board to help in test phase (MisterX & Mogos)
3-ordered parts wait time

Thanks aging to MisterX for the front plate idea on the switch.

Basically, we will be swapping out the single ended pug for a switch,
For the impedance selector.

For those that want to keep the single ended jack,
They make plugs that are combination single ended and XLR.
Yet I don't like plastic looking items..
Now if they made crystal. .

 

[baronbeehive]

The problem I see with removing those tiny metal "standoffs" is that they keep the board steady when you are pulling and pushing in tubes..

So be careful about the board flex without the "standoff" in place.

Since I use tube socket savers, I hold them down in place while I pry up the tubes.

But pushing in, you can't avoid, so be careful pushing tubes in..

 
I  haven't got as far as investigating that yet but would it be possible to stick a post on to the back of the board so that when it was back in it made contact with the top of the chassis to provide some stability? It may be a cause of vibration though.
 

The status on the next mod is:
1- Most data is complete.
2- Two members on board to help in test phase (MisterX & Mogos)
3-ordered parts wait time

Thanks aging to MisterX for the front plate idea on the switch.

Basically, we will be swapping out the single ended pug for a switch,
For the impedance selector.

For those that want to keep the single ended jack,
They make plugs that are combination single ended and XLR.
Yet I don't like plastic looking items..
Now if they made crystal. .

 
............he he........

. Looking forward to your results.

 

[Mogos]

   
I  haven't got as far as investigating that yet but would it be possible to stick a post on to the back of the board so that when it was back in it made contact with the top of the chassis to provide some stability? It may be a cause of vibration though.
 
 
............he he........

. Looking forward to your results.

Putting the post on the other side of the board could be a good idea. You need it only to withstanding pushing forces. Pulling is secured by the socket stopper against the top plate. To make it stable you can screw it to the borad and on the other side just stick a little rubber bumper (I don't know how it shall be called in Englih). You can buy them in harware stores and they are comming in different sizes. The olny thing you have to calculate the exact distance taging in to account the rubber cussion. And It may be that in place of the contact point there is a hole for ventilator. But in this case you can install a bar for support of the post. Even if it will be on the way of flowing air it will have no significant effect for cooling. I don't have installed the posts in this places and my sockets are different type with very tight pin holders. Till noe puching the tubes cafully did not result in any problems.

 

[SonicTrance]

 

 

 

Just look at my pics and you'll see where I put mine. Remember that they need to sit flush against the board (no solder points in between). They are a little taller than the PCB standoffs so you can use washers if you want, otherwise you need to be careful not to over tighten the screws when you put it back together.

Thanks, I'll check it out

. Did you have trouble avoiding the posts? I know you said you never wanted to remove the PCB ever again

.

Yes, if I can avoid removing it again I will. It's just a pain to remove it, especially now with all the extra caps on. I have removed two standoffs, one on each side by the driver tubes for easier installation.

The problem I see with removing those tiny metal "standoffs" is that they keep the board steady when you are pulling and pushing in tubes..

So be careful about the board flex without the "standoff" in place.

Since I use tube socket savers, I hold them down in place while I pry up the tubes.

But pushing in, you can't avoid, so be careful pushing tubes in..

I do the same thing, using socket savers. The board is plenty stable though even without the two removed standoffs. It's such a tight fit to get the sockets through the holes on top of the case, so when they "snap in" it's very stable.

 

[SonicTrance]

So, are you guys ready for some viking rock? Swedish Sabaton!
Don't expect any of you to like it but I do,haha! 

 
 

 

[Maxx134]

@mogos,
Rubber bumper , maybe "hotglue" onto board is a dam excellent idea!
In fact, it would even be optimal to have more around board as long as not inhibit air flow..

 

[baronbeehive]

  So, are you guys ready for some viking rock? Swedish Sabaton!
Don't expect any of you to like it but I do,haha! 

 
......

 
Is that the Swedish entry for Eurovision then

. Reminds me a bit of Epica or Rammstein. Perhaps we should include a music spot on this thread!!

 

[Mogos]

@mogos,
Rubber bumper , maybe "hotglue" onto board is a dam excellent idea!
In fact, it would even be optimal to have more around board as long as not inhibit air flow..

But we have to remeber that the hot glue gets stiff as it cools down. Or maybe there are some kind which maintain elasticity. Ok now I get it you want to put some extra ones with hot glue. It wil be for certain good for the board stability. But any way to obtain good support and contact of the post to the plate it will be good to put some rubber material on one end.

 

[SonicTrance]

 

  So, are you guys ready for some viking rock? Swedish Sabaton!
Don't expect any of you to like it but I do,haha! 

 
......

 
Is that the Swedish entry for Eurovision then

. Reminds me a bit of Epica or Rammstein. Perhaps we should include a music spot on this thread!!

Haha! No Eurovision for Sabaton I think

 

[baronbeehive]

  Haha! No Eurovision for Sabaton I think

 
Why not? I seem to remember Norway had a very heavy metal band one year. Seriously I still love Abba, to me on a par with the Beatles.

 

[Maxx134]

I will soon be testing my third set of WCF caps,
on my quest on fine tunning the amp...

Based on these results, they will either verify or not,
my conclusions based on the two previous caps.

Third set will rule out chance in my observations.
Then I will have new cap recommendations for this position.