The new "My Ref" Rev C thread - Page 66 - diyAudio
Go Back   Home > Forums > Amplifiers > Chip Amps

Chip Amps Amplifiers based on integrated circuits

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 3rd May 2009, 03:21 AM   #651
diyAudio Member
 
Join Date: Aug 2008
Quote:
Originally posted by ClaveFremen


Click the image to open in full size.

They're regular SIL socket strip, I've bought mine from RS Components (267-7400), in US you could find them from Mouser:

506-510-AG90D (This code is pretty similar)

Others from this search

Dario

If I'm using this socket to C13 position for ease output cap swamping do you think it would effecting the the quality of the output...I have few to try out....
  Reply With Quote
Old 3rd May 2009, 08:59 AM   #652
Reality first!
diyAudio Member
 
ClaveFremen's Avatar
 
Join Date: May 2005
Location: Milan, Italy
Hi Gabanyayaya,

my MyRef sounds very good with a LOT of sockets.

For sure solder joints are better but for testing I can't hear any difference.

Since some caps (Silmics for instance) would not fit directly in those sockets, I've trimmed caps legs with a nail file.

Good testing!
__________________
Dario
ClaveFremen "Bailando Salsa en el Sietch"
  Reply With Quote
Old 3rd May 2009, 09:42 AM   #653
diyAudio Member
 
Join Date: Aug 2008
Quote:
Originally posted by ClaveFremen
Hi Gabanyayaya,

my MyRef sounds very good with a LOT of sockets.

For sure solder joints are better but for testing I can't hear any difference.

Since some caps (Silmics for instance) would not fit directly in those sockets, I've trimmed caps legs with a nail file.

Good testing!

Dario,

Thanks....certainly i will do this to the Obbligator that i have now...i learn my lesson today when removing C32 to replace it with Wima. Too much desoldering might ruin the only MyRef C board that i have....thanks!
  Reply With Quote
Old 3rd May 2009, 12:38 PM   #654
Reality first!
diyAudio Member
 
ClaveFremen's Avatar
 
Join Date: May 2005
Location: Milan, Italy
Quote:
Originally posted by ClaveFremen
C30 Wima FKP2 1nF 63V
C21 Wima FKP2 22nF 63V (to be mounted in the bottom side of PCB)
C4, C5 Wima MKP4 100nF 250V 7.5 mm lead spacing
C7 Wima MKP2/MKS2 100nF-220nF 63V
C32 Wima FKP2 150 pF 100V
C13 Mundorf MCap 1.0uF 250V (low cost, perfect fit)
C13 Mundorf MCap Zn 1.2uF 250V (best but outboard)

C13 has to be bypassed by a 10 nF Wima FKP2
C30 must be read as FKP2 1nF 100V (mines are 100V)

For those that want to try the baseline mod here it is the Mouser BOM for the Import Tool:

505-MKS2.22/100/10|2
505-MKP4.1/250/10|4
505-FKP21000/100/5|2
505-FKP20.022/63/2.5|2
505-FKP2150/100/2.5|2
505-FKP20.01/63/5|2

In Europe alternate sources are Banzai Effects and RS Components.
Attached Images
File Type: jpg capsupgrade.jpg (76.0 KB, 883 views)
__________________
Dario
ClaveFremen "Bailando Salsa en el Sietch"
  Reply With Quote
Old 3rd May 2009, 07:42 PM   #655
troystg is offline troystg  United States
diyAudio Member
 
troystg's Avatar
 
Join Date: Apr 2004
Location: In a dream... Please don't wake me.
Quote:
Originally posted by ClaveFremen


C30 must be read as FKP2 1nF 100V (mines are 100V)

For those that want to try the baseline mod here it is the Mouser BOM for the Import Tool:

505-MKS2.22/100/10|2
505-MKP4.1/250/10|4
505-FKP21000/100/5|2
505-FKP20.022/63/2.5|2
505-FKP2150/100/2.5|2
505-FKP20.01/63/5|2

In Europe alternate sources are Banzai Effects and RS Components.

Excelent information..

I will swap out those components on the made kit when I assemble my other set of PCB's with the upgrades.

Right now I am making 3 sets of 41Htz AMP 32 PCB's.. WAY more difficult to assemble those SMB components than these hole throughs. A total PITA!!

I can't wait to go back to assembling my second Rev_C and Steve Dunlaps' Krill.
__________________
Troy
Thinking positive doesn't make things better, it makes you a better person.
  Reply With Quote
Old 3rd May 2009, 11:17 PM   #656
Bengali is offline Bengali  United States
diyAudio Member
 
Join Date: Oct 2006
Quote:
I did some search, and it seems that these have 6 Ohm impedance, and are not very effecient. Wonder if the transformer is not big enough.
Hi soongsc,

actually MMG's are 4 ohm impedance. that's why I chose 20V 200VA transformer instead of higher one.

aside from that, I don't need to turn it up very loud.

I use a mini-Aleph with the MMG's. the mini-A is only about 10W per channel. Sound is incredible, very smooth and wide sound stage. I can listen for hours and use it for movies as well.

I was hoping my ref C can produce similiar sound so I can build 5 channel version. It could very well be MMG's just not a match for the my ref C.


thanks.
  Reply With Quote
Old 4th May 2009, 12:01 PM   #657
soongsc is offline soongsc  Taiwan
diyAudio Member
 
soongsc's Avatar
 
Join Date: Mar 2005
Location: Taiwan
Quote:
Originally posted by Bengali


Hi soongsc,

actually MMG's are 4 ohm impedance. that's why I chose 20V 200VA transformer instead of higher one.

aside from that, I don't need to turn it up very loud.

I use a mini-Aleph with the MMG's. the mini-A is only about 10W per channel. Sound is incredible, very smooth and wide sound stage. I can listen for hours and use it for movies as well.

I was hoping my ref C can produce similiar sound so I can build 5 channel version. It could very well be MMG's just not a match for the my ref C.


thanks.
Hmm, I haven't had the time to put mine together yet, but I wonder whether the current drive section is for 8Ohm. It seems that the current delivered is proportional to the input voltage. Wasn't it mentioned somewhere that some component change was necessary to drive less than 8 ohm load?
__________________
Hear the real thing!
  Reply With Quote
Old 4th May 2009, 04:20 PM   #658
Bengali is offline Bengali  United States
diyAudio Member
 
Join Date: Oct 2006
Quote:
Wasn't it mentioned somewhere that some component change was necessary to drive less than 8 ohm load?
if you have any info on parts change required for 4ohms,
please let me know.

as far as the posts I've read, only lower voltage transformer
is needed as to not exceed the 3886's max ratings.

thx
  Reply With Quote
Old 4th May 2009, 09:17 PM   #659
Reality first!
diyAudio Member
 
ClaveFremen's Avatar
 
Join Date: May 2005
Location: Milan, Italy
For those that are going to try the baseline mod I suggest to DC couple first ( Make sure there's no DC offset from the output of your pre!!!).

I'm suggesting this because C13 has a great impact on sound and characterize it masking some of the effects of the mods (the Kemet/Arcotronics included in kits is particularly bad in that sense...).

It's for this reason that I've done all my tests with a DC coupled MyRef.

Once the ampli is fully calibrated it's easier to select the most transparent C13 cap that better suits your taste.
__________________
Dario
ClaveFremen "Bailando Salsa en el Sietch"
  Reply With Quote
Old 5th May 2009, 02:59 AM   #660
Bengali is offline Bengali  United States
diyAudio Member
 
Join Date: Oct 2006
I pulled C13 and did DC Couple. Sounds much better. I still get the sharp 'zzzz'. What did you do to get rid of this sharp highs?

I watched Phantom of the Opera in HD and turned the volume up. Sounds pretty good for a little chip amp. 2 Channel music is good
but with movies, this amp does better.

thx
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
The "What slogan would you have if you were a high-end audio company?" Thread. Spasticteapot Everything Else 118 27th September 2011 03:31 AM
Original ECL86 "Baby Huey" thread jkeny Tubes / Valves 14 23rd November 2009 07:35 PM
"compact loudspeaker factory visit from "magico mini" thread Nanook Multi-Way 2 4th January 2008 07:30 AM
The "Really simple and cheap speaker designs for the newbie!" thread. Spasticteapot Multi-Way 5 19th March 2006 04:16 AM


New To Site? Need Help?

All times are GMT. The time now is 07:02 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2