My_Ref Fremen Edition - Build thread and tutorial - Page 43 - 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 21st June 2013, 02:21 PM   #421
diyAudio Member
 
voxxonline's Avatar
 
Join Date: Aug 2012
Location: Bexleyheath, Kent
Send a message via Skype™ to voxxonline
Ok
__________________
How to find time to finish my projects ?
  Reply With Quote
Old 22nd June 2013, 07:17 PM   #422
diyAudio Member
 
fromthecrowd's Avatar
 
Join Date: Jan 2013
Default Additional headphone output

Is it permitted/acceptable to add a headphone output to My_Ref FE? Something like the one on the attached sheme. Note that the Out_Gnd lines of right and left blocks have to be joined for this. Comments highly appreciated!
Attached Images
File Type: png head.png (8.8 KB, 157 views)
  Reply With Quote
Old 22nd June 2013, 07:27 PM   #423
diyAudio Member
 
voxxonline's Avatar
 
Join Date: Aug 2012
Location: Bexleyheath, Kent
Send a message via Skype™ to voxxonline
I don't know the answer, but may I ask how is the sound ?
__________________
How to find time to finish my projects ?
  Reply With Quote
Old 22nd June 2013, 08:14 PM   #424
diyAudio Member
 
fromthecrowd's Avatar
 
Join Date: Jan 2013
The amplifier is not assembled yet, so its early to make objective judgements. But, ofcourse I listened to it a lot in its scattered state and with cheap pots and with preliminary wiring. Computer with O-DAC was mainly used as a source. May be the O-DAC is not top of the class, but it certainly is far better than FM tuner. Music was Mozart violin and piano concertos, Terauchi electric guitar, Weber rock opera JC Superstar. First of all bass on the speakers had to be lowered (they feature regulated crossover). Because the bass is very strongly expressed. After that the sound became pleasant and detailed. It has the property of being not fatiguing on a long term. I heard these AR10pi speakers driven by a couple of my fathers Marantz amps (the 80s models, don't remember which) and lately by a LM1875 chipamp (not bad). Compared to those My_Ref FE is distinctly better. Music appears well balanced and articulated. That is, instruments are not obscured one by the other. Merely by refocusing attention one can distinguish the particular line. The challenging string instruments are very authentic. I look forward to examine the sound of egyptian horns in the Aida with this amplifier. Never heard them properly reproduced. These are my impressions for the moment. A lot more listening is planned and I will continue to share my impressions.
  Reply With Quote
Old 22nd June 2013, 08:55 PM   #425
Reality first!
diyAudio Member
 
ClaveFremen's Avatar
 
Join Date: May 2005
Location: Milan, Italy
Quote:
Originally Posted by fromthecrowd View Post
Is it permitted/acceptable to add a headphone output to My_Ref FE? Something like the one on the attached sheme. Note that the Out_Gnd lines of right and left blocks have to be joined for this. Comments highly appreciated!
Sorry, I don't know...

Quote:
Originally Posted by fromthecrowd View Post
First of all bass on the speakers had to be lowered (they feature regulated crossover). Because the bass is very strongly expressed.
Interesting...

If this is a problem it can be addressed changing C13.

A NOS K71-4 (which is a bit bass shy but really refined) may bettter suit you needs.

The MP915s on the regulator have a big role in bass response, you can swap them with metalfilm resistors to lower it if C13 swap it's not enough.

Quote:
Originally Posted by fromthecrowd View Post
After that the sound became pleasant and detailed. It has the property of being not fatiguing on a long term.


Quote:
Originally Posted by fromthecrowd View Post
A lot more listening is planned and I will continue to share my impressions.
Thanks for sharing, I'll read with interest next posts.
__________________
Dario
ClaveFremen "Bailando Salsa en el Sietch"
  Reply With Quote
Old 22nd June 2013, 09:35 PM   #426
diyAudio Member
 
fromthecrowd's Avatar
 
Join Date: Jan 2013
Dario, thanks for valuable advice! Plans are to mount the scattered parts to an open chassis, and after that to start tuning. Regarding the bass issue, old AR speakers may be responsible for that. Large drivers had torn rubber replaced few years ago. And, the drivers being not one of the standard sizes, the repair went not without compromises. They may reproduce deep bass not very well (for instance, contrabass in Mozart's 3rd violin concerto). At the lower bass settings of crossover they work nicely with My_Ref now. Also the source may not have been perfect. I will listen for some time and try variants of C13.
  Reply With Quote
Old 22nd June 2013, 11:56 PM   #427
diyAudio Member
 
lehmanhill's Avatar
 
Join Date: Jan 2008
Location: Chelsea, Michigan
Quote:
Originally Posted by fromthecrowd View Post
Is it permitted/acceptable to add a headphone output to My_Ref FE? Something like the one on the attached sheme. Note that the Out_Gnd lines of right and left blocks have to be joined for this. Comments highly appreciated!
I'm sorry to say that, just like Dario, I don't know the answer. I suspect that you might give up some sound quality or hum on the headphone side because you may be introducing a potential ground loop by combining the grounds. If you keep the switches and headphone components close to the audio ground from your source, it might be OK.

I don't think you would hurt the amps by trying it. Why not just try it as an experiment before building the enclosure? We would love to hear about it.
  Reply With Quote
Old 23rd June 2013, 12:15 AM   #428
bcmbob is offline bcmbob  United States
diyAudio Member
 
Join Date: Dec 2009
Location: Bay City, Michigan
I had several AR speakers "back in the day" and they were all acoustic suspension. I'm assuming if yours are some of those great classics - yours are also. Though considered the "Cadillac" of sound production by many, as I remember their best reviews had to do with clarity over coloration. The last few speakers I've built are all bass reflex, as driver technology for controlling cone movement has really improved. My preference has kept me there and I'm not claiming it to be a top choice for everyone.

I'm simply suggesting if you don't own any, try to find a pair of good quality BRs somewhere in your auditions. I suspect much of the mid warmth the FEs are capable of might be masked by the "clean" nature of acoustic suspension cabinets. Just Sayin.....
__________________
Bob M.
"Arrange Whatever Pieces Come Your Way."
  Reply With Quote
Old 23rd June 2013, 04:32 AM   #429
diyAudio Member
 
fromthecrowd's Avatar
 
Join Date: Jan 2013
Quote:
Originally Posted by lehmanhill View Post
Why not just try it as an experiment before building the enclosure? We would love to hear about it.
Yes, I'll do it in the coming week and report. Thank you.

Quote:
Originally Posted by bcmbob View Post
I'm simply suggesting if you don't own any, try to find a pair of good quality BRs somewhere in your auditions. I suspect much of the mid warmth the FEs are capable of might be masked by the "clean" nature of acoustic suspension cabinets. Just Sayin.....
I appreciate and will follow your advice.
  Reply With Quote
Old 23rd June 2013, 02:00 PM   #430
diyAudio Member
 
voxxonline's Avatar
 
Join Date: Aug 2012
Location: Bexleyheath, Kent
Send a message via Skype™ to voxxonline
Allright.
I have tested one channel.
It is only one speaker but simple thing- soundstage from monophonic sound was already promising.
All and every detail of the music qualitative evaluation was 10 light years ahead of the amp I have now.
Will wait for another board to be done and will give my impressions then.
I can imagine break in of all parts is going to take place so sound should get better after that also.
Bass is good. 3D sound and separation of instruments great.
The only thing - I must be liking more rolled off high end than I have now- but it is the domain of k71-4 cap in b1 (together with nichicon electrolytic which adds some highs on top). Because I am changing to another passive pre with buffered dac - things will improve.
Plus, again- break in...
And yes- this amp is unforgiving to bad mastering and SQ.

Sincerely yours
Ivan
__________________
How to find time to finish my projects ?
  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
My_Ref Fremen Edition RC - Build thread ClaveFremen Chip Amps 1239 12th May 2014 06:09 PM
My_Ref Fremen Edition - Beta build/Fine tuning ClaveFremen Chip Amps 1523 1st December 2013 11:16 AM
My_Ref Fremen Edition - need help on PCB evaluation ClaveFremen Chip Amps 450 23rd October 2013 03:38 PM
My_Ref Fremen Edition Interest/Group Buy ClaveFremen Group Buys 348 25th June 2013 09:58 PM
Last My_Ref Fremen Edition RC boards for sale ClaveFremen Swap Meet 3 4th December 2012 01:04 PM


New To Site? Need Help?

All times are GMT. The time now is 07:37 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