How many VA are sufficient for the Placid Power Supplies? - diyAudio
Go Back   Home > Forums > Commercial Sector > Manufacturers > Twisted Pear

Twisted Pear Superior quality electronic kits

Reply
 
Thread Tools Search this Thread
Old 20th May 2014, 08:32 PM   #1
Salar is offline Salar  Germany
diyAudio Member
 
Join Date: Feb 2006
Location: Germany
Default How many VA are sufficient for the Placid Power Supplies?

I know, the answer must be hidden in the threads, but search did not help.
So for any newbie building a Buffalo DAC with IVY who wants to look up the minimum ratings:

The transformers for the Placid Power supplies are rated

2x9V / 30VA

2x15V / 50VA.

But there is a lot of headroom.

What is the minimum VA one needs for driving a single and a bipolar Placid?

All the best,
Salar
  Reply With Quote
Old 23rd May 2014, 06:44 PM   #2
diyAudio Member
 
Join Date: Mar 2011
The minimum rating is what you already have mention. Not long ago tpa went up from 15va on the 9v and 30va on the 15v trafo's. ( I am using 200va trafo's.)

Don't destroy the great sound from a Buffalo dac by using to small trafo's.
  Reply With Quote
Old 23rd May 2014, 09:32 PM   #3
diyAudio Member
 
Join Date: Jun 2012
Salar - i recently built Buffalo 3 with Legato 3.1 using standard 30VA Traffos (from on TPA site, though there's no longer 30VA option for 15V)

smooth dancer - Could you please describe the changes in sound when going from standard traffos to big ones? I built Buffalo 3 recently and due to shipping cost ordered only 30VA traffos, but now i think of jumping to something like 100VA for Legato (i guess 30va should still be enough for dac part?).
I already feel like sound could use more dynamics and attack compared to my older 4397 based dac with discrete output. Although there's a lot of stuff that makes me happy - the cleanness, precision, no "sharp edges" or digital grain. Maybe bigger traffo and increasing voltage to 15V should add that little bit of dynamics and attack i'm missing.
  Reply With Quote
Old 23rd May 2014, 11:23 PM   #4
diyAudio Member
 
Join Date: Mar 2011
With bigger trafo's you will get what you miss now. Better dynamics and contol. BUT the best to do is to buy the new Placids ( when they hopefully soon will be available ). A huge step forward in my system.
  Reply With Quote
Old 23rd May 2014, 11:42 PM   #5
diyAudio Member
 
Join Date: Jun 2012
Oh, that's good to hear - getting bigger traffo is not too difficult time and money wise and i was going to order new Placids anyway once they are availible.
Is it worth getting both new placids, or BP only? I thought dac side should be pretty happy about it's power already...
  Reply With Quote
Old 23rd May 2014, 11:49 PM   #6
diyAudio Member
 
Join Date: Mar 2011
Change all Placids. BP and HD.
  Reply With Quote
Old 30th May 2014, 06:24 PM   #7
Salar is offline Salar  Germany
diyAudio Member
 
Join Date: Feb 2006
Location: Germany
Hello to all,
thanks for the replies.
Maybe Ill have to be a little more specific:
I will build an amp, with Buffalo and IVY and the needed Placids, all stuffed in one cabinet,
using a custom made toroid transformer with 6 secondaries.

The cabinet for all the components and pcb is very, very tight.
It took me two days just to shuffle around drawings of the pcbs to make everything fit and ensure heat dissipation.
So every mm is needed and there is literally no space to waste for any additional copper windings or VA that do not make sense.
In the moment a transformer with 300VA for the amp alone plus 30VA and 50VA secondaries would be too big.
(BTW, we are talking about 30/50 total, for both secondaries?)

There might be some headroom in my design, but as a start
a statement about the minimum VA for the current Placids would be very helpful.

Last edited by Salar; 30th May 2014 at 06:36 PM.
  Reply With Quote
Old 30th May 2014, 08:37 PM   #8
diyAudio Member
 
Join Date: Mar 2011
Why so small cabinet ? It just complicate things. I guess you want to get the best sound out of your dac ?

I ended up with two cabinets. One for the trafo's and Placid BP's, and the other one for two BIIIse in dual mono.( with Placid HD's and Ivy's.)

Big enough trafo's is a must to get max out of the Buffalo dac.

( Sry for not give an answer to your question )
  Reply With Quote
Old 30th May 2014, 09:14 PM   #9
diyAudio Member
 
Join Date: Jun 2012
The answer is easy then - the smallest traffo Twisted Pear offered previously was 30VA, now they only offer 50VA for BP, so I guess 50VA is optimum but since 30VA worked - it's minimum. At least I use it with 30VA for now and it work, although like I said earlier - I feel like It could use a bit more dynamics\attack and I expect to get that with new 100VA trafo and new Placids.
I'll report back when I triy 100VA traffo - if difference will be huge the 30VA probably won't be a good choice then...
  Reply With Quote
Old 30th May 2014, 10:24 PM   #10
Salar is offline Salar  Germany
diyAudio Member
 
Join Date: Feb 2006
Location: Germany
According to this thread @ twistepearaudio, a Placid HD BP draws about 890mA. Adding some headroom, lets say 1.5A.
In this scenario,the math says 22.5VA should be sufficient, correct?
All the best,
Sal
  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
FS Buff II DAC + Placid PSU + IVY III + Placid BP PSU - $350 ianp Swap Meet 1 23rd March 2013 03:38 AM
FS: Buffalo II DAC + Placid Combo, Legato I/V Stage, 2x Placid BP Modules damohpi Swap Meet 4 23rd November 2010 09:51 AM
+/-15V power to a TI PGA2310. 15V regulators sufficient or do I need adjustable?? nick_g_evans Parts 2 16th July 2008 12:50 PM
Transformer VA versus output power VA nigelwright7557 Solid State 8 18th May 2008 03:57 PM
Sufficient power for the Fountek JP-2.0? mazeroth Multi-Way 3 20th April 2005 04:37 AM


New To Site? Need Help?

All times are GMT. The time now is 11:24 PM.


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