Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Headphone Systems Everything to do with Headphones

QRV04 Headphone Amp. + Red Baron v5 DAC
QRV04 Headphone Amp. + Red Baron v5 DAC
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
Thread Tools Search this Thread
Old 12th November 2015, 10:56 AM   #1
savinalexandru is offline savinalexandru  Romania
diyAudio Member
Join Date: Jun 2006
Default QRV04 Headphone Amp. + Red Baron v5 DAC

Hi everyone,

I would gladly listen of your opinions regarding conecting this two pieces of DIY as i try to figure best solution.

1. Active or passive I/V stage before conecting to qrv?
2. Conecting to qrv directly to Tda1542 pin is possible?
3. Input caps on qrv does influence sound greatly, so i could remove the smd type and put some Mundorf for example?
4.removing completly the input caps on the qrv and put sowther transformers between dac and the headphone amp.?

Ps: sennheiser hd600 listening cans.

Thanks in advance for your help!
  Reply With Quote
Old 12th November 2015, 12:07 PM   #2
sgrossklass is offline sgrossklass  Germany
diyAudio Member
Join Date: Nov 2004
Location: Germany
That DAC has the usual DAC-related tinkerer-level audiophile snake oil pretty well covered, save for exotic capacitors. I am not denying that passive I/V can be useful, but that's just because you didn't put in enough filtering effort to get rid of all the high-frequency crap coming out of the converter beforehand. That sort of stuff tends to irritate bipolar input opamps in particular, a reasonably fast-slewing FET input parts tends to be beneficial.

You know, most people would probably prefer a DAC that actually works properly. Like, say, a decent onboard audio output. Or an ODAC if you want a higher level of performance and USB is your thing. Or whatever (some sort of decent PCM5102A based job maybe). DACs are mostly a solved problem though I guess some people still prefer shooting themselves in the foot.

The QRV04 is good. It allows you to experiment with some output series resistance (for a somewhat fuller bottom end on HD600s, try values of like 2x 100 ohm to 2x 200 ohm, giving 50-100 ohms). Be sure to populate the input filter components. As for the input coupling caps, I'm sure Per-Anders doesn't specify any crap-quality components, plus you could still generously oversize things even if you were forced to use MLCC ceramics. If your DAC output is AC-coupled, you could even replace them with simple wire links / 0-ohm resistors. I would never use any of these ridiculously huge Mundorf speaker crossover film caps in such a place, just some decent WIMAs or Panasonics.

I see the power supply does not use capacitors from the regulators' ADJ pins to ground. Those may be worth adding, like 10 F (25+V) electrolytic. It shouldn't matter much in terms of noise, but regulation / transient behavior should improve.
  Reply With Quote
Old 12th November 2015, 07:04 PM   #3
savinalexandru is offline savinalexandru  Romania
diyAudio Member
Join Date: Jun 2006
10x a lot for great info.

I will try to get that smd Evox Riva caps that P-A is recommending. (although is hard to find them)

Second, you're probably(sure) right, but my pleasure to tinker and plant all components on a pcb is greater than buying a fully built dac.

BTW, you're right i'm going to use USB. WaveIO seems a good choice?

About supply, all powered by shunt regulators. It's going to be a big box....and a LOT of tinkering!

  Reply With Quote


QRV04 Headphone Amp. + Red Baron v5 DACHide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
FS LL1694 , Red Baron V5 tube Izar Myint67 Swap Meet 6 14th May 2015 01:13 AM
Red Baron TDA1541 monster dtses Swap Meet 3 31st January 2015 05:04 PM
DAC/Headphone Amp Peter Menting Swap Meet 3 9th June 2014 02:21 PM
FS..Red Baron Dac V4 beardman Swap Meet 3 31st October 2013 10:22 AM
Red Wine Audio Dac/Amp lpd Swap Meet 3 28th February 2013 09:11 PM

New To Site? Need Help?

All times are GMT. The time now is 12:59 AM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright ©1999-2019 diyAudio