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

Vendor's Bazaar Commercial Vendors large & small hawking their wares

Universal Buffer achieving -140 dBc (0.00001 %) THD
Universal Buffer achieving -140 dBc (0.00001 %) THD
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 18th January 2020, 01:33 AM   #111
aive is offline aive  Australia
diyAudio Member
 
Join Date: Sep 2013
Quote:
Originally Posted by tomchr View Post
one of the guys there got me into a recreational hockey league for folks in the electronics industry.
Wow that sounds super niche sporting! :P

Great looking product - keen to get one to convert balanced output from existing preamp to SE for input into amp.

My existing (commercial) tube preamp has sub-optimal earthing arrangement which is impacting it's SE outputs. This is partially mitigated by a 'ground loop breaker (diodes, R, C)' but seeking an alternative option.
  Reply With Quote
Old 18th January 2020, 03:55 AM   #112
Harryputter is offline Harryputter
diyAudio Member
 
Join Date: Feb 2019
Thanks for the fantastic DIY buffer amp. I plan to use it when making my preamp. If I want Balance and SE input and output, al least two of it would be needed?
  Reply With Quote
Old 18th January 2020, 05:47 AM   #113
acg is offline acg  Australia
diyAudio Member
 
Join Date: Oct 2013
Location: Sunshine State
Quote:
Originally Posted by Class D View Post
If you could publish all the same specs into a 600R load, it would be very useful information for many of the use cases of this board.
Yes, this. My situation is power amps with 5k input impedance. Would be interesting to see some measurements for both some gain and a tougher load than 100k.
  Reply With Quote
Old 18th January 2020, 05:53 AM   #114
Class D is offline Class D  Canada
Banned
 
Join Date: Jan 2020
Quote:
Originally Posted by acg View Post
Yes, this. My situation is power amps with 5k input impedance. Would be interesting to see some measurements for both some gain and a tougher load than 100k.
Yes the 2v output and 100K input measured results are great for getting a bunch of oooh's and ahhhh's from the numbers guys. But certainly doesn't reflect a real world application. I'd like to see 600R with 10V output.

Kinda like saying your car can do 200mph. But only when doing a burnout on an ice patch.

Last edited by Class D; 18th January 2020 at 05:57 AM.
  Reply With Quote
Old 18th January 2020, 06:28 AM   #115
Class D is offline Class D  Canada
Banned
 
Join Date: Jan 2020
10v and 600R is a pretty standard test condition. If we look at the That 1646 for example, that's what they use in the data sheet:

http://www.thatcorp.com/datashts/THA..._Datasheet.pdf
Attached Images
File Type: png Screen Shot 2020-01-17 at 10.24.46 PM.png (31.2 KB, 262 views)
  Reply With Quote
Old 18th January 2020, 07:47 PM   #116
tomchr is offline tomchr  Canada
diyAudio Member
 
tomchr's Avatar
 
Join Date: Feb 2009
Location: Calgary
Quote:
Originally Posted by Class D View Post
Yes the 2v output and 100K input measured results are great for getting a bunch of oooh's and ahhhh's from the numbers guys. But certainly doesn't reflect a real world application.
No? Common input impedances for amps tend to sit around 47-48 kΩ. As you pointed out earlier, the difference between that and 100 kΩ is largely academic.

Quote:
Originally Posted by Class D View Post
I'd like to see 600R with 10V output.
Your four posts requesting this clearly indicate your interest in this data point. Will you allow me to measure it for you or do you intend to continue to throw my product under the bus with your trolling?

Quote:
Originally Posted by Class D View Post
Kinda like saying your car can do 200mph. But only when doing a burnout on an ice patch.
What evidence do you have to suggest that's the case for the Universal Buffer?

Oh, and welcome to DIY Audio, by the way. Or should I say, "congratulations on your reincarnation on DIY Audio"? Of your 19 posts since yesterday when you signed up (again), about 75 % have been throwing products under the bus, so I must say that you're off to a running start.

Anyway. So far, I have two action items regarding the Universal Buffer:
  1. THD+N vs output level at various gains
  2. THD+N vs output level at 600 Ω load
I should be able to fit that in around the middle of next week. I need parts from Mouser to take the THD+N measurements at various gains.

Tom
__________________
Modulus-86, 186, 286, & 686: 40-240W (8Ω), <-120dB THD. HP-2 Headphone Amp: 660mW, <-130dB THD. Taming the LM3886.
Neurochrome : : Audio - www.neurochrome.com - Engineering : : Done : : Right
  Reply With Quote
Old 18th January 2020, 08:06 PM   #117
Class D is offline Class D  Canada
Banned
 
Join Date: Jan 2020
It was just a simple request to see what this board can do under industry standard test conditions. Not sure how that is "throwing it under the bus"??

Not sure why anyone would need this buffer to drive 2v into a 100k load. What source gear that can drive the 50k input impedance of this board can't do that already? I'm a bit confused.

It appears many people have plans to use this buffer in front of the Purifi amp kit. Which means it will need to drive 10v into a 2200R load. 600R is a standard input impedance test level, and likely a preset already in your analyzer. Which is why I picked it.
  Reply With Quote
Old 18th January 2020, 08:25 PM   #118
tomchr is offline tomchr  Canada
diyAudio Member
 
tomchr's Avatar
 
Join Date: Feb 2009
Location: Calgary
OK. So five requests for testing with 600 Ω load. Got it!

Please see Post #116 where I've committed to taking that measurement. I'll add 2 kΩ load as well. Do we need to argue further or will you allow me time to perform the testing?

Tom
__________________
Modulus-86, 186, 286, & 686: 40-240W (8Ω), <-120dB THD. HP-2 Headphone Amp: 660mW, <-130dB THD. Taming the LM3886.
Neurochrome : : Audio - www.neurochrome.com - Engineering : : Done : : Right
  Reply With Quote
Old 18th January 2020, 08:27 PM   #119
Class D is offline Class D  Canada
Banned
 
Join Date: Jan 2020
Quote:
Originally Posted by tomchr View Post
OK. So five requests for testing with 600 Ω load. Got it!

Please see Post #116 where I've committed to taking that measurement. I'll add 2 kΩ load as well. Do we need to argue further or will you allow me time to perform the testing?

Tom
Just inquiring on why those test conditions where chosen to showoff what this board can do. That's all.

If you could provide an example of a typical use cause where this board would be used under those conditions, and why this buffer would be beneficial in this particular application, it would clarify things a bit more for me.
  Reply With Quote
Old 18th January 2020, 08:37 PM   #120
tomchr is offline tomchr  Canada
diyAudio Member
 
tomchr's Avatar
 
Join Date: Feb 2009
Location: Calgary
Light load will always show the best performance, so I chose that operating point to start. As you can see in Post #116 and #118, I am adding other data points.

There is only one of me and only 24 hours in my day. I have other competing priorities as well. Making five requests and demanding justification for anything you happen to read between the lines will only distract me from taking the measurements. If your goal is to have those measurements provided, I hope that you are able to see that you are working against yourself here. Unless you're trolling, or have a competing product to sell. In those cases, it would obviously be in your best interest to keep me distracted.

A typical use case would be a preamp with differential output: Source -> Volume Pot -> Universal Buffer. In that case, the Buffer is likely to see a 48 kΩ differential load.

Tom
__________________
Modulus-86, 186, 286, & 686: 40-240W (8Ω), <-120dB THD. HP-2 Headphone Amp: 660mW, <-130dB THD. Taming the LM3886.
Neurochrome : : Audio - www.neurochrome.com - Engineering : : Done : : Right
  Reply With Quote

Reply


Universal Buffer achieving -140 dBc (0.00001 %) THDHide 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
Introducing Mercury - Achieving escape velocity. Russ White Twisted Pear 206 11th February 2020 12:38 AM
Universal buffer/headamp based on OPA1622 OlegSh Headphone Systems 337 8th December 2019 05:20 PM
Universal Buffer/HP Amplifer Bonsai Headphone Systems 20 30th August 2014 07:06 PM
Universal FET buffer / preamplifier veteran Analog Line Level 31 21st May 2013 10:42 PM
Universal Class A line Level Buffer Bonsai Solid State 2 22nd February 2011 06:09 AM


New To Site? Need Help?

All times are GMT. The time now is 02:13 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
Copyright ©1999-2020 diyAudio
Wiki