Tube-I-zator Professional PCB - Page 80 - diyAudio
Go Back   Home > Forums > Commercial Sector > Group Buys

Group Buys Members group buys

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 9th April 2013, 07:21 PM   #791
diyAudio Member
 
Join Date: Oct 2010
Location: Slovakia
Hi dvb-projekt

DDAC PCM1794A NOS Doede use this I/V resistor:
Attached Images
File Type: jpg R_IV.JPG (45.9 KB, 250 views)
  Reply With Quote
Old 9th April 2013, 08:59 PM   #792
diyAudio Member
 
dvb projekt's Avatar
 
Join Date: Feb 2009
Location: Willich, Germany
Blog Entries: 37
Send a message via Skype™ to dvb projekt
Quote:
Originally Posted by dvb-projekt View Post
Thanks



Sure. Please ask Doede witch I/V resistor value , Tubes and Rk value he recommend.

Quote:
Originally Posted by jeremysk View Post
Hi dvb-projekt

DDAC PCM1794A NOS Doede use this I/V resistor:
You should ask Doede about the I/V and Rk resistor value for a SRPP stage like the Tube-I-zator, witch is different from his standard design value

__________________
Reference TDA1541A DAC project PCBs / Tube-I-zator PCB / SSHV-Shunt PCB
Stock status in my Blog
  Reply With Quote
Old 10th April 2013, 02:34 PM   #793
Crom is offline Crom  United Kingdom
diyAudio Member
 
Join Date: Oct 2012
Hi Oliver,

Is is OK to add R26-R31 from your V3 schematic to my V2 boards?

I am running 2 x tube-i-zators v2 in a balanced, dual mono format with 2 x Bullalo IIISEs. I am currently using 20R I/V resistors but have ordered 4 x 30R Rhopoint's to try out.

I obviously don't need the 1541-specific mods but what will the difference be having made the mods?

Any difference in values for balanced/dual mono build?

Cheers,
Crom
  Reply With Quote
Old 10th April 2013, 03:46 PM   #794
tmas is offline tmas  United States
diyAudio Member
 
Join Date: Nov 2008
Hi Crom,

Just wondering why you are going from 20R to 30R for you I/V resistors?
  Reply With Quote
Old 10th April 2013, 05:51 PM   #795
Crom is offline Crom  United Kingdom
diyAudio Member
 
Join Date: Oct 2012
Quote:
Originally Posted by tmas View Post
Just wondering why you are going from 20R to 30R for you I/V resistors?
Good question tmas ;-)

The simple answer is that Rhopoint doesn't have 20R in stock.

The longer answer is that I've been playing with various values of resistor and decided that I am unable to tell any difference. noizas kindly gave me some theory behind the value choice so that I can try the measured approach. I've found that the Sabre produces 3.903mA p-p per channel but still working on finding the output voltage so that I can try out noizas' equations. I've tried posting on twisted pear forum but Russ/Bryan don't seem to want to help. In the meantime, I got impatient ;-)


Cheers,
Crom
  Reply With Quote
Old 11th April 2013, 05:09 AM   #796
diyAudio Member
 
dvb projekt's Avatar
 
Join Date: Feb 2009
Location: Willich, Germany
Blog Entries: 37
Send a message via Skype™ to dvb projekt
Quote:
Originally Posted by Crom View Post
Hi Oliver,

Is is OK to add R26-R31 from your V3 schematic to my V2 boards?

I am running 2 x tube-i-zators v2 in a balanced, dual mono format with 2 x Bullalo IIISEs. I am currently using 20R I/V resistors but have ordered 4 x 30R Rhopoint's to try out.

I obviously don't need the 1541-specific mods but what will the difference be having made the mods?

Any difference in values for balanced/dual mono build?

Cheers,
Crom
Hi Crom,

you could add easily the two 1M0 pull down resistors (R30 & R31) to keep the output of the coupling cap at GND potential. Otherwise equipment could be damaged when connected (high voltage on the output when the coupling cap is discharged).

If you havent problems with oscillations, you could omit the 1K5 grid stoppers (R26-R29). Because of the new layout for the V3, John recommended to add these resistors.

The values stays also for balanced/dual mono builds.

Best regards,
Oliver

__________________
Reference TDA1541A DAC project PCBs / Tube-I-zator PCB / SSHV-Shunt PCB
Stock status in my Blog
  Reply With Quote
Old 11th April 2013, 10:33 PM   #797
tmas is offline tmas  United States
diyAudio Member
 
Join Date: Nov 2008
Quote:
Originally Posted by Crom View Post


Good question tmas ;-)

The simple answer is that Rhopoint doesn't have 20R in stock.

The longer answer is that I've been playing with various values of resistor and decided that I am unable to tell any difference. noizas kindly gave me some theory behind the value choice so that I can try the measured approach. I've found that the Sabre produces 3.903mA p-p per channel but still working on finding the output voltage so that I can try out noizas' equations. I've tried posting on twisted pear forum but Russ/Bryan don't seem to want to help. In the meantime, I got impatient ;-)


Cheers,
Crom
Hi Crom,

Please keep us posted on your findings. I will be building my dual mono Buffalo 3 with Tube-I-Zator soon.
  Reply With Quote
Old 12th April 2013, 10:12 AM   #798
Crom is offline Crom  United Kingdom
diyAudio Member
 
Join Date: Oct 2012
Quote:
Originally Posted by tmas View Post
Please keep us posted on your findings.
No problem, I received the 30R Rhopoints yesterday and fitted them last night. Sounded pretty good immediately but after a couple of hours I completely concur with what Oliver has said. Revelatory !!!! I needed to buy 4, so that's about 60 GBP - no mean sum - but well worth it in my opinion. All the instruments take on a little more of a holographic presentation ... like they have more depth, texture and sort of 3d quality to them...sounds mental, but true. I tried it again this morning and there's even a little less harshness in vocals and perceptively more detail. Perhaps the more detail is because there's less harshness. One thing I probably should do is go back to 30R PRPs to remove the increased resistance from the equation but I'm not sure I can be bothered at the moment - it just sounds stunning.

NB - in my build I've already replaced the 200R Rk with Texas Components but the R I/Vs I was using were the standard BOM PRP9372 (ie I hadn't upgraded the R iv to the texas components)...maybe that's why it was such a big leap for me because I know Oliver has said that the TCC metal films are excellent as Ri/v.

I'm using them with my current fave tube, the full music. I've also got some NOS Mullards which sound great but I love the detail of the FMs.

I should get v2-v3 extra resistors today/tomorrow.

@Oliver - how can I know/measure if I'm getting oscillations?

Cheers,
Crom
  Reply With Quote
Old 12th April 2013, 02:24 PM   #799
tmas is offline tmas  United States
diyAudio Member
 
Join Date: Nov 2008
Oliver has said that the TCC metal films are excellent as Ri/v.


Crom,
I am not familiar with the TCC metal films?
  Reply With Quote
Old 24th April 2013, 07:12 AM   #800
Crom is offline Crom  United Kingdom
diyAudio Member
 
Join Date: Oct 2012
Quote:
Originally Posted by tmas View Post
Crom,
I am not familiar with the TCC metal films?
Sorry tmas, I was over-shortening...look here:

http://www.diyaudio.com/forums/blogs...-resistor.html

I was referring to the Texas components corporation resistors that Oliver had recommended in the past.
  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
STK Professional V-6 Amp--need schematics wcarthur Instruments and Amps 0 21st April 2009 01:59 PM
I need a professional opinion... sparky3489 Car Audio 0 25th June 2006 03:31 AM
professional opinion rv1890 Multi-Way 2 12th January 2005 04:22 PM
Professional Anodizing - How to? tiroth Everything Else 20 30th January 2004 08:15 PM
Anyone tried Professional DIY PHILIPS CD kit ??? till Digital Source 6 4th June 2002 10:06 AM


New To Site? Need Help?

All times are GMT. The time now is 06:22 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