DIY Audio Projects Forum
 NEW  Matt presents bias and operation data for the 6V6 tube in SE operation - 6V6 Single-Ended (SE) Ultra Linear (UL) Bias Optimization.

DIY Audio Projects Forum

Welcome to the DIY Audio Projects Message Forum. Use these forums to discuss Hi-Fi audio and to share your DIY Audio Projects. Registration is free and required to post messages and view the file attachments. Registration will only take a minute and registered users do not see any advertisements. After you have completed the online registration process, check your email (including spam/junk folder) for the verification email to activate your account. New members are under moderation - so your posts will not be visible until approved by a moderator. See the Read Me 1st, Forum RULES and Forum FAQ to get started on the forum.

It is currently 05 Apr 2020, 19:24

All times are UTC - 6 hours [ DST ]




Post new topic Reply to topic  [ 2 posts ] 
Author Message
PostPosted: 03 Nov 2015, 08:37 
Offline

Joined: 03 Oct 2012, 12:34
Posts: 5
Location: padova, Italy
Hi everybody,
I'm quite new to the world of electronics and I'd like to build a simple audio circuit which would also suit my needs in live applications, especially when input channels on mixers are limited.
What I want to do is a balanced XLR stereo to mono summing box, which I can use, for example, for keyboards.
In addition, I'd like to add a phase switch on one of the two inputs (DPDT switch?) and a PAD on just one input aswell.
This way I could use it as a snare top/bottom combiner (using two mics), with the pad used to tame the bottom snare.
I'll start off saying I have quite few understandings of the huge world of electronics, after searching the web I have a rough idea of how to start but i still have some doubts.
I think it would be good to start with this circuit http://www.rane.com/n109fig3.gif
placing the phase switch just before the points where the two sources join.
Regarding the pad switch, should I integrate a H PAD?
I found a calculator http://www.nu9n.com/tpad-calculator.html
from my poor understanding, I suppose that the summed input and output resistors on the PAD channel should match the values of the ones on the unaffected channel (correct me if I'm wrong) .
But what about the behaviour of that bridge power load resistance once the Pad kicks in? Will it affect the channel input impedance, hence the two inputs have now different impedances? Or is that negligible?
Will keeping its value as low as possible minimize its effect (again, if this is really something undesirable)?

Sorry for asking a lot of questions, but as I said I'm quite new and inexpert and I don't know directly any electronics expert :)
Thanks a lot to anyone who will respond and will give me an help about this.


Top
 Profile  
 
PostPosted: 04 Nov 2015, 11:04 
Offline
Project Author
User avatar

Joined: 04 Jun 2008, 20:59
Posts: 4100
Location: Arizona, USA
Hi, A tad bit out of my usual areas..but I would consider either an assembled matcher or getting the matcher transformers from EDCOR to do this diy. My sense is that using transformers will do a few things that the resistive one can not. First you can arrange it for electrical isolation of the two inputs as well as the output. It would be able to ground lift each from each other. Second you can flip the phase of either input or even the output if desired. Third it would have lower signal loss. Just some thoughts.

Good listening
Bruce

_________________
Some of my DIY Tube Amplifier Projects:


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 2 posts ] 

All times are UTC - 6 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 3 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
DIY Tube Projects :: DIY Tube Amp Kits :: DIY Speaker Projects :: DIY Solid State Projects :: DIY IC / Op-amp Projects :: DIY Phono Projects :: DIY Cable Projects :: Hi-Fi Audio Schematics
© diyAudioProjects.com - Terms of Service - Privacy Policy