Commercial Gainclone kit- building instructions - Page 171 - diyAudio
Go Back   Home > Forums > Commercial Sector > Vendor Forums > Audio Sector

Audio Sector Kits & PC boards from AudioSector

Reply
 
Thread Tools Search this Thread
Old 15th November 2013, 09:48 PM   #1701
diyAudio Member
 
Join Date: Jun 2013
Quote:
Originally Posted by stijn001 View Post
Thanks udaily, if you are so in the know, you could have just answered my question. But instead you chose to try and patronize me. That gives me the impression you are not a very pleasant person, prove me wrong. Please be assured that, I did "read" his comment very well, I Googled "rf filter calculator" and several other combinations and did not find what I was looking for, hence I asked the question. Don't believe me if that's your disposition, but donít blame me for it.
Guitar Pedals: R-C Filter Calculator

rc_simple_filter [Electron Coaxing Techniques & Notes]

First two on google with search term 'input roll off calculator' - you tried once and gave up?

udaily was not being condescending at all, that is not his way. He gave you the info you needed to help yourself. It's a better method of learning and teaching.
  Reply With Quote
Old 15th November 2013, 11:01 PM   #1702
diyAudio Member
 
Join Date: Dec 2011
Nop, you are both wrong, I did try and look for an answer for about 20min, read a few pages and a wiki, found a couple of formula’s that I couldn't figure out the variables for etc.., but no calculator template.

I still don't see how I could have deducted from Andrew reply that 'input roll off calculator' was the search term to use. But hey I only have an MSc degree with honors from UCL & worked in ICT and telecommunication for 20 odd years, what would I know about finding information online.

Thanks anyway for answering my question. I hope I can return the favour sometime soon. It's easy when you know what to look for, isn't it? ;-)

On what ground did you assume I didn’t make any effort in the first place, to find an answer? And yes, since the answer to that question is “none” (ie you had no ground), imo you are both pretty condescending in your replies. If not, what would you consider “condescending” to mean? You have no idea whom you are addressing, right? Think about it.

Last edited by stijn001; 15th November 2013 at 11:11 PM.
  Reply With Quote
Old 15th November 2013, 11:11 PM   #1703
diyAudio Member
 
Join Date: Jan 2013
Isn't it funny how people who use the arguement
"I've done [insert job title] for [xxx number] of years"
Seem to be the most objectionable?
- stijn, that's my nice way of saying bite your tongue, the only one looking a fool is you.
  Reply With Quote
Old 16th November 2013, 08:06 AM   #1704
AndrewT is offline AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
Quote:
Originally Posted by AndrewT View Post
................The F-3dB (= 1 / 2 Pi R C) is usually set..................

RF filtering.
The series resistor and the following shunting resistor to Signal Ground form a low pass filter that attenuates the high frequencies............Listen and decide what suits you.
Start with F-3dB @~50kHz and see if that is audible. You may have to go as high as 300kHz to make this RF filter inaudible for you and your system.
Note there is a typing error: It should say "The series resistor and the following shunting capacitor to Signal Ground form a low pass filter.

Quote:
Originally Posted by stijn001 View Post
.............Is there an online calculator or formula in which I can plug in the two resistor values to determen the RF cut-off frequency?
Quote:
Originally Posted by stijn001 View Post
............ you could have just answered my question. ..............
Quote:
Originally Posted by stijn001 View Post
Nop, you are both wrong, I did try and look for an answer..........................On what ground did you assume I didn’t make any effort in the first place, to find an answer?..............
Just read my reply.
I gave the standard "online calculator" for a single pole filter.
I gave you a start and end value for the filter F-3dB frequency.
I gave the the physical layout of the TWO components required to create that RF attenuating filter.
Just read the reply, instead of complaining.
__________________
regards Andrew T.

Last edited by AndrewT; 16th November 2013 at 08:10 AM.
  Reply With Quote
Old 16th November 2013, 01:02 PM   #1705
diyAudio Member
 
Join Date: Dec 2011
Andrew, Sorry if it appeared to you as if I was complaining about your post, that was never my intention and I’m very appreciative of you input and that of others in order to be able to build my first GC.

I merely responded to Udaily’s reply suggesting I hadn’t read your post and then responded to Passive420 for suggesting “I gave up”. Neither of which was the case.

I’m very surprised to be receive all these accusations in this thread, by merely posting a question, bizarre..
  Reply With Quote
Old 26th November 2013, 03:29 PM   #1706
Just DIY!
diyAudio Member
 
pinnocchio's Avatar
 
Join Date: Sep 2010
Location: Montreal
Quote:
Originally Posted by phil g View Post
This my first post so please forgive me if this is wrong place to ask this question.
I recently put together one of the LM4780 boards from Audiosector (to use in stereo for testing before finishing the whole kit).
I have tried three different potentiometers but there seems to be very little attenuation and certainly not all the way down to cut off.
The first two, a 10k and 20k (with a "B" designation I assume for "Linear") the attenuation is faint at best and not down to silence.
The third pot, is one retrieved from my old Technics amp with the makings of 100k Ohm B. This one does noticeably attenuate but not to cut off. To help make it clear what I am saying, the volume goes from loud to less loud.
Power is from 18v +- rails and rectifiers to 26.5v and 25v.
Thank you for any assistance on this question.
Phil
Hi Phil,

Pin 1 should go to signal ground on PCB and RCA jacks then pin 2 (wiper) to amplifier and pin 3 to preamp output.

See image below under volume control

Click the image to open in full size.

Ciao!
Do
__________________
PREAMPs : AMB α10 + JC-80 clone | Balanced DCB1 | LDR3x | AMPs: AMB β24 | Aleph 5 | VSSA | ML-2 | Fetzilla | Telos 390 Clone | My_Ref FE
DACs : TPA Buffalo II + OPC's NTD1 I/V | TPA OPUS + IVY III Speakers : Jim Holtz Statements | Astasia SD | Tubasson Mark 2
  Reply With Quote
Old 1st December 2013, 11:52 PM   #1707
bobfig is offline bobfig  United States
diyAudio Member
 
Join Date: Aug 2009
Location: H-Town
Send a message via Yahoo to bobfig
hi guys haven't been on in a while but i have a question that i need help me with.

i would like to add a auto on/off circuit to the amp and need some way of implementing it.

i plan on using the amp for tv sound and would like to have it turn on and off with the tv. it will be using rca inputs.
  Reply With Quote
Old 2nd December 2013, 08:43 AM   #1708
AndrewT is offline AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
ESP has an auto turn ON/OFF circuit.
__________________
regards Andrew T.
  Reply With Quote
Old 12th January 2014, 08:17 PM   #1709
diyAudio Member
 
Join Date: Dec 2013
Dear Peter D.,

I have received your LM4780 kit, it looks great.

In the first place I planned to build the kit in parallel configuration but because I have speakers that can be bi-amped (Mission M52) I'm considering to build the kit 2 x stereo.

My question is what you think will sound better.

I guess that in parallel mode the overall power output will be higher but if the sound quality in double stereo mode will be much better its something I can live with.

Also I probably can use a smaller toroid for powering the tweeters I guess.

Any info would be very welcome.

Greetz,

Joery
  Reply With Quote
Old 13th January 2014, 04:37 PM   #1710
diyAudio Member
 
Join Date: Dec 2013
Because I want to continue I have ordered a 500VA 2x25V toroid transformer, I hope I can still use this one to power the 2 different configurations.
  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
Commercial complete Gainclone kit for a beginner? gychang Chip Amps 365 4th October 2011 08:19 AM


New To Site? Need Help?

All times are GMT. The time now is 12:41 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