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

Analog Line Level Preamplifiers , Passive Pre-amps, Crossovers, etc.

Attenuation
Attenuation
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 22nd August 2005, 07:35 PM   #1
argonrepublic is offline argonrepublic  Canada
diyAudio Member
 
Join Date: Apr 2005
Location: Simcoe Ont
Default Attenuation

Presently I am running my amp around .775VRMS the amp is rated 1.4VRMS in = 100WRMS out.
It is possibly a little underdriven but it sounds pretty good (better than any active studio monitors I've tried). Any more input voltage and It would be uncomfortably loud in nearfield position.
I am considering an ART DIO in place of Delta1010 D/A possibly get a bit more detail and free up a stereo bus.
The DIO has an output of about 6Volts. The ART tech says that I can use resistors in series. It is my understanding that resistors cause compression thus reducing dynamics. I need to drop from 6V to around 1V.
Any suggestions?
  Reply With Quote
Old 22nd August 2005, 07:51 PM   #2
AndrewT is offline AndrewT  Scotland
R.I.P.
 
Join Date: Jul 2004
Location: Scottish Borders
Hi,
are you using analogue volume control or digital volume control?
I don't know your equipment.
__________________
regards Andrew T.
  Reply With Quote
Old 22nd August 2005, 08:32 PM   #3
jan.didden is offline jan.didden  Europe
diyAudio Member
 
jan.didden's Avatar
 
Join Date: May 2002
Location: The great city of Turnhout, BE
Default Re: Attenuation

Quote:
Originally posted by argonrepublic
Presently I am running my amp around .775VRMS the amp is rated 1.4VRMS in = 100WRMS out.
It is possibly a little underdriven but it sounds pretty good (better than any active studio monitors I've tried). Any more input voltage and It would be uncomfortably loud in nearfield position.
I am considering an ART DIO in place of Delta1010 D/A possibly get a bit more detail and free up a stereo bus.
The DIO has an output of about 6Volts. The ART tech says that I can use resistors in series. It is my understanding that resistors cause compression thus reducing dynamics. I need to drop from 6V to around 1V.
Any suggestions?
Don't worry, resistors do not cause any compression (unless you try to force a kW through a 1/4 w resistor ).

Possibly the only thing you need to do is to turn down your volume control, but that depends a bit on your configuration. If you have a gain or buffer stage ahead of the vol control, that stage *could* be overdriven. If you go directly in on the vol control, that will not be a problem.

Anyway, you can always use a resistive divider 6:1 or something (the exact ratio is very uncritical). Like a resistor of 10k in series with the DAC output into your equipment, and a resistor of 1.5k from the equipment input to ground.

Jan Didden
__________________
Cable: a potential source of trouble interconnecting two other potential sources of trouble - Erik Margan
Linear Audio pubs and articles . The SilentSwitcher now at diyaudio store SilentSwitcher. Keeping in touch with SY.
  Reply With Quote
Old 23rd August 2005, 12:21 AM   #4
argonrepublic is offline argonrepublic  Canada
diyAudio Member
 
Join Date: Apr 2005
Location: Simcoe Ont
Default attenuation

I have no volume control except in software which I seldom use. I may look into a vishay dale attenuator but for now it works great. If it seems too loud it's because of a problem in the mix or I am tired (time to shutdown). It has been a long journey getting the champagne sound on a ginger ale budget and the idea of using an attenuater makes me nervous. My room, amp, speakers and sub are almost perfectly linear in my chair at 85dB
  Reply With Quote
Old 23rd August 2005, 12:24 AM   #5
argonrepublic is offline argonrepublic  Canada
diyAudio Member
 
Join Date: Apr 2005
Location: Simcoe Ont
Default attenuation

By digital volume control, do you mean something that will attenuate spdif digital stream?
That sounds like a great concept.
I would like that option but it is unfamilliar to me
Thanks
  Reply With Quote
Old 23rd August 2005, 07:22 AM   #6
AndrewT is offline AndrewT  Scotland
R.I.P.
 
Join Date: Jul 2004
Location: Scottish Borders
Hi,
it sounds like you already have a digital volume control. But it is defaulting to an acceptable volume. Check that it never overloads the digital stages and run it as high as you can without overloading
Q. other than listening for distortion, is there any way to check that digital overload is not happening?
Now add an attenuator to the output of your source but at the end of the cable next to the amps. This keeps the cables into the amp short to preserve the treble.
As Janneman said you need a line resistor AND a resistor to ground.
10k for line is OK, a selection for ground connection or a 2k0 pot to give variable attenuation. Repeat this for each channel.
__________________
regards Andrew T.
  Reply With Quote

Reply


AttenuationHide 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
attenuation using I/V ailouros6 Digital Source 14 15th October 2008 06:20 PM
XLR to RCA with attenuation pad. KOL69 Everything Else 1 24th April 2008 11:10 PM
hum attenuation AndrewT Power Supplies 3 2nd July 2006 09:12 PM
10 dB attenuation box june Parts 2 20th July 2004 04:07 AM
Attenuation Nappylady Multi-Way 3 18th February 2003 12:07 PM


New To Site? Need Help?

All times are GMT. The time now is 06:33 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 16.67%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki