Preamps and line level...

Fedess · 4th August 2011, 12:19 AM

Hi,

I'm just interested in hearing yours opinion about this preamp I want to build for my amp:

Hi-Fi Preamplifier

The OpAmps I will be using are TL072, because I can't get better ones in my country.

My amp is connected to:
-PC Soundcard
-Turntable + phono preamp
-And I have few unused inputs (for ipods, etc... just in case)

The line level of the PC soundcard is ok, and the RIAA preamp gives a loud sound volume (very similar to the PC line level). The general volume I can control with a 100k pot at the amp input.

I like the bass and treble controls of this preamp.

Do you think that the amp's input will be too high? (I can get the amp clipping when it's connected directly to PC soundcard)

Any other consideration before DIYing it? (a better or alternative circuit?) or should I just go for it?

thx!
Fedess

nigelwright7557 · 4th August 2011, 01:26 AM

You will need input coupling capacitors.
I would put 100R in series with output to output coupling capacitors.
Use plenty of decoupling, I have seen these types of tone controls oscillate at the extremes of pot travel.

Fedess · 4th August 2011, 01:32 AM

I think they already are there... take a look at "Figure 4 - Balance, Volume and Output Stage"...

Is that what you mean?

4th August 2011, 12:19 AM	#1
Fedess diyAudio Member Join Date: Jul 2010 Location: Buenos Aires	Preamps and line level... Hi, I'm just interested in hearing yours opinion about this preamp I want to build for my amp: Hi-Fi Preamplifier The OpAmps I will be using are TL072, because I can't get better ones in my country. My amp is connected to: -PC Soundcard -Turntable + phono preamp -And I have few unused inputs (for ipods, etc... just in case) The line level of the PC soundcard is ok, and the RIAA preamp gives a loud sound volume (very similar to the PC line level). The general volume I can control with a 100k pot at the amp input. I like the bass and treble controls of this preamp. Do you think that the amp's input will be too high? (I can get the amp clipping when it's connected directly to PC soundcard) Any other consideration before DIYing it? (a better or alternative circuit?) or should I just go for it? thx! Fedess

4th August 2011, 01:26 AM	#2
nigelwright7557 diyAudio Member Join Date: Apr 2008 Location: Carlisle, England	You will need input coupling capacitors. I would put 100R in series with output to output coupling capacitors. Use plenty of decoupling, I have seen these types of tone controls oscillate at the extremes of pot travel. __________________ http://www.murtonpikesystems.co.uk PCBCAD40 pcb design software.

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Convert Line Level to Electric Guitar Level	miallen	Solid State	4	16th May 2010 01:22 PM
trouble matching line level to guitar amp input level...any help?	mondogenerator	Tubes / Valves	5	19th December 2009 10:00 AM
speaker level input vs line level question	crippledchicken	Subwoofers	4	17th July 2007 03:36 AM
lesser of two evils, high level -> line level, digital volume control	mazurek	Solid State	3	19th November 2006 12:25 AM
how to bring down line level signal to preamplifier level	deji	Solid State	15	15th April 2004 04:13 PM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read


	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

4th August 2011, 01:32 AM	#3
Fedess diyAudio Member Join Date: Jul 2010 Location: Buenos Aires	I think they already are there... take a look at "Figure 4 - Balance, Volume and Output Stage"... Is that what you mean?

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)