Home » Audio » Silicon Valley » Thump on turn-on/shut-off
Thump on turn-on/shut-off [message #7792] Sun, 03 April 2005 20:40 Go to next message
hurdy_gurdyman is currently offline  hurdy_gurdyman
Messages: 416
Registered: May 2009
Illuminati (1st Degree)
I have a Marantz SR-5100 receiver with a fried power amp section. I wired up the preamp to a pair of RCA jacks and am using it just a a tuner/preamp. When turning on the receiver and power amp on or off at the same time using a power strip switch I get a loud thump/pop. I recall something about using a small cap on the preamps output to help absorb this. Anyone know how to do this, or any other cure?

Dave

Re: Thump on turn-on/shut-off [message #7793 is a reply to message #7792] Mon, 04 April 2005 01:23 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18676
Registered: January 2001
Illuminati (33rd Degree)

You might consider a delayed relay. Use a DPST relay and a 555 timer and transistor to drive it. It's a simple solution. Not as simple as a single cap or something like that, but it really isn't much effort. You can easily put it on a small perfboard and get power from the amp's internal power supply. If need be, add a 7812 regulator to bring the supply voltage down for your timer circuit.


Re: Thump on turn-on/shut-off [message #7848 is a reply to message #7792] Wed, 17 August 2005 21:01 Go to previous message
Steve is currently offline  Steve
Messages: 83
Registered: May 2009
Viscount
Hi Hurdy,

Using a small cap will lower the amplitude, but the bass response will also suffer. Wayne has a nice idea but if the circuit is too complex or no tools, one could use a more time consuming method of turn on the preamp first, then after some period of time, turn on the amp. When turning off, reverse this order.

Take care Hurdy and hope this helps.
Steve

Previous Topic: bass/guitar
Next Topic: 4-transistor linestage
Goto Forum:
  


Current Time: Fri Apr 19 15:31:19 CDT 2024

Sponsoring Organizations

DIY Audio Projects
DIY Audio Projects
OddWatt Audio
OddWatt Audio
Pi Speakers
Pi Speakers
Prosound Shootout
Prosound Shootout
Smith & Larson Audio
Smith & Larson Audio
Tubes For Amps
TubesForAmps.com

Lone Star Audiofest