Author Topic: Connecting a laptop directly to a power amplifier?!  (Read 319 times)

Offline Zilch510

Connecting a laptop directly to a power amplifier?!
« on: May 23, 2020, 04:15:00 PM »
Okay, so as some of ye may know, I have an Adcom GFA-1 that I use for playing music on a daily basis.

Because I traded some stuff (and a bit of money) for the amp, I decided to be my regular cheap-ass self and not get a preamp.

Instead what I do is connect a really cheap (R300?) Bluetooth thingy directly to my amp. On occasion I'll use my dads laptop with an equalizer (EqualizerApo).

Is it fine? Is it safe? I need answers!

Thanks in advance ;)
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Offline Hi-Phibian

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Re: Connecting a laptop directly to a power amplifier?!
« Reply #1 on: May 23, 2020, 04:40:03 PM »
Fairly safe.  Imo the risk is accidentally having the volume at max and playing something that could damage the speakers. 

I would put a potentiometer(“passive pre amp/volume control”)  in between.  The knob is a better visual indicator and takes less time to turn down.   


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Offline d0dja

Re: Connecting a laptop directly to a power amplifier?!
« Reply #2 on: May 23, 2020, 04:59:38 PM »
What croak said. Also if you have little plastic thingies hooked up by minijack cables you have a big risk of a connection crackle at 0dB.
If you don't turn your laptop more than (say) half, make a little voltage divider on your rca plugs in the cable you going to make up. If you just gotto guess make it for a 60k ohm lpad. The terms used all easily googlable.

This would work ... a little valve buffer. FX-Audio Tube-01. I got one to get rid of.


Offline Zilch510

Re: Connecting a laptop directly to a power amplifier?!
« Reply #3 on: May 23, 2020, 05:16:46 PM »
This would work ... a little valve buffer. FX-Audio Tube-01. I got one to get rid of.

If it's free, it's for me😜
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Offline bbe22

Re: Connecting a laptop directly to a power amplifier?!
« Reply #4 on: May 23, 2020, 08:00:36 PM »
 potentiometer(“passive pre amp/volume control”


eg

 https://www.mantech.co.za/ProductInfo.aspx?Item=65M0415-H     and 4 female rca  2 in   2 out   , some wire in a small box , and your are safe,  and done :)

Offline Hi-Phibian

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Re: Connecting a laptop directly to a power amplifier?!
« Reply #5 on: May 23, 2020, 08:23:06 PM »
potentiometer(“passive pre amp/volume control”


eg

 https://www.mantech.co.za/ProductInfo.aspx?Item=65M0415-H     and 4 female rca  2 in   2 out   , some wire in a small box , and your are safe,  and done :)


Or on the real cheap cut a Chinese cheap lead in half and solder the open ends on the pot.   Tape or heatshrink it or mount in some disposable Tupperware. 


.
Croak Audio
Analogue by birth, digital by design. Mostly a StereoType though known to enjoy some Mono too https://wa.me/27835651236?text=AVF%20 http://www.croak.co.za

Offline Zilch510

Re: Connecting a laptop directly to a power amplifier?!
« Reply #6 on: May 23, 2020, 09:59:47 PM »
Ohhh, I like the Tupperware idea😏

I might even put some weights in it🤷‍♂️
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Offline Adagio

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Re: Connecting a laptop directly to a power amplifier?!
« Reply #7 on: May 24, 2020, 05:01:55 AM »
:facepalm:

Offline GoodEnoughGear

Re: Connecting a laptop directly to a power amplifier?!
« Reply #8 on: May 24, 2020, 07:14:44 AM »
JRiver has a safety feature for digital volume control that is pretty cool:

https://wiki.jriver.com/index.php/Volume#Volume_Protection

"Volume Protection is a feature to prevent unexpectedly loud output. It is useful in cases where you connect Media Center to a high-gain amplifier where unexpected output at full volume could damage equipment or your ears.

Volume protection does the following:

Makes it so that it isn't possible to increase the volume by more than 5% at a time (so accidentally clicking 100% on the slider will not go to 100%)
Makes it so that the volume can not be increased by more than 20% a second
Makes it so that starting playback if nothing has played for 30 minutes sets the volume to 20% (unless the volume is already lower)"
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Offline adie

Re: Connecting a laptop directly to a power amplifier?!
« Reply #9 on: May 24, 2020, 09:50:48 AM »
JRiver has a safety feature for digital volume control that is pretty cool:

https://wiki.jriver.com/index.php/Volume#Volume_Protection

"Volume Protection is a feature to prevent unexpectedly loud output. It is useful in cases where you connect Media Center to a high-gain amplifier where unexpected output at full volume could damage equipment or your ears.

Volume protection does the following:

Makes it so that it isn't possible to increase the volume by more than 5% at a time (so accidentally clicking 100% on the slider will not go to 100%)
Makes it so that the volume can not be increased by more than 20% a second
Makes it so that starting playback if nothing has played for 30 minutes sets the volume to 20% (unless the volume is already lower)"

Plus you can set a maximum volume anywhere below 100%.
Of course JRiver costs a few hundred rands.

Offline sajunky

Re: Connecting a laptop directly to a power amplifier?!
« Reply #10 on: May 24, 2020, 09:35:19 PM »
Foobar 2000 is free. Just set it up in bit-perfect mode for the best SQ.
If it measures good and sounds bad—it's bad. If it measures bad and sounds good, you've measured the wrong thing.
/ Daniel R. von Recklinghausen, Chief Engineer, H.H. Scott/