Marbles:
Do you think the gains are turned up too high? What would you suggest using to set gains? I don't have any testing equipment except for a multitester.
Do you think the gains are turned up too high?
What would you suggest using to set gains?
There are two solid ways to set the gain controls on amplifiers.
1) the more proper way, though most people don't have the equipment is to set a signal generator up on the input of the amp. Use a typical sine wave at a frequency of 1kHz. Hook an oscilloscope up on the amps output so you can measure the 1kHz signal. Then turn the gain up until what was once a nice sine wave on the scope starts to turn into a square wave. That indicates that the amp is clipping. So turn back the gain so you see that nice sine wave again. Finally sweep the generator from 10Hz to 20kHz and verify that the signal looks fine through that range on the scope.
2) the every-day Joe way. Turn your source to 3/4 volume (in this case Winamp). Turn the gain pot up on the amp until the music sounds like crap (amp clipping). Turn back until music is loud, but still sounds all together. You'll know what I mean if you experience it. That's all folks.
Marbles_00 wrote:All I know is that from now on, I'm going to make sure that I listen to some "normal" music after my kid's listen to theirs. My Nowplaying image makes me look like a FREAK
ya, i totally missed the first link!Marbles_00 wrote:I think you missed the signal detection circuit (first one listed). It detects audio signals and if the signals exceed a pre-determined level, a relay closes...powering the amps. It is the sort of circuit used in a power subwoofer.
i see that the left and right signals tie together, but they both have a 10k resistor in front of them. do you think that this is enough impedence to make the signal effects negligable, or do you think that i need some sort of isolation.Marbles_00 wrote:Since looking over the circuit more, I'm not too sure if it is designed for stereo use as both left and right channels goto the same point. In my eyes that would allow the left channel to drift to the right and vise versa. Though for a powered amp, who cares, but for something like how you'd want to use it, then you would only want to hook up one channel...still requiring three seperate first stages.
A signal feed is taken from both Left and Right channels via R1 and R2 (leave out one input resistor for a mono source such as a sub-woofer).
The 10k input resistors may introduce some crosstalk if the drive amp has high output impedance, but this is unlikely to cause a problem with the majority of preamps.
i would go to a pawn shop
i wouldnt recomend a 6chanell amp unless you have cheap speakers, because an amp with that many channels has too little power per chanel to power quality speakers properly
you cant find good quality amps anymore because everyone just wants 7.1 surround sound, and the sacrifice for quantity is always in quality.
I am trying to figure out exactly how all this works