I have a Class D /( possible Tripath but uncertain at the moment ) amp and the input is rated @ > 4 K ohm.
Input sensitivity @ 1 .0 V and output 4 ohm .
I understand speaker impedance loads etc but can someone explain as simply as possible how the input impedance effects things . nb i use a cd player with 2 mV output and 8ohm 86 db speakers and the amps rated @ 22 watt per channel @ 10% distortion into 4 ohm. Sorry if this is a dumb question but it's just something i don't understand in terms of performance .
Input sensitivity @ 1 .0 V and output 4 ohm .
I understand speaker impedance loads etc but can someone explain as simply as possible how the input impedance effects things . nb i use a cd player with 2 mV output and 8ohm 86 db speakers and the amps rated @ 22 watt per channel @ 10% distortion into 4 ohm. Sorry if this is a dumb question but it's just something i don't understand in terms of performance .
What do you mean by the input impedance is greater than 4k?CD players produce an average of 2 - 3 volts signal.
Please check your figures.
If the output of the source has an impedance of 10k then it will run into an input load of 10k or greater.
Most amplifiers are set at 18k or higher.
Please check your figures.
If the output of the source has an impedance of 10k then it will run into an input load of 10k or greater.
Most amplifiers are set at 18k or higher.
Ideally the amp would have an infinite impedance so as to draw no current from the source.
However can ignore this when driving it from a cd player, pre-amp or any other low impedance or buffered source. If you are connecting something like a microphone or a passive pre-amp then it is best not to have a low input impedance amp.
Input impedance is the impedance seen at the input of an item (could be a single stage or a whole piece of equipment). It forms a potential divider with the output impedance of whatever comes before it. Normally in audio we want input impedances to be significantly greater than output impedances, so there is little attenuation of the signal.
Note that there is some confusion about output impedance. You will often see people incorrectly calling the recommended load impedance the 'output impedance'. If a signal source (or preamp) says that it has an 'output impedance' of 10k then this either means they are confused (and really mean the load impedance should not be less than 10k) or the device is poorly designed and really does have such a high output impedance.
Note that there is some confusion about output impedance. You will often see people incorrectly calling the recommended load impedance the 'output impedance'. If a signal source (or preamp) says that it has an 'output impedance' of 10k then this either means they are confused (and really mean the load impedance should not be less than 10k) or the device is poorly designed and really does have such a high output impedance.
Thanks for the replies guys. @ John if you mean this - Input impedance > 4 K ohm ? thats exactly how its written in the manual i don't know what this means hence my original question.
No idea of the source output impedance ( Sony cdp 720 E QS )
No idea of the source output impedance ( Sony cdp 720 E QS )
Source output impedance for Sony CD player is less than 2k2. Input impedance > 4k makes little sense but should pose no issue with your CD player. I hope you have a volume control!
Could mean input impedance varies over a range of frequencies but is at least more than 4kohms. Unbuffered class D input stage can be weird.
Yes, ">4k" may imply something they don't want to draw attention to. Maybe a serious low pass filter giving significant capacitance at the input?
The amp is a Fatman Solid State S -60 i spent weeks trying to get info on it before buying including emailing all the addresses i could find for Fatman , T L audio and the distributor on the Fatman web site with no response . I couldn't find any information anywhere about topolgy etc other than the sparse details on the product page. i guessed it was class D but it sounds like could be a Tripath don't want to open at the moment and void warranty though. To be honest considering it's a ' lifestyle ' type product and the hype about " approaching the valve sound " in the sales blurb it sounds pretty good.
From what i read during my searching both TL and Fatman are listed as bankrupt and the distributor on the website ignores emails so unclear if still being made or they are just shifting old stock.
From what i read during my searching both TL and Fatman are listed as bankrupt and the distributor on the website ignores emails so unclear if still being made or they are just shifting old stock.
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