dsnyder0cnn
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D30ProI am thinking of selling my beloved Chord Mojo ( I love this thing and how it sounds) and getting a remote Controlled dac and Preamp.
I owned better measuring dacs before , but unfortunately i liked the chord Sound Signature the most.
Do you have any recommendations for a good pairing , Topping E60 would bei the best choice?
what kind of headphones u have, that u r willing to attach them to speaker amp? have u tried that before with any of ur amps?Honest question: is it possible to run balanced headphones out from an power amp? I saw some people running headphones driven by the Benchmark amps. If so, could the E50 + PA5 be "more versatile / powerful" than the E50 + L50?
what kind of headphones u have, that u r willing to attach them to speaker amp? have u tried that before with any of ur amps?
I hate to bring this up again, but the PA5 does have a volume control…also, headphones generally have much higher impedance than speakers. If my math is right 48 watts into 8Ω is the same as 1.28 watts into 300Ω. Yes, that's a lot, but you don't have to turn the volume to 11!Only if you want to kill your headphones and potentially deafen yourself.
Old school integrated amps with headphone outputs do this all the time. Use a power metal thin film resistor divider from amp output to ground. This prevents max amp output of 68Vpp from blowing your cans. Assuming 6.8Vpp is ok make a circa 10:1 divider with say 47ohm and 4.7ohm 2W resistors in series. Connect 4.7ohm to ground and headphones to node between 47ohm and 4.7ohm. The amp sees a 51.7ohm load (no big deal) and cans never see more than 6.8Vpp. However, your amp output impedance is about 47ohm. But that’s not a big deal. You could make lower values like 22ohms and 2.2ohms. Be careful with DC offset though. This is DIY though so do so at your own risk of damaging headphones. The amp is so low noise you should not hear any hiss or noise.Honest question: is it possible to run balanced headphones out from an power amp? I saw some people running headphones driven by the Benchmark amps. If so, could the E50 + PA5 be "more versatile / powerful" than the E50 + L50?
DC OFFSET you said...?Old school integrated amps with headphone outputs do this all the time. Use a power metal thin film resistor divider from amp output to ground. This prevents max amp output of 68Vpp from blowing your cans. Assuming 6.8Vpp is ok make a circa 10:1 divider with say 47ohm and 4.7ohm 2W resistors in series. Connect 4.7ohm to ground and headphones to node between 47ohm and 4.7ohm. The amp sees a 51.7ohm load (no big deal) and cans never see more than 6.8Vpp. However, your amp output impedance is about 47ohm. But that’s not a big deal. You could make lower values like 22ohms and 2.2ohms. Be careful with DC offset though. This is DIY though so do so at your own risk of damaging headphones. The amp is so low noise you should not hear any hiss or noise.
You can also be brave and connect them directly if can verify that DC offset is not an issue. And your cans have separate cables for left and right. Cannot share a common ground as the amp is bridge tied load (meaning the “negative” is live at 1/2Vcc or 19vdc. ).
Be real careful with the volume knob and do not not plug. Also, some DACs have a pop in between tracks of sample rate changes. That’s a no no and will destroy your headphones.
There are also some commercially available products that do this too. They are impedance matching transformers.Old school integrated amps with headphone outputs do this all the time. Use a power metal thin film resistor divider from amp output to ground. This prevents max amp output of 68Vpp from blowing your cans. Assuming 6.8Vpp is ok make a circa 10:1 divider with say 47ohm and 4.7ohm 2W resistors in series. Connect 4.7ohm to ground and headphones to node between 47ohm and 4.7ohm. The amp sees a 51.7ohm load (no big deal) and cans never see more than 6.8Vpp. However, your amp output impedance is about 47ohm. But that’s not a big deal. You could make lower values like 22ohms and 2.2ohms. Be careful with DC offset though. This is DIY though so do so at your own risk of damaging headphones. The amp is so low noise you should not hear any hiss or noise.
You can also be brave and connect them directly if can verify that DC offset is not an issue. And your cans have separate cables for left and right. Cannot share a common ground as the amp is bridge tied load (meaning the “negative” is live at 1/2Vcc or 19vdc. ).
Be real careful with the volume knob and do not not plug. Also, some DACs have a pop in between tracks of sample rate changes. That’s a no no and will destroy your headphones.
48 clean watts. This thing will happily do nearly 100W at 10%THD, so 2.6W into your 300ohm HP.I hate to bring this up again, but the PA5 does have a volume control…also, headphones generally have much higher impedance than speakers. If my math is right 48 watts into 8Ω is the same as 1.28 watts into 300Ω. Yes, that's a lot, but you don't have to turn the volume to 11!
Because the benefit of class D is efficiency at the cost of complexity. When you only need to deliver <1W, then efficiency becomes pretty much irrelevant and it is cheaper to use simpler A or AB designs.Headphones from speaker amps is equally fun and dangerous. Gotta be real carful with it.
Edit: speaking of using the pa5 for headphones brings up a genral question. Why are there no class D headphone amps? (At least ive never heard of one)
Old school integrated amps with headphone outputs do this all the time. Use a power metal thin film resistor divider from amp output to ground. This prevents max amp output of 68Vpp from blowing your cans. Assuming 6.8Vpp is ok make a circa 10:1 divider with say 47ohm and 4.7ohm 2W resistors in series. Connect 4.7ohm to ground and headphones to node between 47ohm and 4.7ohm...
I doubt it - as far as I can see, that doesn't include the attenuation (voltage dropper) circuit. Just an output resistor. And in any case such a device would need to have different attenuation for different amp output powers.Is it possible to buy a commercial version of this?
Yeah that makes senseBecause the benefit of class D is efficiency at the cost of complexity. When you only need to deliver <1W, then efficiency becomes pretty much irrelevant and it is cheaper to use simpler A or AB designs.