[muths66]

I have a couple of those coming over on a slow boat from china... should be interesting with good opamps...

I have try my friend ss tungsten on a denon amp direct with cable and my ex he1000v2 too. tungsten just abit more volume in my speaker amp. Which have 50w@8ohm.Now i just wait for my ss tungsten and my gustard h26 amp to reach to try.

 

[muths66]

People need to be careful with this.

Class D amplifiers are not load invariant. This means that with higher than expected load impedances, they will behave abnormally.
The Fosi V3 for instance seems to be set up for 4 ish Ohm speakers. And even at 8 Ohm it's already over-amplifying high frequency content quite a bit, including quite significantly in the 30-50khz region



I'd be worried about what it's gonna do with a 150-300 Ohm load.......
At best it's going to colour things by boosting treble quite a bit. And at worst it could cause damage either to your hearing or your headphones if it's feeding high levels of ultrasonic content through them, and you wouldn't know it was happening

I am careful when using with speaker amp directly i fo have a cayin ha1a mk2 to use as a preamp too to add flavour to it.

 

[kehadnb94]

so no one got a frequency response chart??

 

[GoldenSound]

People need to be careful with this.

Class D amplifiers are not load invariant. This means that with higher than expected load impedances, they will behave abnormally.
The Fosi V3 for instance seems to be set up for 4 ish Ohm speakers. And even at 8 Ohm it's already over-amplifying high frequency content quite a bit, including quite significantly in the 30-50khz region



I'd be worried about what it's gonna do with a 150-300 Ohm load.......
At best it's going to colour things by boosting treble quite a bit. And at worst it could cause damage either to your hearing or your headphones if it's feeding high levels of ultrasonic content through them, and you wouldn't know it was happening

Did some quick maffs

Here's a simulation of a class D output filter with various loads. With a 155 Ohm load of tungsten, you could be creating a couple dB boost in the upper treble, with over TWENTY DB increase at 40khz.

L = 11.26uH
Cbtl = 0.703uF

I would not put headphones on a class-D amp without an impedance adapter, at best it's gonna colour things by boosting treble, and at worst could damage your hearing or headphones and you may not even realise it's happening

 

[Dixter]

loo

Did some quick maffs

Here's a simulation of a class D output filter with various loads. With a 155 Ohm load of tungsten, you could be creating a couple dB boost in the upper treble, with over TWENTY DB increase at 40khz.


L = 11.26uH
Cbtl = 0.703uF



I would not put headphones on a class-D amp without an impedance adapter, at best it's gonna colour things by boosting treble, and at worst could damage your hearing or headphones and you may not even realise it's happening

looks like a great dog caller..

 

[Dixter]

wish Zeos would come here and answer some of these questions .... he is using the amps and the tungsten here on this vid... ( time - 36:52)

 

[theangelboy]

Well, today I learned why there aren't class D headphone amps. LOL

 

[GoldenSound]

Well, today I learned why there aren't class D headphone amps. LOL

Yep, it's unfortunately quite tricky to make a class D amp that'd be suitable for the extremely wide range of impedances headphones are found in.
Though the other aspect is simply that given the relatively MUCH lower power that headphones need, the space/efficiency requirements of Class D aren't really much of a thing whereas in speaker amps that's definitely a big advantage.

 

[Knee Deep In Epoxy]

Did some quick maffs

Here's a simulation of a class D output filter with various loads. With a 155 Ohm load of tungsten, you could be creating a couple dB boost in the upper treble, with over TWENTY DB increase at 40khz.


L = 11.26uH
Cbtl = 0.703uF



I would not put headphones on a class-D amp without an impedance adapter, at best it's gonna colour things by boosting treble, and at worst could damage your hearing or headphones and you may not even realise it's happening

I had no idea inaudible ultrasonic sound can damage hearing.

Yet another thing to be paranoid about. No more screaming bats for me then. Thanks for nothing, Golden!

(But thanks, really).

 

[dl95]

https://hifi-express.com/products/sabaj-a20h-headphone-amplifier

Anyone have any thoughts on this amp? 1W at 300 ohms for an $109 amp seems very impressive. Very curious how much power it can put out at the 135-155ohms the SS/DS are at.

 

[muths66]

Another abit more ex budget driveable amp for tungsten i can think of is accurate a281.

 

[Menkau-ra]

Soncoz SGP1! Great looking (and sounding) amp. Which pre-amp are you using?

I'm using Wandla -> SGP1

 

[psy472]

For those trying to find cheaper amp alternative, please be careful of hearing loss from the speaker amp. Headphone breaking is fine as you can always get another one, but hearing loss is permanent.

 

[Dixter]

For those trying to find cheaper amp alternative, please be careful of hearing loss from the speaker amp. Headphone breaking is fine as you can always get another one, but hearing loss is permanent.

EQ is your friend... just setup the high freq filter and you won't have to worry about it or not... might be a good idea to set those for all amp/headphones... that way you are covered either way...

 

[goldwerger]

Bryan at Zynsonix also has a similar product. I didn’t try this one but used some other products he made and his work is good:

https://www.zynsonix.com/Speaker-Amp-to-Headphone-Converter-Box_p_36.html

(But when you introduce a resistor in the signal path, it loses some of the benefit of using a speaker amp to start with - I don’t think such products are needed for the Tungsten)