[Articnoise]

I don't want to argue this so I will just say that I would not personally use a tube amp without a small resistor between the amp and headphone.

 

[Thenewguy007]

Has anyone actually tried it though?

 

[DuncanDirkDick]

I don't want to argue this so I will just say that I would not personally use a tube amp without a small resistor between the amp and headphone.

Funny, I wouldn't do that without a resistor between the taps. Just in case I pull the cable or something. But yes you can definitely do that.

 

[Nimzerz]

I've used my HE-500 with an MC240 with great results (other than some hum/noise floor, likely a ground loop involved) directly from the speaker taps

 

[Articnoise]

Funny, I wouldn't do that without a resistor between the taps. Just in case I pull the cable or something. But yes you can definitely do that.

Yes you can and it will work fine with >80% of all tube amps. The problem is that I know of no way of foresee which are fine and which isn't.

 

[DuncanDirkDick]

Yes you can and it will work fine with >80% of all tube amps. The problem is that I know of no way of foresee which are fine and which isn't.

Please elaborate

 

[GOKYO]

Yes you can and it will work fine with >80% of all tube amps. The problem is that I know of no way of foresee which are fine and which isn't.

these are the tube amps i've used directly from speaker taps to headphones....cary 805c/vac 70/70/airtight atm 300....i've also used a threshold t-400 with hifiman he-6

i'm not trying to be disrespectful...just sharing my experiance

 

[Articnoise]

these are the tube amps i've used directly from speaker taps to headphones....cary 805c/vac 70/70/airtight atm 300....i've also used a threshold t-400 with hifiman he-6

i'm not trying to be disrespectful...just sharing my experiance

Yes, this is in line with what I said i.e most tube speaker amps can drive headphones without a small resistor between the amp and headphone. I would not however personally use a tube speaker amp without a small resistors between the amp and headphone thou. This because I have no way of knowing before testing which amps will work fine and which will not. If others want to drive their headphones from a tube speaker amps without putting resistors on the speaker taps - they can do that.

 

[Pashmeister]

I think I may have found probably the best way for me to use a 300b tube speaker amp for my Susvara / TC. Bringing my Susvara with me, I visited the shop of a tube amp master based here in Singapore. He’s been in the business for a long time (designer and creator of Leo Research amplifiers). I tried his class A, 300b speaker amp that came with Full Music 300b tubes. The amp itself is also a good size for the desk (approx 30x30cm). I guess unsurprisingly the 300b amp sounded very good with the Susvara. It was a pure speaker amp with no headphone output. After I tested it, he mentioned that he can customise the amp by adding a headphone XLR socket that can deliver the same amount of power as the speaker taps. He can likewise specify the headphone socket to be 60ohms to make it a perfect match to my Susvaras. The custom work can be completed in 2-3 days. It’s a 100 SG$ custom job which seems to be a very attractive option that I’m now seriously considering.

 

[DuncanDirkDick]

Yes, this is in line with what I said i.e most tube speaker amps can drive headphones without a small resistor between the amp and headphone. I would not however personally use a tube speaker amp without a small resistors between the amp and headphone thou. This because I have no way of knowing before testing which amps will work fine and which will not. If others want to drive their headphones from a tube speaker amps without putting resistors on the speaker taps - they can do that.

Why? I'd just like to understand your reasoning behind that.

 

[ThanatosVI]

I think I may have found probably the best way for me to use a 300b tube speaker amp for my Susvara / TC. Bringing my Susvara with me, I visited the shop of a tube amp master based here in Singapore. He’s been in the business for a long time (designer and creator of Leo Research amplifiers). I tried his class A, 300b speaker amp that came with Full Music 300b tubes. The amp itself is also a good size for the desk (approx 30x30cm). I guess unsurprisingly the 300b amp sounded very good with the Susvara. It was a pure speaker amp with no headphone output. After I tested it, he mentioned that he can customise the amp by adding a headphone XLR socket that can deliver the same amount of power as the speaker taps. He can likewise specify the headphone socket to be 60ohms to make it a perfect match to my Susvaras. The custom work can be completed in 2-3 days. It’s a 100 SG$ custom job which seems to be a very attractive option that I’m now seriously considering.

Shouldn't the headphone output impedance be ~8 Ohm for the Susvara so that it keeps the "ideal" damping factor of ~8?

Impedance matching between amp and headphone usually follows the Rule that you want 1/8th of your headphone Impedance as output impedance.

If the difference is even bigger it doesn't change much anymore.
If the difference is less you "Lose control" over the driver, resulting in a loss of subbass extension and a midbass hump for planars (maybe also loss of top end extension, not sure anymore)

For dynamic drivers the changes are more severe, those don't have flat impedance over the frequency response, so the effects on the sound are harder to predict

 

[GOKYO]

Yes, this is in line with what I said i.e most tube speaker amps can drive headphones without a small resistor between the amp and headphone. I would not however personally use a tube speaker amp without a small resistors between the amp and headphone thou. This because I have no way of knowing before testing which amps will work fine and which will not. If others want to drive their headphones from a tube speaker amps without putting resistors on the speaker taps - they can do that.

yes i appreciate your concern....but my experiance has been that it was not necessary with the amps i mentioned....just trying to contribute to the "knowledge base"
here....LOL...we all here for the same reason

 

[Pashmeister]

Shouldn't the headphone output impedance be ~8 Ohm for the Susvara so that it keeps the "ideal" damping factor of ~8?

Impedance matching between amp and headphone usually follows the Rule that you want 1/8th of your headphone Impedance as output impedance.

If the difference is even bigger it doesn't change much anymore.
If the difference is less you "Lose control" over the driver, resulting in a loss of subbass extension and a midbass hump for planars (maybe also loss of top end extension, not sure anymore)

For dynamic drivers the changes are more severe, those don't have flat impedance over the frequency response, so the effects on the sound are harder to predict

Thanks for sharing; this subject is still foreign language to me (and I’m new to the hobby) and I look forward to learning more. So I guess it means I need even lower Ohm for the headphone socket, and also why attaching my Susvaras into the 8ohm speaker taps sound very good. And when I get a custom XLR headphone socket it needs to also be ~8 ohms just like the speaker taps because apprently it shouldn’t match 1:1 of the Susvara’s 60ohm impedance. I hope I got that right!

 

[DuncanDirkDick]

More like 6 Ohm. The amp probably has 4 Ohm taps as well, at least they are common enough. Just use those

 

[ThanatosVI]

Thanks for sharing; this subject is still foreign language to me (and I’m new to the hobby) and I look forward to learning more. So I guess it means I need even lower Ohm for the headphone socket, and also why attaching my Susvaras into the 8ohm speaker taps sound very good. And when I get a custom XLR headphone socket it needs to also be ~8 ohms just like the speaker taps because apprently it shouldn’t match 1:1 of the Susvara’s 60ohm impedance. I hope I got that right!

The 8 Ohm taps are meant for 8 Ohm speakers, that does not mean that the output impedance is 8 Ohm.