What would be the safest way to use a pair of Topping B100 as a headphone amplifier without losing signal quality?

[propaganda1]

Hello,

I know it sounds crazy but but speaker amps have been recommended in the past for very hard to drive/low impedance headphones, and I am very curious.

My setup would be Topping E70 -> 2 x Topping B100 -> Audeze LCD-5.

Is an XLR to banana plug cable all I'd need? I'd like to do this with zero affect on the audio signal of course.

What would the best way to keep the power to the headphones low (I'd need a miniscule amount of the usual output) other than setting them to low-gain? My nooby guess is using the E70 preamp but are there any other, more reliable ways?

Is there anything else I'd need to be aware of that I have not considered?

Thanks!

 

[propaganda1]

bump

 

[Redacted]

I wouldn't want to stick any phones on an amp's speaker output.

You say "My setup would be Topping E70 -> 2 x Topping B100 -> Audeze LCD-5." - does this mean you are thinking of buying these parts but don't have them yet?

At risk of being crucified as a heretic and a cloth-eared cheapskate, I'd avoid any boutique £4000 headphones, especially if they cannot be driven by a standard pre-amp headphone outputs. But you can probably find a headphone booster amp.

 

[Vincent Kars]

Audeze says the LCD-5 needs

Min recommended power	> 100mW
Recommended power level	>500mW

Max power handling

5W RMS

The B100 can produce 100 W into 4 Ohm.

Is there anything else I'd need to be aware of that I have not considered?

Yes, don't make this type of completely idiotic combinations because you have read something somewhere.

 

[Pow1]

Honestly the answer would to “what’s the safest way” to do that would be to avoid doing it.

For safety of both your equipment and your hearing too. Not to mention that the E70 uses digital volume control so if it glitches out for even a second and sends full power to the amp, you’ll destroy your equipment, your hearing, and possibly injure yourself too.

You mentioned that connecting headphones to speaker amps have been recommended back in the past. I’m curious as to how far back into the past you’re referring to.

My suggestion is to look at some of the highly rated headphone amplifiers here. Many of them should have sufficient power to drive your headphones to incredibly loud levels. But you can also verify yourself using those online calculators where you can put in a target listening level, the impedance and sensitivity of your headphones, and they’ll tell you how much power your amp needs to output to get to that target listening level.

 

[propaganda1]

I wouldn't want to stick any phones on an amp's speaker output.

You say "My setup would be Topping E70 -> 2 x Topping B100 -> Audeze LCD-5." - does this mean you are thinking of buying these parts but don't have them yet?

At risk of being crucified as a heretic and a cloth-eared cheapskate, I'd avoid any boutique £4000 headphones, especially if they cannot be driven by a standard pre-amp headphone outputs. But you can probably find a headphone booster amp.

Hi, thank you for your reply!

I currently own the LCD-5, and I really like them. I use an EQ with a huge bass boost (think Harman IE 2019) and a Dolby Atmos downmixer which results in a huge negative preamp (-30dB in the renderer) to avoid clipping (as a lot of Atmos content is very dynamic). A user with the same setup reported their amp (SMSL SH-9) going into protection during some scenes in movies (I think it was The Dark Knight) with the renderer active.

I also want to pickup a pair of Electrostatic headphones in the near future, and I've heard that a speaker amp + transformer is a viable way of powering them? I have no idea about anything to do with Electrostats so forgive my ignorance. It would be cheaper (I think) than having seperate amps for each headphone.

These factors is why I'm considering the speaker amp, but if you have other alternatives, please let me know!

 

[solderdude]

Imp = 14ohm
sensitivity = 108dB/V

This means to drive it loud (120dB peak) you need 4.5V in 14ohm

To do this with a power amp that is specified in 8ohm the amp needs to be 2.5W
When the amp is specified in 4ohm you need an amp that can provide 5W.
The B100 can reach 20V out !

As the driver is rated 5W (in 14 ohm) the max voltage should be 8V (= 9W in 8ohm) in which case it will produce an unhealthy 126dB.

As the B100 is differential out (bridged internally) you will need to use balanced cables on the LCD5.

For electrostatics get a good energizer with internal amp.

 

[Redacted]

Audeze says the LCD-5 needs

Min recommended power	> 100mW
Recommended power level	>500mW

Max power handling

5W RMS

The B100 can produce 100 W into 4 Ohm.

Yes, don't make this type of completely idiotic combinations because you have read something somewhere.

Well, I didn't check the specs. I missed out on the kind of dissing moment I enjoy! Ober da!

 

[Redacted]

Hi, thank you for your reply!

I currently own the LCD-5, and I really like them. I use an EQ with a huge bass boost (think Harman IE 2019) and a Dolby Atmos downmixer which results in a huge negative preamp (-30dB in the renderer) to avoid clipping (as a lot of Atmos content is very dynamic). A user with the same setup reported their amp (SMSL SH-9) going into protection during some scenes in movies (I think it was The Dark Knight) with the renderer active.

I also want to pickup a pair of Electrostatic headphones in the near future, and I've heard that a speaker amp + transformer is a viable way of powering them? I have no idea about anything to do with Electrostats so forgive my ignorance. It would be cheaper (I think) than having seperate amps for each headphone.

These factors is why I'm considering the speaker amp, but if you have other alternatives, please let me know!

I mostly like music over specs...

 

[Redacted]

Imp = 14ohm
sensitivity = 108dB/V

This means to drive it loud (120dB peak) you need 4.5V in 14ohm

To do this with a power amp that is specified in 8ohm the amp needs to be 2.5W
When the amp is specified in 4ohm you need an amp that can provide 5W.
The B100 can reach 20V out !

As the driver is rated 5W (in 14 ohm) the max voltage should be 8V (= 9W in 8ohm) in which case it will produce an unhealthy 126dB.

As the B100 is differential out (bridged internally) you will need to use balanced cables on the LCD5.

Careful with that axe Eugene, (or volume knob)

 

[solderdude]

With a 15ohm (10W) series resistance in series with each driver the B100 is safe to use (as in safe for the driver.... not so safe for the ears though).

Then again any headphone amp rated 1.5W in 16ohm is more than enough to driver the LCD-5 to uncomfortable loud levels.

 

[Redacted]

Then again any headphone amp rated 1.5W in 16ohm is more than enough to driver the LCD-5 to uncomfortable loud levels.

But can I literally melt my brain when I play my "Best of Abba" CD?

 

[solderdude]

It depends on how much you love ABBA I guess

120dB peak SPL is not the same as 120dBA average noise levels.
DR for best of ABBA ranges from 11 to 15 (track dependent)