This is a review, listening tests and detailed measurements of the Eleven XIAudio Broadway balanced battery operated desktop headphone amplifier. It is on kind loan from a member and costs US $2,599.
As you see, the unit only supports balanced headphone output. The volume control has excellent, fluid feel that is superior to many other implementations out there. And the knurled engraving on it helps with gripping it. Back panel shows balanced only input connection as well:
As noted, the unit sports a set of batteries internally which can power the unit for a few hours. As such, the power switch is momentary to turn the unit on and off. Being class A, the box uses fair bit of power and stays warm to touch, partially defeating the feature of battery operating it.
I like the choice of Meanwell power supply which is a nice brand of switching supplies.
What I absolutely did not like where the corners and edges of the unit. They are extremely sharp! I almost got a "paper cut" from just picking it up! They should be sanded to be smoother.
Testing proved challenging as the unit was very prone to ground loops when using my standard headphone load box. The loadbox has a power supply to operate its relays and was causing sever ground currents and reducing measured performance. I had to jump through a few loops to get around this. When using normal headphones, there is no power supply involved so you should not see this impact. Then again, something is causing this leakage which I usually don't see to this degree.
Another thing I didn't like was the gain switches: they are underneath the unit. If you only have one headphone, that is not so bad but if you have multiple, it is a pain to keep flipping the unit to change gain. And with those sharp edges, the hassles becomes twice as much!
XI Audio Broadway Measurements
I first tested the unit using high gain and with AC power:
I then unplugged the AC cable and it made no difference:
I then switched to low gain and was surprised that the SINAD reversed for each channel and there was clear output mismatch now:
Something is not right in low gain mode.
Anyway, the performance is good enough but nothing competitive to headphone amplifiers at a quarter of its price:
Baseline noise level was also too high:
So best to not use it with sensitive IEMs:
Perhaps realizing this, the company has a lower grain version of the unit.
Frequency response is excellent:
Let's measure power into 300 ohm:
300 milliwatts should be enough to drive just about every high impedance headphone to pretty loud levels (my minimum standard is 100 milliwatts). Distortion though sets in pretty early and clearly no match for state of the art headphone amplifiers.
Since I could not use my loadbox, I had to resort to my older passive balanced load which was at 25 ohm, not the usual 32:
Very strange distortion mechanisms there with those twists and turns before eventual clipping. I ran the unit on battery for both of the above measurements and the lines completely landed on top of each other indicating there is no noise or distortion difference.
Channel balance test was bamboozled by immediately channel offset which exceeded my 0.5 dB deviation:
High gain was better (not shown) but then again, you use low gain when you care about channel balance.
XIAudio Headphone Amplifier Listening Tests
I started my testing using my everyday Dan Clark Stealth headphone which is low impedance and requires a lot of power to drive. At reasonable volumes, the sound was good and no different than any other performant headphone amplifiers. As I cranked up the volume though, I started to hear a strange modulation of high frequency notes. It would elongate these notes as if put through a synthesizer! Push it a bit more and you had clear distortion and as such, unlistenable. Mind you, you were pretty much at the upper end of what you could tolerate as far as loudness.
Things improved -- as they usually do -- when the more sensitive Sennheiser HD650 headphone was put to task. There was ample volume and good sound to be had. Push some more though, and distortion clearly set in.
With neither one of these headphones did I notice anything extra fidelity in lower volumes when distortion was not present.
For comparison, I plugged both headphones into my reference Topping A90 headphone amplifier on my desk. The A90 pushed the Stealth to far, far higher loudness level, eventually causing the left channel driver to tick. There was no hint of distortion. We are talking a large gulf in loudness level between the A90 and Broadway. Same situation existed with the HD650 were the A90 was out to take prisoners, pushing it to levels of loudness which could cause near instant hearing loss!
Conclusions
Other than channel balance in low gain, the Broadway headphone amp has good enough performance both in distortion and power levels. As such, it can provide satisfactory experience with many headphones. Its battery operation is novel if you have a scenario where you want to lug such a large box around for portable use. Compared to other headphones amplifiers though, its performance falls short quite a bit including in available power and headroom. Its class A operation wastes power but doesn't bring anything as much as fidelity. So good enough if you have it, but nothing you want to go and buy especially at this price.
I can't recommend the Eleven Audio XIAudio Broadway headphone amplifier. There are so many better choices out there if you don't need battery operation.
As you see, the unit only supports balanced headphone output. The volume control has excellent, fluid feel that is superior to many other implementations out there. And the knurled engraving on it helps with gripping it. Back panel shows balanced only input connection as well:
As noted, the unit sports a set of batteries internally which can power the unit for a few hours. As such, the power switch is momentary to turn the unit on and off. Being class A, the box uses fair bit of power and stays warm to touch, partially defeating the feature of battery operating it.
I like the choice of Meanwell power supply which is a nice brand of switching supplies.
What I absolutely did not like where the corners and edges of the unit. They are extremely sharp! I almost got a "paper cut" from just picking it up! They should be sanded to be smoother.
Testing proved challenging as the unit was very prone to ground loops when using my standard headphone load box. The loadbox has a power supply to operate its relays and was causing sever ground currents and reducing measured performance. I had to jump through a few loops to get around this. When using normal headphones, there is no power supply involved so you should not see this impact. Then again, something is causing this leakage which I usually don't see to this degree.
Another thing I didn't like was the gain switches: they are underneath the unit. If you only have one headphone, that is not so bad but if you have multiple, it is a pain to keep flipping the unit to change gain. And with those sharp edges, the hassles becomes twice as much!
XI Audio Broadway Measurements
I first tested the unit using high gain and with AC power:
I then unplugged the AC cable and it made no difference:
I then switched to low gain and was surprised that the SINAD reversed for each channel and there was clear output mismatch now:
Something is not right in low gain mode.
Anyway, the performance is good enough but nothing competitive to headphone amplifiers at a quarter of its price:
Baseline noise level was also too high:
So best to not use it with sensitive IEMs:
Perhaps realizing this, the company has a lower grain version of the unit.
Frequency response is excellent:
Let's measure power into 300 ohm:
300 milliwatts should be enough to drive just about every high impedance headphone to pretty loud levels (my minimum standard is 100 milliwatts). Distortion though sets in pretty early and clearly no match for state of the art headphone amplifiers.
Since I could not use my loadbox, I had to resort to my older passive balanced load which was at 25 ohm, not the usual 32:
Very strange distortion mechanisms there with those twists and turns before eventual clipping. I ran the unit on battery for both of the above measurements and the lines completely landed on top of each other indicating there is no noise or distortion difference.
Channel balance test was bamboozled by immediately channel offset which exceeded my 0.5 dB deviation:
High gain was better (not shown) but then again, you use low gain when you care about channel balance.
XIAudio Headphone Amplifier Listening Tests
I started my testing using my everyday Dan Clark Stealth headphone which is low impedance and requires a lot of power to drive. At reasonable volumes, the sound was good and no different than any other performant headphone amplifiers. As I cranked up the volume though, I started to hear a strange modulation of high frequency notes. It would elongate these notes as if put through a synthesizer! Push it a bit more and you had clear distortion and as such, unlistenable. Mind you, you were pretty much at the upper end of what you could tolerate as far as loudness.
Things improved -- as they usually do -- when the more sensitive Sennheiser HD650 headphone was put to task. There was ample volume and good sound to be had. Push some more though, and distortion clearly set in.
With neither one of these headphones did I notice anything extra fidelity in lower volumes when distortion was not present.
For comparison, I plugged both headphones into my reference Topping A90 headphone amplifier on my desk. The A90 pushed the Stealth to far, far higher loudness level, eventually causing the left channel driver to tick. There was no hint of distortion. We are talking a large gulf in loudness level between the A90 and Broadway. Same situation existed with the HD650 were the A90 was out to take prisoners, pushing it to levels of loudness which could cause near instant hearing loss!
Conclusions
Other than channel balance in low gain, the Broadway headphone amp has good enough performance both in distortion and power levels. As such, it can provide satisfactory experience with many headphones. Its battery operation is novel if you have a scenario where you want to lug such a large box around for portable use. Compared to other headphones amplifiers though, its performance falls short quite a bit including in available power and headroom. Its class A operation wastes power but doesn't bring anything as much as fidelity. So good enough if you have it, but nothing you want to go and buy especially at this price.
I can't recommend the Eleven Audio XIAudio Broadway headphone amplifier. There are so many better choices out there if you don't need battery operation.
