[dpump]

What are 2 tubes on the left side? Maybe voltage regulators? And the 2 input tubes? 12AU7 or something else?

 

[dadracer2]

What are 2 tubes on the left side? Maybe voltage regulators? And the 2 input tubes? 12AU7 or something else?

I think they could be power supply rectifiers and maybe are the RCA 22DE4, which is the one used on the HA300 for the same purpose.

 

[Matro5]

Very curious to see if this might also be used an amp, or a preamp...

 

[340519]

It looks beautiful.

 

[whirlwind]

This has my attention.

 

[Andykong]

Very curious to see if this might also be used an amp, or a preamp...

No speaker out or RCA/XLR output, straight forward headphone amplifier only.

 

[Andykong]

What are 2 tubes on the left side? Maybe voltage regulators? And the 2 input tubes? 12AU7 or something else?

Very good eyes, the input tubes are 12AU7. The two rectifier tubes on the left are 22DE4

 

[Andykong]

I think they could be power supply rectifiers and maybe are the RCA 22DE4, which is the one used on the HA300 for the same purpose.

Indeed, the HA-6A incurred a lot of elements from HA-300, you can even consider the chassis as a one-box scale-down version of HA-300, with the separated power supply merged with the amplifier chassis and then scaled down from 445mm (159 mm + 286mm in HA-300) to the current 360mm

 

[Andykong]

My PrimaLuna Dialogue Premium HP has the feature to change between Triode and Ultralinear on the fly. It is an integrated amp with headphones output same as the speakers output just reducing the power to fit headphones.
I actually use it exclusively for headphones.
It can also un EL34, EL77, KT88, KT120 and KT150.

But the Triode and Ultralinear mode only apply to the speaker output, the headphone output of the Dialogue Premium HP is not coming from the EL34 output, so not affected by the mode selection.

 

[Andykong]

Can you post a photo of the rear please? Just wondering if there will be speaker posts...........

I don't have a photo of the rear panel, but the following drawing should serve the purpose. There is no speaker output in the HA-6A.

 

[musicman59]

Do you own one? Have you listen to it and trying switching?
The headphones output is coming from the EL34 output. That’s the reason I bought it and use it as a tube headphones amplifier.
You can very clear hear out of the headphones the change in sound when you switch between the two modes.

 

[musicman59]

From the PrimaLuna website:
HEADPHONE AMPLIFIER
One of the best headphone amps in the world. And the only amp that lets you listen with either the warmth of Triode or the wide-bandwidth of Ultra-linear operation at the push of a button! Most tube integrated amps and preamps use a solid state op-amp chip for running headphones. Stand alone tube headphone amps will vary in quality like any other tube amp. Headphones are simply small speakers that require less power. Some amps will use smaller output tubes that groan to have enough dissipation to run power-hungry planar headphones. Other brands, including those costing $5,000 or more like Mal Valve, will use larger output tubes, then use a voltage divider network to drop the power down to an acceptable level for headphones. This is how PrimaLuna designed the HP. We simply took advantage of the fact that this is the best tube integrated amplifier. Now you don't have to pay for a separate state of the art headphone amp. The HP is the favorite of owners who use everything from Audeze to Hifiman to Sennheiser!

and as I said, one can clearly hear the difference through the headphones when switching between Triode and Ultralinera.

 

[dadracer2]

I don't have a photo of the rear panel, but the following drawing should serve the purpose. There is no speaker output in the HA-6A.

Thanks Andy. Shame about the speaker outs but I can see the strong family resemblance with the HA300.

 

[441879]

Sign me up. I’ve been looking at the HA-1A an HA-300 for a while now and this looks like what I’m seeking.

 

[Andykong]

From the PrimaLuna website:
HEADPHONE AMPLIFIER
One of the best headphone amps in the world. And the only amp that lets you listen with either the warmth of Triode or the wide-bandwidth of Ultra-linear operation at the push of a button! Most tube integrated amps and preamps use a solid state op-amp chip for running headphones. Stand alone tube headphone amps will vary in quality like any other tube amp. Headphones are simply small speakers that require less power. Some amps will use smaller output tubes that groan to have enough dissipation to run power-hungry planar headphones. Other brands, including those costing $5,000 or more like Mal Valve, will use larger output tubes, then use a voltage divider network to drop the power down to an acceptable level for headphones. This is how PrimaLuna designed the HP. We simply took advantage of the fact that this is the best tube integrated amplifier. Now you don't have to pay for a separate state of the art headphone amp. The HP is the favorite of owners who use everything from Audeze to Hifiman to Sennheiser!

and as I said, one can clearly hear the difference through the headphones when switching between Triode and Ultralinera.

I have consulted our Engineers regarding the TR and UL operation mode in more detail, and find out that Cayin MT-35MK2 and CS-55A (both EL34 version and KT88 version) are tube integrated amplifier with headphone output and TR/UL selection. The headphone output of these two integrated amplifiers are an attenuated output from speaker port directly, so the TR/UL selection will also affect the headphone output, theoretically they are also headphone output with TR/UL selection. However our Engineer consider these two integrated amplifier are speaker amplifiers primarily and the headphone output are not optimised other than attenuation, so they won't call these headphone amplifier technically, especially when compare to our HA-1A, HA-6A and HA-300 where we have impedance matching output to optimise the performance of headphone amplifier for wide range of headphones. We can't tell if the PrimaLuna has a designated headphone amplifier circuit speaker amplification. Maybe they have and that'll make them superior to the two examples I quoted.