[ken6217]

Yes. Very helpful. Thanks so much!

 

[dadracer2]

Yes. Very helpful. Thanks so much!

You are most welcome. I wish I understood more tech but here's a thing you might want to check. Take a look at the valve seats and see if they say "Full Music 300B/n" as that means they are the TJ Full Music valves which are very well regarded and not just cheap and nasty valves to keep the amp costs down! There are several version of the TJ FM 300B and the SE version seems to be one of the best around. So if you feel the urge to upgrade that might be the place to start as it should build on the basic character of the amp......maybe? Anyway let me know what you decide in case I want to copy you!!!

 

[ken6217]

The stock tubes say Full Music 300B/n.

I'll let you know what I decide on doing. Btw, if you haven't experimented with the 6SN7 tubes, try that. You get a bigger difference in changing these out than the 300b tubes.

 

[dadracer2]

Thanks yes I wondered about those. Probably cheaper too!

 

[Andykong]

I would like to use my preamp, the Rogue Audio RP-7, as the source input to the HA-300. I want to avoid having to physically swap interconnects on my DAC every time I switch between using the HA-300 and my power amp. The preamp allows me to switch between outputs at the push of a button. Before I try this, would like to find out whether it is safe to do so given that the RP-7 has quite a lot of gain (20db via XLR). Would there be issues (safety or otherwise) with connecting my preamp to the HA-300?

To help, these are the specs for the RP-7:
- Tube complement: 4 x 12AU7/ECC82 tubes
- Frequency response: 1Hz – 100KHz +/- 1 dB
- THD: <0.1%
- Gain line stage: 14 dB (20dB XLR)
- Rated output: 1V
- Maximum output: 30V
- Output impedance: <10 Ohms

Appreciate any advice I can get on this.

The maximum output of RP-7 is 30V, that is quite a lot when compare to the standard XLR line output of DAC (4V in general).

However, this is maximum output only, I don't suppose you'll turn up the volume kof your RP-7 to maximum even with your speaker. So its a matter of setting the volume (or output) of your PR-7 to an appropriate level when you use it as the source of your HA-300. I recommend the following procedure to determine the suitable volume setting of PR-7

1. Connect your DAC to HA-300, preferably in XLR, plug in your favourite (and most familiar) headphone.
2. Play some familiar tune and set the volume to your preferred level.
3. Keep the volume level and setting of HA-300, turn it off, and now connect the DAC to PR-7, and then connect PR-7 to HA-300 in XLR.
4. Turn the volume of PR-7 to 0, power on the PR-7 and HA-300.
5. Play the same music files/CD again and gradually turn up the volume of PR-7 until you reached the same sound level from your headphone. This is one of the potential volume setting of PR-7 when serve as source of HA-300. Make sure you don't change anything on the HA-300 during the test.
6. Now repeat the process with a different headphone, and arrived at the second set of potential volume setting of PR-7.
7. If these two setting is vastly different, you might need to repeat the test with more headphones. Otherwise you can use the mean of the two potential volume setting as your final volume setting when connect PR-7 to HA-300

 

[GuyForkes]

The maximum output of RP-7 is 30V, that is quite a lot when compare to the standard XLR line output of DAC (4V in general).

However, this is maximum output only, I don't suppose you'll turn up the volume kof your RP-7 to maximum even with your speaker. So its a matter of setting the volume (or output) of your PR-7 to an appropriate level when you use it as the source of your HA-300. I recommend the following procedure to determine the suitable volume setting of PR-7

1. Connect your DAC to HA-300, preferably in XLR, plug in your favourite (and most familiar) headphone.
2. Play some familiar tune and set the volume to your preferred level.
3. Keep the volume level and setting of HA-300, turn it off, and now connect the DAC to PR-7, and then connect PR-7 to HA-300 in XLR.
4. Turn the volume of PR-7 to 0, power on the PR-7 and HA-300.
5. Play the same music files/CD again and gradually turn up the volume of PR-7 until you reached the same sound level from your headphone. This is one of the potential volume setting of PR-7 when serve as source of HA-300. Make sure you don't change anything on the HA-300 during the test.
6. Now repeat the process with a different headphone, and arrived at the second set of potential volume setting of PR-7.
7. If these two setting is vastly different, you might need to repeat the test with more headphones. Otherwise you can use the mean of the two potential volume setting as your final volume setting when connect PR-7 to HA-300

Thanks for the helpful advice Andy! Will try it this evening

 

[project86]

My review of the HA-300 is (finally) complete - take a look if you are interested. I know a growing number of folks in this thread already own the amp but at least there are pretty pictures to view.....

I agree with the past few pages where folks called out the imaging, layering, etc as particularly noteworthy. But it's hard to keep up with all the things this amp does well.

 

[westyjeff]

Nice review, great pictures, looks like the one on my desk!

 

[ken6217]

Great review. Too bad you didn’t have the Empyrean at the time you did the review.

I don’t find the same problem that you did with the volume control. I play music between 11 and 12 o’clock on mine. There were others on this thread that said similar as well.

 

[project86]

Yep, I've realized that my hearing is super sensitive and thus I prefer lower levels than most people around here. It's a blessing and a curse....

 

[ken6217]

Your comment about the gain however was mentioned in another review as well.

 

[project86]

As much as my hearing is admittedly sensitive, I do think the HA-300 should have the ability to go lower in volume. With HD660S or K812 (among others) there's just no way to listen at quiet levels. It comes on with moderate volume and ramps up quickly from there.

And yeah, I can make it work, but someone in the mood for quieter listening with those headphones would be out of luck if their source doesn't have volume control. Jazz and classical works better but a lot of modern music is already really hot in the mix anyway, which doesn't help.

I just think the top 5-10 volume steps (out of 24) are unlikely to be useful for most people, outside of maybe Susvara or HE6 type headphones. And there's a gain switch as well... so I would expect a full range from "barely audible" to "way too loud". And HA-300 does not accomplish that.

Again, nitpicking a bit.... but something to be aware of.

 

[westyjeff]

After your comment about the K7XX I had to get mine out and turn up some Van Halen,,,,,,,Damn forgot how good these are with a little bass added. Hot for Teacher !!

 

[ken6217]

I just think the top 5-10 volume steps (out of 24) are unlikely to be useful for most people, outside of maybe Susvara or HE6 type headphones. And there's a gain switch as well... so I would expect a full range from "barely audible" to "way too loud". And HA-300 does not accomplish that.

I find it odd that your amp plays this way and I play mine at approx 50% up in the volume knob,
even taking into account volume preferences. My DAC outputs 4V which is pretty standard.

 

[westyjeff]

I find it odd that your amp plays this way and I play mine at approx 50% up in the volume knob,
even taking into account volume preferences. My DAC outputs 4V which is pretty standard.

I felt the same about this comment, my volume is plenty low at one or two clicks, progressivly louder untill 12 which is high, but thats where I like it. Impedance at M.