Review and Measurements of Purifi 1ET400A Amplifier

[HionHiFi]

I love the case for this build! Anyone have a link for it?

I second @Pillars request?

 

[myblues]

Does anyone have experience in standard mode vs. low-gain mode? Does it have audible benefits?
I tried with my VTV Eval1 amplifier today. I'm using it with SMSL SU-8 v2. The DAC should be set to volume 14 (max is 40) in standard mode, and around 23 to have similar volume. So there's no headroom problems.
But it sounds more mellow and mid focussed in low-gain mode (with higher DAC volume) but again, i have no idea if this is placebo and if it has any real audible benefits.

 

[Rottmannash]

Does anyone have experience in standard mode vs. low-gain mode? Does it have audible benefits?
I tried with my VTV Eval1 amplifier today. I'm using it with SMSL SU-8 v2. The DAC should be set to volume 14 (max is 40) in standard mode, and around 23 to have similar volume. So there's no headroom problems.
But it sounds more mellow and mid focussed in low-gain mode (with higher DAC volume) but again, i have no idea if this is placebo and if it has any real audible benefits.

What is standard gain mode? What is low gain mode? And how are you changing the gain??

 

[Dundas]

What is standard gain mode? What is low gain mode? And how are you changing the gain??

See page 8 on the EVAL1 user guide.
https://purifi-audio.com/eigentakt/eval1/

 

[Rottmannash]

See page 8 on the EVAL1 user guide.
https://purifi-audio.com/eigentakt/eval1/

So you're unsoldering these resistors?

 

[Dundas]

So you're unsoldering these resistors?

No, change the jumpers marked FE Gain on page 3 as shown at the top of page 8. They are red for 1 channel and blue for the other and are next to the XLR jacks. Check the picture on the VTV web page:
https://vtvamplifier.com/product/vtv-amplifier-purifi-eigentakt-stereo-amplifier-based-on-eval-1/
Still easier said than done on an assembled amplifier.

 

[myblues]

What is standard gain mode? What is low gain mode? And how are you changing the gain??

You can change with the jumpers inside.

No, change the jumpers marked FE Gain on page 3 as shown at the top of page 8. They are red for 1 channel and blue for the other and are next to the XLR jacks. Check the picture on the VTV web page:
https://vtvamplifier.com/product/vtv-amplifier-purifi-eigentakt-stereo-amplifier-based-on-eval-1/
Still easier said than done on an assembled amplifier.

It was pretty easy though, just removing the screws on chassis and changing the jumpers, less than 5 min job.
But with low-gain mode (which shows better SINAD) it was more bass boomy and less clear. I wonder how others experienced.

 

[JimB]

You can change with the jumpers inside.


It was pretty easy though, just removing the screws on chassis and changing the jumpers, less than 5 min job.
But with low-gain mode (which shows better SINAD) it was more bass boomy and less clear. I wonder how others experienced.

If true, objectively, it could mean a limit in ability of the source to drive it, properly.

 

[myblues]

If true, objectively, it could mean a limit in ability of the source to drive it, properly.

That is true. There was plenty of headroom for volume though. (The dac needed about half way volume to have decent listening volume in low gain mode) I havent checked how low the input impedance go in low-gain mode. Maybe it's because of not being able to drive it regardless of volume.

 

[JSmith]

SINAD

I must have been reading ASR too much... was walking along the street today and a courier was unpacking his van. I swear I saw on a box SINAD... but on closer inspection it was something completely different.

I think I might get a tea cup or coffee mug with SINAD on it @amirm ... or even better would be one with the ASR logo with just "SINAD" in bold letters underneath, or maybe even "have you checked your SINAD?".



JSmith

 

[JimB]

I must have been reading ASR too much... was walking along the street today and a courier was unpacking his van. I swear I saw on a box SINAD... but on closer inspection it was something completely different.

I think I might get a tea cup or coffee mug with SINAD on it @amirm ... or even better would be one with the ASR logo with just "SINAD" in bold letters underneath, or maybe even "have you checked your SINAD?".



JSmith

Or "Do You Know Your SINAD?"

 

[formdissolve]

I've dug through a lot of the posts on here, but I suck at figuring out actual watt usage. I don't listen loud, so how would I calculate power usage in watts from these modules in EVAL1 form with stock Hypex PSU based on the specs? I'd listen at 25-40% of max output at the most (my speakers are 8 ohm 97dB sensitive so they don't need much power).

 

[JimB]

Unimaginable that they will not have enough power for you. Or are you concerned about power use from the mains? If so, the idle power is <20 watts. From there, add about 10% of whatever power your speakers are drawing.

 

[formdissolve]

Unimaginable that they will not have enough power for you. Or are you concerned about power use from the mains? If so, the idle power is <20 watts. From there, add about 10% of whatever power your speakers are drawing.

Yeah sorry I meant power draw from the wall. Not totally concerned since I know Class D amps will be much lower than my current one. Mostly just curious. Thanks for the response!

 

[Descartes]

So are there anyone else besides NAD and Nord that make amplifiers with Purifi 1ET400A?

 

[tmtomh]

So are there anyone else besides NAD and Nord that make amplifiers with Purifi 1ET400A?

https://www.audiosciencereview.com/...mplifier-sonic-shootout-€820-to-€8-344.14048/

 

[Rottmannash]

So are there anyone else besides NAD and Nord that make amplifiers with Purifi 1ET400A?

VTV.

 

[Descartes]

VTV.

Are they any good?

 

[Rottmannash]

Are they any good?

The one I have is flawless.

 

[Descartes]

The one I have is flawless.

How long have owned it for?