Bruno Strikes Again. Purifi 1ET7040SA VTV Amplifier.

[boXem]

I have the Eval 1. Wondering how much more oomph the new module will have? Appreciably more powerful, especially with my 4 ohm speakers? Worth the upgrade?

Since there seem to be some confusion around the power of these new modules, lets clarify a few things:
1. the 1ET400A power is limited by power supply rails voltage for loads above 3.3 Ohm.
2. the 1ET400A power is limited by its self-protection for loads below 3.3 Ohm.
3. the 1ET7040SA power is limited by power supply rails voltage for loads slightly above 2 Ohm.
4. the 1ET7040SApower is limited by its self-protection for loads below slightly above 2 Ohm.

This means that with an identical power supply, both 1ET400A and 1ET7040SA deliver the exact same power for loads above 3.3 Ohm
Any OEM using an Hypex power supply and selling more than 210W in 8 Ohm for either 1ET400A or 1ET7040SA is misleading at best.

Compared to the 1ET400A, the interest of these new modules is their ability to deliver huge amounts of current in very difficult loads. For more "normal" speakers, no notable difference.

 

[mrmojo2022]

Since there seem to be some confusion around the power of these new modules, lets clarify a few things:
1. the 1ET400A power is limited by power supply rails voltage for loads above 3.3 Ohm.
2. the 1ET400A power is limited by its self-protection for loads below 3.3 Ohm.
3. the 1ET7040SA power is limited by power supply rails voltage for loads slightly above 2 Ohm.
4. the 1ET7040SApower is limited by its self-protection for loads below slightly above 2 Ohm.

This means that with an identical power supply, both 1ET400A and 1ET7040SA deliver the exact same power for loads above 3.3 Ohm
Any OEM using an Hypex power supply and selling more than 210W in 8 Ohm for either 1ET400A or 1ET7040SA is misleading at best.

Compared to the 1ET400A, the interest of these new modules is their ability to deliver huge amounts of current in very difficult loads. For more "normal" speakers, no notable difference.

Interesting that VTV show on their website a Hypex 1200watt 64 volt psu powering a stereo 1et7040sa pair.

How is that psu meant to power 950watts per channel into 2 ohms?

 

[Derkkk]

Interesting that VTV show on their website a Hypex 1200watt 64 volt psu powering a stereo 1et7040sa pair.

How is that psu meant to power 950watts per channel into 2 ohms?

Count me in on this. I'm confused as well on the ratings. I really want to get Boxem Monos with the new amps but if they aren't going to benefit me in anyway for some 4ohm speakers then what's the point really. Id rather have the beautiful compact stereo unit he makes now. After looking at all the different companies BoXem by far fits my taste out of everyone else. Apollon looks great but little pricey for what I wanna have into it as Ive never heard a class D amp so no idea if Id like it.

 

[mrmojo2022]

Count me in on this. I'm confused as well on the ratings. I really want to get Boxem Monos with the new amps but if they aren't going to benefit me in anyway for some 4ohm speakers then what's the point really. Id rather have the beautiful compact stereo unit he makes now. After looking at all the different companies BoXem by far fits my taste out of everyone else. Apollon looks great but little pricey for what I wanna have into it as Ive never heard a class D amp so no idea if Id like it.

Spec sheet says its more powerful 500 watts 4 ohms but it won't do that with any of the existing Hypex PSUs. they are teither too low or too high voltage.
Many speakers drop below 4 ohms so the extra current is useful.
Smps1200 won't asequately power a pair of these modules.

 

[Derkkk]

Spec sheet says its more powerful 500 watts 4 ohms but it won't do that with any of the existing Hypex PSUs. they are teither too low or too high voltage.
Many speakers drop below 4 ohms so the extra current is useful.
Smps1200 won't asequately power a pair of these modules.

Do you think or has it been discussed that Purifi will make their own PSU's? Maybe because of the specs of this amp they'll make their own PSU's finally? I'm Also curious if running two of the Hypex PSU's would solve this but sounds like it wont. Then there is other companies using traditional power supplies like ATI does. Otherwise I guess just getting the current AMP that's out will suffice.

 

[boXem]

Do you think or has it been discussed that Purifi will make their own PSU's? Maybe because of the specs of this amp they'll make their own PSU's finally? I'm Also curious if running two of the Hypex PSU's would solve this but sounds like it wont. Then there is other companies using traditional power supplies like ATI does. Otherwise I guess just getting the current AMP that's out will suffice.

The amp module will work perfectly well with an Hypex PSU. It just won't have it's maximum power performance in everything stated as "voltage limited", whatever the amount or PSUs installed.

 

[boXem]

Smps1200 won't asequately power a pair of these modules.

For a stereo amp, an SMPS3k is needed. SMPS1200 is good for a mono one.

 

[Derkkk]

For a stereo amp, an SMPS3k is needed. SMPS1200 is good for a mono one.

So am I correct in saying there is no current PSU that will allow the new amp to run at its full potential? From what you said above about anything higher than 3.3ohms with an identical power supply between the two amps wont have a difference in power. So, is there any combination to get the most out of the new amp module? If the new Amp modules were setup in mono and each had their own SMPS 1200? Does it need more than this? Do you plan on working this out to get the most of the new amp module? Or will it be advertised as a "Buy this if your speakers need lots of current" Otherwise buy the current Amp modules by Purifi? Or am I just getting this all confused and for someone that has 4ohm speakers the new modules wont really benefit me in anyway.

 

[boXem]

So am I correct in saying there is no current PSU that will allow the new amp to run at its full potential?

There is no Hypex PSU with 70V rails. BTW, since the 1ET400A is specified with 65V rails, the Hypex PSUs with their 63V rails do not allow it to reach it's full potential either.

From what you said above about anything higher than 3.3ohms with an identical power supply between the two amps wont have a difference in power. So, is there any combination to get the most out of the new amp module? If the new Amp modules were setup in mono and each had their own SMPS 1200? Does it need more than this?

One SMPS1200 per module is my plan. Then the amps will be able to fully deliver their potential in difficult loads. They will miss about 50 W in higher loads, which is not such big deal since it is about 0.75 dB in 8 Ohm.

Do you plan on working this out to get the most of the new amp module?

Working this out would mean developing a power supply. Not for 0.75 dB

Or will it be advertised as a "Buy this if your speakers need lots of current" Otherwise buy the current Amp modules by Purifi?

That's a bit what I have been writing the other day isn't it?

Or am I just getting this all confused and for someone that has 4ohm speakers the new modules wont really benefit me in anyway.

If your speakers' impedance doesn't go below 4 Ohm I am not sure there is an interest for you going the 1ET4070SA route.

 

[Derkkk]

There is no Hypex PSU with 70V rails. BTW, since the 1ET400A is specified with 65V rails, the Hypex PSUs with their 63V rails do not allow it to reach it's full potential either.

Perfect! That makes way more sense to my head. Starting to get the picture now. I did not know this even about the 400 module.

One SMPS1200 per module is my plan. Then the amps will be able to fully deliver their potential in difficult loads. They will miss about 50 W in higher loads, which is not such big deal since it is about 0.75 dB in 8 Ohm.

Ahhhh not much at all.

Working this out would mean developing a power supply. Not for 0.75 dB

Dont blame you!

That's a bit what I have been writing the other day isn't it?

Yeah i see that now I just needed what you posted above. My brain wasn't processing it. Makes way more sense now.

If your speakers' impedance doesn't go below 4 Ohm I am not sure there is an interest for you going the 1ET4070SA route.

Noted. Maybe I'm crazy but now I feel like I don't have to wait for the new stuff and I really like the compactness of your current 400 stereo model.

 

[mrmojo2022]

Do you think or has it been discussed that Purifi will make their own PSU's? Maybe because of the specs of this amp they'll make their own PSU's finally? I'm Also curious if running two of the Hypex PSU's would solve this but sounds like it wont. Then there is other companies using traditional power supplies like ATI does. Otherwise I guess just getting the current AMP that's out will suffice.

I don't know. two psus won't solve the voltage problem. the closest hypex smps1200 is 63volt and 70 volt is required to get these modules to their 500 watt rating

 

[mrmojo2022]

There is no Hypex PSU with 70V rails. BTW, since the 1ET400A is specified with 65V rails, the Hypex PSUs with their 63V rails do not allow it to reach it's full potential either.

One SMPS1200 per module is my plan.

The March amp tested here reaches that spec with the Hypex supply, so there may be some latitude in the psu output voltage, but the required 7 volts extra for the 7040 is quit a lot.

 

[restorer-john]

Any OEM using an Hypex power supply and selling more than 210W in 8 Ohm for either 1ET400A or 1ET7040SA is misleading at best.

Have you measured the output voltage of the SMPS when powered from 220V EU or 240V (230V nom) as we have here in Aus? A recent test of such a product achieved 246wpc@8R in Australia.

 

[mrmojo2022]

So am I correct in saying there is no current PSU that will allow the new amp to run at its full potential? From what you said above about anything higher than 3.3ohms with an identical power supply between the two amps wont have a difference in power.

Depends on the impedance curve of your speakers. lots of nominal 4 ohm speakers dip way below this. what speakers are they? we might be able to find an impedance plot.

 

[boXem]

The March amp tested here reaches that spec with the Hypex supply


View attachment 182221

Performances from the second table are in typical operating conditions from first table.
+VP and -VP from the first table are 65V typ.

Have you measured the output voltage of the SMPS when powered from 220V EU or 240V (230V nom) as we have here in Aus? A recent test of such a product achieved 246wpc@8R in Australia.

It is 63V unloaded. Since it is an unregulated SMPS voltage is falling with load. Measuring all amps produced. Good ones deliver 220 W 8 Ohm, weak ones 210 W. I never ever saw one delivering 246 W in 8 Ohm. edit: (with 1% distorsion)

 

[mrmojo2022]

Performances from the second table are in typical operating conditions from first table.
+VP and -VP from the first table are 65V typ.

It is 63V unloaded. Since it is an unregulated SMPS voltage is falling with load. Measuring all amps produced. Good ones deliver 220 W 8 Ohm, weak ones 210 W. I never ever saw one delivering 246 W in 8 Ohm.

Independent test above shows the March doing so. It is close to double the 8 ohm measured performance. What are yours doing at 4 ohms?

 

[boXem]

Independent test above shows the March doing so.

No comment on this

Can we look at Amirs test of the 1et400?

Slightly above 200 W.

 

[mrmojo2022]

No comment on this

Slightly above 200 W.

He is on 110 volt supply though. I don't know how wel the Hyoex supplies regulate between their 110v and 240v settings.

 

[mrmojo2022]

Measuring all amps produced. Good ones deliver 220 W 8 Ohm, weak ones 210 W. I never ever saw one delivering 246 W in 8 Ohm. edit: (with 1% distorsion)

Erm you might want to revise your website claims in that case.

 

[restorer-john]

He is on 110 volt supply though.

The Australian HiFi test is on 230V nominal, likely 240V at the time of test. Our standard was 240V (and still sits at 240V). I'm currently sitting on 239V here. Steve Holding and "newport test labs" have no credibility here and never have had. Read the review- he thinks the 'noise floor' is 140dB down...

Clearly he hasn't heard of FFT gain when looking at his spectrum analyzer.

140dB is 10 million times. With respect to full power, that means a residual of 4uV. The Purifi is quiet, but it aint that quiet.