P452

Hi Dave

Sounds intriguing 🙂

We have a brand new PSU for the P422 which has been custom designed to our specification.

In a number of ways the old Hypex PSU is quite unsophisticated. One of the major issues is that its output voltage varies proportionally with the mains input voltage. So if your mains voltage goes below the nominal spec (which they often do) then the PSU output voltage also drops. This variable output voltage bad for a number of reasons, including leading to the amplifier not having high enough voltage to meet its power output spec. Our new PSU maintains output voltage regardless.

Our new PSU is also lower noise. It has larger output capacitors which reduce load dependant voltage modulation. Class D amps dont behave the same as class A or A/B amps when presented with highly reactive speaker loads. One great advantage is that they dont suffer the high power dissipations and produced heat that class A or A/AB do in this circumstance, but do suffer "bus pumping' where it makes the supply voltage vary. The larger caps in the new PSU mitigate and minimise this compared to the Hypex.

New supply has greater current output. It also is more efficient with power factor correction. The standby and control circuitry is also built into the supply where previously it was separate. The new psu has fully automatic mains voltage sensing to operate between 100v and 240v where the Hypex you have to select the high/low supply range with an internal jumper.

All our range of amplifiers now feature the new PSU. Its a great improvement over the Hypex.

Hope that helps

Alan

Oh dear - So the next question is are you upgrading the P452 power supplies?

The new power supplies will not fit in the older and smaller P452 cases, so we will not be offering an upgrade service. Please note there was a short crossover period (recent P452 orders) which used the new larger cases and PSUs and were labelled P452. If in doubt please contact us.

March Audio generally has the policy of continual improvement to products, so specs and designs will change over time. Whilst this design change is an improvement, it takes nothing away from the great performance of the older Hypex PSU based P452.

Another reason we needed to change the PSU was to service the new more powerful Purifi 1ET7040SA amp modules as used in our new P501 amp. These require a higher PSU voltage than the 1et400 in the p452/P422. Hypex do not offer a PSU with an appropriate voltage for these modules.

That's clear. Thanks Alan, I will send a direct email.

I suppose I got one of the transitional models. It has the larger case and ring-light power button but says P452 at the front. It also has the trigger port between the inputs and speaker posts, rather than more to the middle.

Curious to know if my P452 is one of the transition models as its case is 26cm deep & I think the original P452 was 20cm deep? Very happy with it in either case!

Michael wrote:
Curious to know if my P452 is one of the transition models as its case is 26cm deep & I think the original P452 was 20cm deep? Very happy with it in either case!

Hi Michael

Send me an email and we will check it out.

cheers

Alan

Hi Alan,

Is there plans to release the P422 with the Purifi 1ET7040SA unit?

Cheers
David M.

DMcInnes wrote:

Is there plans to release the P422 with the Purifi 1ET7040SA unit?

Wouldn’t that be a P502?

DMcInnes wrote:
Hi Alan,

Is there plans to release the P422 with the Purifi 1ET7040SA unit?

Cheers
David M.

Hi David

Not at the moment. TBH as either a physically larger 2.2kW PSU, or 2 of the monoblock PSUs would be required, we would have to have a larger case than the P422. So the pricing for a P502 wouldn't be far off a pair of monoblocks.

Secondly the potential maximum 20 amp mains current draw does start to become an issue in 110volt territories. Although it's very unlikely to occur with music as opposed to test signals.

Just be wary of some manufacturers trying to use Hypex smps1200a400 PSUs with the 1et7040sa. They are too low a voltage. You won't get the rated 500watts into 4 ohms.

Alan

Alan March wrote:
Hi David

Not at the moment. TBH as either a physically larger 2.2kW PSU, or 2 of the monoblock PSUs would be required, we would have to have a larger case than the P422. So the pricing for a P502 wouldn't be far off a pair of monoblocks.

Secondly the potential maximum 20 amp mains current draw does start to become an issue in 110volt territories. Although it's very unlikely to occur with music as opposed to test signals.

Just be wary of some manufacturers trying to use Hypex smps1200a400 PSUs with the 1et7040sa. They are too low a voltage. You won't get the rated 500watts into 4 ohms.

Alan

Hi Alan

My I ask a question?
Do you have any plan to use newer 1ET9040BA amps?
😉

thin bLue wrote:
Hi Alan

My I ask a question?
Do you have any plan to use newer 1ET9040BA amps?
😉

Hi @thin bLue

No plans as of yet. I saw and discussed the amp with Bruno when we met in Munich a few weeks back.

At the end of the day they will have very slightly more noise and distortion than the existing offerings. So my question is, do we really need more power? The 1et7040 in our p501 amp can deliver 500 Watts into 4 ohms and 950 Watts into 2 ohms.

There are very few domestic hifi speakers that can handle more than 500 Watts, so I see the market as very small for such an amplifier.

Alan March wrote:
Hi @thin bLue

No plans as of yet. I saw and discussed the amp with Bruno when we met in Munich a few weeks back.

At the end of the day they will have very slightly more noise and distortion than the existing offerings. So my question is, do we really need more power? The 1et7040 in our p501 amp can deliver 500 Watts into 4 ohms and 950 Watts into 2 ohms.

There are very few domestic hifi speakers that can handle more than 500 Watts, so I see the market as very small for such an amplifier.

I got it!

Thanks for confirm that!
I heard some rumors about 1et9040ba will have great power (same 40A as 1et7040, 1% thd 1500W @ 2Ohm) with lower noise of ~8 uV before.
But, as you confirmed, with slightly more noise, it looks we can only get marginal very gains with massive price increase can not be justified at this moment.

Maybe it'll fit for boutique amp made for multiple-8", 10" or larger- low-noise high xmax-Purifi-ed speakers for the future not now.😋

thin bLue wrote:
I got it!

Thanks for confirm that!
I heard some rumors about 1et9040ba will have great power (same 40A as 1et7040, 1% thd 1500W @ 2Ohm) with lower noise of ~8 uV before.
But, as you confirmed, with slightly more noise, it looks we can only get marginal very gains with massive price increase can not be justified at this moment.

Maybe it'll fit for boutique amp made for multiple-8", 10" or larger- low-noise high xmax-Purifi-ed speakers for the future.😋

When integrated with a buffer amp (remember you will need even more gain to achieve the higher output voltage to achieve the higher power output), its gain will increase the noise figure, so maybe not much difference. certainly not anything that has any real world relevance. All the Purifi amps are astoundingly quiet.

No power figures were confirmed, but considering the supply voltage I was quoted, your estimate of power seems about right.