AudioPower (DPA-400) Sound pressure improvements?

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sent you PM and email mate, i'm having troubles with my internet service provider, dont think my email got through, but see PM, or perhaps if you send me an email I will be able to reply without being refused. new amp is looking good mate, the DXA has always looked interesting, you got around the issue preventing sale by changing design a bit?
Hi, i'm back on line just from 2 hours,(3 days of black-out ,same AP) maybe not send email for my troubles..ahah!
For DXA,i have changed modulator (job already done on the series DPA-xx),just for a choice without smps on board.
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you changed your icon.... now yes!, uh .. where did you hide the claws? :)

regards
 
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For this, we have resolved in some other way.
Sorry for OT:
We are awaiting the arrival of a new module (without smps on board). so we can offer this new + DPS-500 (goes very well at 110Vac) or you can power with transformer (if you think it's better).
As new DPA-series, this module is an exact copy of our DXA-600. only changes the modulator (in part). if you look carefully the section "Amp" of DPA-400/600 with DXA, see exactly the same, including chip and layers.
I show that this is the new DXA (not self Oscillating), as a section of the DPA-xx. qty printed and full test are ready, it should be available in 30 days...hope! :)

P.S. version present on site, is not this new version.

Regards

Any ETA on these modules less SMPS section and will there be bundle pricing with DPS-500 ?
 
Any ETA on these modules less SMPS section and will there be bundle pricing with DPS-500 ?
long absent hehe!
sorry, i think this is OT.
the characteristics are identical to F3. I think the cost Boundle, a few tens of dollars more, in comparison to 'F3, already in incredible low price, considering that it is not a PA amplifier.
F3 or dxa, we are ready to make any comparison with mono-block class AB, with 1KVA toroidal in side.
Today, in this chaotic market, there are no words to describe really a product. even a simple class D chip, it says "amazzing, nice, transparency, etc. .." but when I listen to them in testing (with low impedance high fidelity speaker), just turn up the volume on female vocals, with bass, throw it out the window. it seems that there vocals as digitized flute!...intermodulated by bass.

One new...F1 Tower (2xF1 vertical frame) just near our big speaker :)

Regards
 
long absent hehe!
sorry, i think this is OT.
the characteristics are identical to F3. I think the cost Boundle, a few tens of dollars more, in comparison to 'F3, already in incredible low price, considering that it is not a PA amplifier.
F3 or dxa, we are ready to make any comparison with mono-block class AB, with 1KVA toroidal in side.
Today, in this chaotic market, there are no words to describe really a product. even a simple class D chip, it says "amazzing, nice, transparency, etc. .." but when I listen to them in testing (with low impedance high fidelity speaker), just turn up the volume on female vocals, with bass, throw it out the window. it seems that there vocals as digitized flute!...intermodulated by bass.

One new...F1 Tower (2xF1 vertical frame) just near our big speaker :)

Regards

Hi Roberto!

Interesting research MDI team and you are doing. Thanks for sharing.

As for DPA-400/F-3 less SMPS section. What is the nomenclature of it IE what is it called?

Curious of pricing as the DPS-500s are about 200 Euro each and F-3 is 290 Euros so you're saying this module will be under a 100 Euros?

Basically we are talking 150-200 Euro a channel right?

So that's about $250-300 USD a channel. Not bad.

Sure would be great to have a single PCB module for NA 120V like the F-3 as this is going to add a lot more cost than just 10-20 Roberto. It's also nice to have the frame etc and those binding posts look nice on F-3.

Do we have anybody review F-3 yet? Sure would be great to hear second hand opinions of it's performance and sonic signature.
 
long absent hehe!
sorry, i think this is OT.
the characteristics are identical to F3. I think the cost Boundle, a few tens of dollars more, in comparison to 'F3, already in incredible low price, considering that it is not a PA amplifier.
F3 or dxa, we are ready to make any comparison with mono-block class AB, with 1KVA toroidal in side.
Today, in this chaotic market, there are no words to describe really a product. even a simple class D chip, it says "amazzing, nice, transparency, etc. .." but when I listen to them in testing (with low impedance high fidelity speaker), just turn up the volume on female vocals, with bass, throw it out the window. it seems that there vocals as digitized flute!...intermodulated by bass.

One new...F1 Tower (2xF1 vertical frame) just near our big speaker :)

Regards

So you guys work with an Italian PA equipment/design house? Can you share photos of these rigs?


Can you share the types and driver counts etc on loudspeakers driven with these digital amps?

Considering the cost per channel curious of active DSP xover systems you guys might be using in proaudio segment.

Thanks for sharing your work here Roberto.

Best regards.
 
Hi roberto.

On this topic, you wrote that DPA-400-F3 is 30mm high but on the mechanical sheet I read 40mm???
Hi, yes I wrote (ref to pcb), mean that height of complete pcb is 31,6mm.
F3 is complete of alluminum frame and heatsink, then consider 5mm spacers (include mylar isolation at bottom) and 2mm thick aluminum, we have total 40mm (if necessary, the dpa-400 can be mounted in 37mm height, including the spacers 5mm.).
DPA-400/F3-F2, fits perfectly in 1U.

Regards
 
Thank's. Do you have the datasheet ready?
Hi,
I apologize and take this opportunity to put this information on connecting to the connector 10Pin, maybe it can help you prepare for your connections. to complete the datasheet, I need this weekend.
some pasienza, I did not expect this huge demand, the next batch is already engaged. while waiting for the public review of F1.
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the DPA-400/Fx allows you to use the 10Pin connector with flat cable up to 40cm in length, inside the case, with absolutely no noise.
this is ensured, not only by the shielding provided by the frame, but by a careful development of the signals in use, especially in the section. power supply.
I recommend not to remove the frame, the amplifier has passed the test of RFI / EMI, with the lowest emissions obtainable.

Regards
 

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Any news of the datasheet Roberto?
Hi,
Just today i finish last measures also in smps section of DPA-400-xx,
then, some special measure (not standard), i show in this thread.
I think AP send you in 2 days.
NOTE:
becouse we started with F1, this have height >40mm, (heatsink use with 40mm), now F3 assemble new heatsink 36mm height. (your products have already this new) then, total height is 36mm+2mm base panel.;)
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I think that today, the best choice for a fan is to have an integrated amplifier, especially if it has been developed with the care necessary to achieve the performances, as a audiophile expect.
Given that a separate psu, is not a simple choice, judging by the noise problems that some diy complain. (with competitors smps..eheh)
To this is added, the result obtained without a fast voltage regulation.
Many diy, do not seem to understand, tons of work, research and development also of custom transformer, to obtain a total absence of noise, RFI included. but this is life!:)

Regards
 
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Yes, I totally agree.
Much of my time was spent on the comparison result in high Fidelity room. (this is my feedback with the development), my goal was when some audiophili mature, tried this amp (without knowing that it was a class D). compared with 30Kg class AB, all connected to professional loudspeaker with very low load.

Is easy to understand the limitations of an amp's with jazz and symphonic orchestra. if you set the volume at 70% power.
many class D amp's, already falls on the female voice and cimbals.
With the symphony, is immediately out the deficiency of the psu or turn down the volume ... hehe.
 
Hi,
Sorry for "OT"
Official release of DPA-400/F-3 (AP have not update photos)

Atoluma: this is your version.

PS. Coming soon measure (standard/ extended), some according thread title.
thank at all for patience

Regards
Roberto
 

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Hi, for now just a fft at 3w and 60w (4R).
DPA-400/F-3 connected direct on analyzer without filter.
Please, watch the segment 100Hz to 1kHz too.
without this cleaning harmonics, I can not put a smps in a good amplifier.
combined with the fast response, this amplifier is able to offer new performances, immediately listenable than another amplifier with smps, or linear power supply.
We have no doubt that this is a new real direction, instead of ultra low thd.
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The audio system of perception (ears + brain) is very sensitive to the geometry of the sound. because we use it to recognize sounds.
If I add a lot of treble on the sound of the snare drum, I am not able to disguise, everyone recognizes the snare.
same if I add 1% thd. but if haughty the geometry of only 0.4%, we perceive immediately that the musical instrument is changed. the geometry of the envelope sound defines the dynamic structure and consequently, the harmonic content.
Everything is so clear and perfectly repeatable in the lab, I do not understand why so many still insist with the linear power supply without fast regulation.
The circuits that stabilize the working point (in AB class) or a pseudo PSRR in D class, are not designed to respond to changes in the transients, are designed for DC or vs. the temperature.

The smps integrated in this amplifier is unique in the world a this moment.
like it or not, this is a truth!

regards
 

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Hi all.
Full activity is restored by the end of February. I refer to the new office, websites and all shipments suspended.
Unfortunately there have been some coincidences as the radical change of AudioPower (location and type of product).

Email are connected only for AudioPower (info,sales,support).
The Technical Support group works.

Best Regards
Roberto
 
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