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View Full Version : About to replace Hifiberry DAC/Cambridge Azur 340a with Hifiberry AMP2 - Thoughts?



toplard
2018-04-26, 12:18
Hi All,

Anyone have anything to say about this upgrade?

Current setup is excellent. Only problem is the traditional old amp is too large.

For example, what about sound quality of the Amp2 - can anyone testify for it?

The Cambridge is 50W output which is less than the new Amp2.

I'm thinking, if I eliminate the analogue cable between old DAC and old amp that will improve sound?

I only listen to FLAC locally and streamed.

Any thoughts. And apologies if this should be in Audiophiles.

Cheers.

Mnyb
2018-04-26, 12:38
These small class D amps they usually bend the specifications into to pure fantasy. Your old Cambridge is large for a reason.
It produces 50 “real Watts “ room size and speakers and listening habits predict your amplifier needs too .

A 5 watt direct from internet class d chip amp is usually sold as 20-30 watt depending on how they spec .

toplard
2018-04-26, 13:19
These small class D amps they usually bend the specifications into to pure fantasy. Your old Cambridge is large for a reason.
It produces 50 “real Watts “ room size and speakers and listening habits predict your amplifier needs too .

A 5 watt direct from internet class d chip amp is usually sold as 20-30 watt depending on how they spec .


Please define "real watts". And how do they differ from 'unreal' or "small class" watts?

Jeff07971
2018-04-26, 15:09
Please define "real watts". And how do they differ from 'unreal' or "small class" watts?

As Mnyb says
These small class D amps they usually bend the specifications into to pure fantasy.


Real Watts = CONTINUOUS RMS Watts

https://en.wikipedia.org/wiki/Audio_power

See "Measurements"

You'd be mad to replace the Azur with the AMP+

Jeff

See AMP+ Specs :-

UP TO 25W output power
CAPABLE of driving 4 Ohm speakers (also works with higher impedance speakers)

No other Specs, Get the picture ?

Mnyb
2018-04-26, 21:40
A real measurement is usually 20hz-20kHz continues at speced distortion say 0,01% both channels driven at the same time.
At 8ohms speaker impedance .

These 25 watts can be peak short term at 1khz 1% distortion at 4 ohm .

Some even add the 2 channels together to have more “watts” ?

If you can’t find better specs , look at the power adapter/wallwart for a clue divide by 4 for a ballpark figure.

Mnyb
2018-04-26, 21:48
But it’s probably not bad for what it is :) they do sell it with a 60 watt power adapter .

Some other users here know more about chip amps , some are well regarded , again for what they are .
Think small speakers not that loud . You can probably design a very nifty squeezebox multiroom solution with this .

toplard
2018-04-27, 03:53
Jeff, See title. I'm talking about the AMP2 not the AMP+, which was know to have weaknesses.

Still none the wiser. Are there any experts you know who can help please?


As Mnyb says


Real Watts = CONTINUOUS RMS Watts

https://en.wikipedia.org/wiki/Audio_power

See "Measurements"

You'd be mad to replace the Azur with the AMP+

Jeff

See AMP+ Specs :-

UP TO 25W output power
CAPABLE of driving 4 Ohm speakers (also works with higher impedance speakers)

No other Specs, Get the picture ?

toplard
2018-04-27, 03:57
But it’s probably not bad for what it is :) they do sell it with a 60 watt power adapter .

Some other users here know more about chip amps , some are well regarded , again for what they are .
Think small speakers not that loud . You can probably design a very nifty squeezebox multiroom solution with this .

The 60W adapter is because its 60W potential output - for the AMP2

If you look carefully at the specs it tells you what it'll do per adapter used. They're not marketing it like the common audiophile prefers.

I've already tried with a small UK mini amp supplier. And this was not satisfactory so I returned it.

I'm going to have a stab at it with a 24V adapter and see how it fares. I'll report back below.

Mnyb
2018-04-27, 04:09
The 60W adapter is because its 60W potential output - for the AMP2

If you look carefully at the specs it tells you what it'll do per adapter used. They're not marketing it like the common audiophile prefers.

I've already tried with a small UK mini amp supplier. And this was not satisfactory so I returned it.

I'm going to have a stab at it with a 24V adapter and see how it fares. I'll report back below.

I think the rating is 12-18 volt supply I would not go over that .

What kind of speakers ore we trying to drive ?

Jeff07971
2018-04-27, 04:43
Jeff, See title. I'm talking about the AMP2 not the AMP+, which was know to have weaknesses.

Still none the wiser. Are there any experts you know who can help please?


Sorry my bad, still same applies

Specs for the TAS5756M are here http://www.ti.com/lit/ds/symlink/tas5756m.pdf

Power Output 28W/ch @ 8Ohms @ 24V
Power Output 20W/ch @ 4Ohms @ 24V

Azur 340A 40W/ch @ 8ohm, 50W/ch @ 4Ohms

Jeff

Mnyb
2018-04-27, 04:45
Sorry my bad, still same applies

Specs for the TAS5756M are here http://www.ti.com/lit/ds/symlink/tas5756m.pdf

Power Output 28W/ch @ 8Ohms @ 24V
Power Output 20W/ch @ 4Ohms @ 24V

Azur 340A 40W @ 8ohm, 50W @ 4Ohms

Jeff

Very good with the chip known , you can get at something .
Wonder why hiffiberry limits the voltage and recomend 18v supply is to protect the pi itself ?

Jeff07971
2018-04-27, 05:13
Very good with the chip known , you can get at something .
Wonder why hiffiberry limits the voltage and recomend 18v supply is to protect the pi itself ?

Hifiberry seem to recomend 18v for both 4 and 8 ohm speakers (less than 18w/ch for both 4&8 Ohm) which is unusual, but maybe hifiberries thermal dissapption is compromised somehow.

Don't get me wrong, I like and use Class D(T) amps a lot and they're very good but I use larger ones (Hifimediy T2's mostly)

Still think this is a downgrade though but if size is the reason........

Jeff

toplard
2018-04-27, 10:15
I think the rating is 12-18 volt supply I would not go over that .

What kind of speakers ore we trying to drive ?

Mordaunt-Short 902i - so 8 ohm. Daniel of Hifiberry says 24v might be better but is not necessary. So I'll stick with their recommended adapter.

toplard
2018-04-27, 10:16
Hifiberry seem to recomend 18v for both 4 and 8 ohm speakers (less than 18w/ch for both 4&8 Ohm) which is unusual, but maybe hifiberries thermal dissapption is compromised somehow.

Don't get me wrong, I like and use Class D(T) amps a lot and they're very good but I use larger ones (Hifimediy T2's mostly)

Still think this is a downgrade though but if size is the reason........

Jeff

I'm expecting it to be worse too. And let's see how it plays out. I'll post it here.

Mnyb
2018-04-27, 20:58
Mordaunt-Short 902i - so 8 ohm. Daniel of Hifiberry says 24v might be better but is not necessary. So I'll stick with their recommended adapter.

Yes if read the TI paper on the chip it seems that voltage is the limit for higher impedance speakers .
And it’s current limited at lower impedance.
Not surprising.

Hopefully it performs “good enough” for the purpose .

My secondary system is probably worse , but fit for purpose , I’m using small active foster speakers to lessen the clutter .
( inspired by this I think I move my much better Adam speakers from the computer out there instead )

toplard
2018-04-28, 03:33
Sorry my bad, still same applies

Specs for the TAS5756M are here http://www.ti.com/lit/ds/symlink/tas5756m.pdf

Power Output 28W/ch @ 8Ohms @ 24V
Power Output 20W/ch @ 4Ohms @ 24V

Azur 340A 40W/ch @ 8ohm, 50W/ch @ 4Ohms

JeffGood hint on the Azur thx. Couldn't find that detail yet. Its on order with reco'd 18v PSU. So we'll see empirically (will try to be objective). BTW, using the Azur in my setup is uncomfortable over half volume on the amp control. Not sure if control is linear on volume or quality?

Sent from my VFD 900 using Tapatalk

Mnyb
2018-04-30, 02:29
Good hint on the Azur thx. Couldn't find that detail yet. Its on order with reco'd 18v PSU. So we'll see empirically (will try to be objective). BTW, using the Azur in my setup is uncomfortable over half volume on the amp control. Not sure if control is linear on volume or quality?

Sent from my VFD 900 using Tapatalk

Where the volume control is does not really say anything , it’s like in spinal tap where a guy has a guitar amp that goes to eleven instead of ten :) neither source output voltages or input sensitivity and gain is standardised .

IMO using more than half the volume knob is good the pot is more linear there , hence the azur could be sensible designed to not have to much gain ei you have to twiddle the knob more .
In practice most amp has to much gain so you don’t have as much margin as think , with a strong source it’s clips and misbehave long before you reach the and of the volume control .
To much gain is usually for two reasons people can have old analog sources with 0,25-0,5 volt output or less , think cassette deck old tuner vhs player . A CD or squeezebox is about 2,0 to 2,5 volt.
And it’s impressive to the noob in the shop when the amp is “loud” whit just a little bit of volume

kappclark
2018-04-30, 12:04
FWIW, I am using a Kinter MA-170 for my desktop ... says 2 x 18w ... ( $10.00 from parts express (https://www.parts-express.com/kinter-ma-170-2-channel-mini-amplifier-bass-treble-rca-in-2-x-18w--310-372) ! ) enough juice for the desktop ..

toplard
2018-05-05, 02:11
Here's a brief upshot of the AMP as a replacement for a Cambridge Azur 340A:

1) it certainly has enough volume, and gets uncomfortable in my room at 70%(Azur was 50%)
2) no definable difference in sound quality
3) it sounds subtly different in general, but too intangible to say

Result? I'm amazed. I cannot safely say the "watts" are worse than on the traditional Azur, with all due respect to you good folks commenting here. So much so that I don't think it necessary to revert to the old setup to re-test.

So go for it. My lounge looks that much the 'cleaner' for it - just speakers!

By all means be brutal with your questions and I'll go and test them.

BTW (on a tangent I've substituted Squeeze Commander for Squeezer, as my phone is now on secure BYOD. Pity, but Squeezer is good too. Wish Android had iPeng)

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