Minidsp SHD Power Amplifier Review

[o2so]

i just installed it like 2 weeks ago

and you could see the SHD as a Roon end point without having to run Roon via Volumio?

 

[dougi]

Do they explain why they chose AES for digital out rather than SPDIF? Seems a strange choice in this segment. Clocking benefits in an active system?

 

[PeteL]

Do they explain why they chose AES for digital out rather than SPDIF? Seems a strange choice in this segment. Clocking benefits in an active system?

There is no clocking benefit, AES/EBU and spdif are identical signal in term of data. altouh you get the benefit of being balanced, so more imune to interference, and the characteristic impedance is different, and a flag bit difference. Technically you can convert one with the other, but I agree it’s not ideal when connecting consumer equipment.

 

[PresbyByrd]

This is an encouraging review. I have to think someone will develop a product that connects all these moving parts!

 

[snackiac]

I had been using this for a couple months before sending it in, and I am happy with it for the most part. The remote programming was an issue though, it does weird stuff with AppleTV remotes because it's auto programmed for them by default or something? Anyways, I was having an issue where I'd change the volume down and the input occasionally changes to LAN. Support was responsive at first but then disappeared. Enough clear/retries with various remote codes assigned to the Apple TV remote seemed to fix it, but just a mild warning.

 

[McFly]

BTW Amir, in the miniDSP plugin you can change a setting for the amplifier from 4 ohm mode to 8 ohm mode. This setting may be what caused your 8 ohm power output to be low.

Amp builders - what would this setting actually do?

 

[amirm]

BTW Amir, in the miniDSP plugin you can change a setting for the amplifier from 4 ohm mode to 8 ohm mode. This setting may be what caused your 8 ohm power output to be low.

I played with that but made no difference. I am not clear what it is supposed to do.

 

[sfdoddsy]

Interesting review as usual.

Especially interesting for me as I was beer browsing the other night and bought a pair of the MiniDSP PWR-Ice DSP amps.

They should have a better amp section than the SHD. Hopefully the preamp/EQ section is just as good.

 

[waynel]

I played with that but made no difference. I am not clear what it is supposed to do.

Probably just thermal protection settings

 

[somebodyelse]

Amp builders - what would this setting actually do?

In 3E's TPA3255 it changes the psu voltage. If I understood the explanation correctly the output power of the PSU is the limiting factor, so it can be set in a lower voltage, higher current configuration to suit the 4R load, or higher voltage, lower current to suit 8R.

 

[Snuggiefart]

I played with that but made no difference. I am not clear what it is supposed to do.

It can't be switching LC filter to better attenuate HF either for 4 ohm or 8 ohm speaker load, right?
TI has a whole document dedicated to LC filtering TPA amps, but that would probably require a separate set of components to be implemented in the MiniDSP and take a lot of space on the board.

 

[amirm]

It can't be switching LC filter to better attenuate HF either for 4 ohm or 8 ohm speaker load, right?

A relay would be expensive so I doubt it.

 

[landco]

My wish for minidsp is simple: offer a second unit with a Purifi amplifier module in it. And add Roon streaming.

Why Purifi? Texas makes great amplifiers. There are very competent engineers working in Texas and they perfectly understand that the parameters you tested are MUCH higher than the sensitivity threshold of any human ear.

 

[Ralferator]

The dirt-cheap Aiyima A07 -- a tiny power amp with a handy gain control -- is remarkably good if you team it with an adequate power supply. I use two of them in my system and subjectively they vastly outperform the highly acclaimed, Nelson Pass designed Adcom GFA-535 I swore by back in the day. Too bad I can't spare one of mine for Amir to test -- and of course he may well find measurable flaws that I can't hear if/when he gets his hands on one. I also understand that Allo has a TPA3255-based amp in the works, and given that those folks did such a good job with the much older, far less capable TPA3116 chip -- check out Amir's review -- I'm looking forward to what they come up with.

Do you use the Aiyima A07 with the original OP amps? Are they good sounding or did you put in other OP amps?

 

[Ron Texas]

Some thoughts here:
1. This is an all in one solution for a 2.2 system. I did not read the manual carefully, but it appears to take care of subwoofer integration.
2. It's on the expensive side for Chi-Fi
3. Some forum members have reported various problems with the MiniDSP SHD or Studio models not initializing properly.
4. 120 WPC isn't enough power for everyone.
5. SINAD while not state of the art, should keep noise and distortion at inaudible levels.
6. I'm not ordering one to replace my Crown XLS 1502 and Topping DX3 Pro which has a SINAD which is 10 db worse, but sounds good with LS50's and Rythmic L12 Subs.

 

[Bruce Morgen]

Do you use the Aiyima A07 with the original OP amps? Are they good sounding or did you put in other OP amps?

I've never even cracked open the cases of either of my A07s. Honestly, IMO the whole notion of "op amp rolling" is a waste of time, especially at the A07's price point -- again IMO, the audible performance differences between decent audio-specific op amps are minuscule. It's a rare recording studio mixing desk that doesn't include dozens of (now 30+-year-old) TI NE5532 op amp ICs, and the audio performance requirements of such an expensive piece of professional gear are far more stringent than what one can reasonably expect of a little sub-$50USD "chip amp."

 

[Ralferator]

I've never even cracked open the cases of either of my A07s. Honestly, IMO the whole notion of "op amp rolling" is a waste of time, especially at the A07's price point -- again IMO, the audible performance differences between decent audio-specific op amps are minuscule. It's a rare recording studio mixing desk that doesn't include dozens of (now 30+-year-old) TI NE5532 op amp ICs, and the audio performance requirements of such an expensive piece of professional gear are far more stringent than what one can reasonably expect of a little sub-$50USD "chip amp."

That's what i thought too but some people in this forum swear that the differences between op amps where huge and also they say that the OP amps in the Ayima A07 should be fakes. But it's good to hear, that you are satisfied. Since my speakers are not extremely bright sounding and not so revealing i think i should just stay with the original OP amps. Thank you!

 

[Bruce Morgen]

That's what i thought too but some people in this forum swear that the differences between op amps where huge and also they say that the OP amps in the Ayima A07 should be fakes. But it's good to hear, that you are satisfied. Since my speakers are not extremely bright sounding and not so revealing i think i should just stay with the original OP amps. Thank you!

Older op amps like the NE5532 are dirt cheap in OEM quantities -- so cheap that IMO it makes no sense for Aiyima to resort to counterfeits. That said, what folks hear is what folks hear, and if some of them find an op amp swap worthwhile, who am I to rain on their parades?

 

[Ralferator]

Older op amps like the NE5532 are dirt cheap in OEM quantities -- so cheap that IMO it makes no sense for Aiyima to resort to counterfeits. That said, what folks hear is what folks hear, and if some of them find an op amp swap worthwhile, who am I to rain on their parades?

I was wondering because there is a lot of talk about fake NE5532 op amps. I also think it doesn't make sense if they are so cheap. I know that when people put a lot of money in audio equipment they can hear all kinds of improvements.
I am also not going to judge them but when people talk about "huge" differences then i start to think that maybe it's worth it a try. But i guess it's the same as with speaker cables. Maybe they just listen more attentive when they got a new one or they move their head some inches forward and of course then the sound changes

 

[somebodyelse]

Older op amps like the NE5532 are dirt cheap in OEM quantities -- so cheap that IMO it makes no sense for Aiyima to resort to counterfeits. That said, what folks hear is what folks hear, and if some of them find an op amp swap worthwhile, who am I to rain on their parades?

Keep in mind that the OEMs aren't necessarily resorting to counterfeits - they can also be victims of a polluted supply chain.