New world of HiFi with Chinese Class D Amps.

[P.M.B.66]

This subject seems to create lot of love and hate debate. Class D so cheap yet very good sound. The imperfect circuitry also gives the hobby a new flavour from rolling Op Amps. These small Amps now are very powerful. We have these on Dual-Mono Configuration, Bridged and Bi Amping power hungry floor Speakers. We power front and rear from two separate Amps. Single Amps are rated 300W x 2 with max power supply.

I have two Aiyima A07 Premium's with 48V 10A power and Op Amped High with opa1612 and Low with opa2134. These are Bridged and Bi Amped to drive Magnat Vector Needle floor Speakers and Audio Out has Magnat Alpha A30 active Subwoofer.

How do you find these cheap Class D amps? In my opinion having a great sound has become affordable to everyone.

Have you got some extreme setups?

Did you hear any difference between different power supplies? My opinion is that power is the most important for these Amps.

Do you use any EQ's and what DAC or Preamp are you using? I have Schiit Lokius EQ in my system and two different DAC's and Preamps wired to the system Main DAC is Schiit Mimir and from Jotunheim 3 output to A07 Premium. Secondary DAC/Headphone Amp/Preamp is Aiyima DAC A3 that has everything connected to it but it is an afterthought for the Sennheiser HD515 that has good surround sound for movies. Jotunheim 3 mainly is for music with HD600 Balanced.

I personally find tinkering around these cheap Amps enjoyable.

Aiyima A07 Premium.

 

[Enophile]

Such a great topic!

I think of these babies as a killer ‘first watt’ experience. They can have exceedingly clean and clear first watts!

I’ve got an SMSL, an Aiyima, and Fosi amps.

Matched with high sensitivity speakers, they can be lovely.

They are also essentially free!

Anyone interested in the ‘playing’ aspect of playback owes it to himself/herself to spend a little time with some!

Thanks for the topic!

 

[tadawson]

Looks like the power rating is typical fiction that seems all too normal for offshore class D stuff, and it doesn't make it to 20KHz, but fair overall.

AIYIMA A07 TPA3255 Review (Amplifier)

This is a review and detailed measurements of the AIYIMA A07 desktop amplifier based on TPA3255 class D amplifier chip. It was kindly purchased new by a member and drop shipped to me. The cost is US $72 on Amazon including prime shipping. And as of this shipping, it also included a 32 volt, 5...

www.audiosciencereview.com

 

[P.M.B.66]

Looks like the power rating is typical fiction that seems all too normal for offshore class D stuff, and it doesn't make it to 20KHz, but fair overall.

AIYIMA A07 TPA3255 Review (Amplifier)

This is a review and detailed measurements of the AIYIMA A07 desktop amplifier based on TPA3255 class D amplifier chip. It was kindly purchased new by a member and drop shipped to me. The cost is US $72 on Amazon including prime shipping. And as of this shipping, it also included a 32 volt, 5...

www.audiosciencereview.com

He is all about preaching numbers because he is hearing impaired and can't hear the differences. I wouldn't take that forum very seriously because audiophile is much more than just numbers where almost everything makes a difference for the sound while numbers stay the same.

 

[Enophile]

Looks like the power rating is typical fiction that seems all too normal for offshore class D stuff, and it doesn't make it to 20KHz, but fair overall.

AIYIMA A07 TPA3255 Review (Amplifier)

This is a review and detailed measurements of the AIYIMA A07 desktop amplifier based on TPA3255 class D amplifier chip. It was kindly purchased new by a member and drop shipped to me. The cost is US $72 on Amazon including prime shipping. And as of this shipping, it also included a 32 volt, 5...

www.audiosciencereview.com

It is down less than 1 dB at 20 KHz.

 

[tadawson]

It is down less than 1 dB at 20 KHz.

Which is at least 1db more than just about anything else, and the actual power output is crap vs. the adverspam

He is all about preaching numbers because he is hearing impaired and can't hear the differences. I wouldn't take that forum very seriously because audiophile is much more than just numbers where almost everything makes a difference for the sound while numbers stay the same.

And no, that's "audiophool" . . . ignoring hard data in favor of fantasy . . .
. . .

 

[P.M.B.66]

Which is at least 1db more than just about anything else, and the actual power output is crap vs. the adverspam

And no, that's "audiophool" . . . ignoring hard data in favor of fantasy . . .
. . .

So what does your system include?

 

[DesertRatt]

I had a pair of Aiyama A08 amps a couple years ago driving my 3 way open baffle speakers. They were every bit as good sounding as my Adcoms, and Carver amps. If they were down -1dB at 20KHz who the hell cares? That has at least a 50-50 chance of being an improvement for the speakers!

I also thought they were made really nicely. Clean design, good looking chassis very functional access and controls. I think they were under a $HUN. Ridiculously cheap.
I'm tempted to say they probably achieved the point of diminishing returns for spending more than that.

 

[P.M.B.66]

I had a pair of Aiyama A08 amps a couple years ago driving my 3 way open baffle speakers. They were every bit as good sounding as my Adcoms, and Carver amps. If they were down -1dB at 20KHz who the hell cares? That has at least a 50-50 chance of being an improvement for the speakers!

I also thought they were made really nicely. Clean design, good looking chassis very functional access and controls. I think they were under a $HUN. Ridiculously cheap.
I'm tempted to say they probably achieved the point of diminishing returns for spending more than that.

I was looked at the prices for A08 that were around $140. I don't know if that included the power supply. They were good but today in few years I see all of the brands that do Class D amps have got so much better in a very short time. And cheap with a sound that will make any audiophile weep that owns vintage +$5000 A/AB systems. We are living a time where good sound is at everyone's reach.

 

[tadawson]

So what does your system include?

Main is a Carver 4000 pre, two rebuilt (not modified) Phase Linear 400 S2, a Crown D75 as a headphone amp. Tascam CD-450 Pro CD machine, Technics SL2000 (iirc) w/ Ortofon 2M Bronze, Revox B710 cassette, a and Carver TX11 tuner. Speakers are EV Sentry-5 studio monitor for mains, and EAW UB-12se for rears. Oh, and an Audio Control C101 EQ. Tuning is done vith SMAART and a calibrated mic w/USB-Pre2 for a baseline. Thinking about adding Klipsch Forte IV's, but have not yet gotten drunk enough to justify the $$$.

I also have a live rig which is EAW and Crest, with a Soundcraft Analog mixed.

Surround system is EAW w/Klipsch sub, and a Lexicon DC-2 processor.

Note the lack of shady (offshore) brands (some will $h1t on Carver - get over it . . . found a clean one cheap, and have wanted one since 1980 . . .), and the tendency toward pro gear, where the specs aren't utter bull$h1t (and it's built to be serviceable). And, to that end, I have service manuals for just about everything I have (and the rest are simple enough to not need them).

Overall, my goal is a baseline signal path that has the "coloration" of wire . . . .

 

[Apreggiator]

I had a handful of SMSL's in the 'tripath' era. Some went up in smoke, two are still doing fine but I don't use them at the moment. ta2020 or ta2024 iirc?
I have and use two little bluetooth Chinese D-class bluetooth amps for my home made boomboxes, a 2.1 ZK-MT21 and a mono ZK1001-B. These are powered using a power tool battery.
The MT21 sounds acceptable-ish, the MT1001 sounds okay enough. But both have audible artifacts if you get the gain staging wrong (i.e. turn up the amp all the way, and the source down.
Bluetooth works surprisingly well and the "bluetooth device is-a connected successefullay" lady seems to be retired nowadays.
All in all not bad for 10-ish bucks amps. I do disconnect the battery when not in use as I have trust issues stemming from the smoke monster that visited some of my earlier SMSL's (okay, and one Lepai).

So I enjoy my 'low end' class d, but compared to my old little TEAC ah500i all the above pales in comparison. The added expense of op-amp rolling would have me look at products higher up the scale in the D class domain to be honest. I suspect something like a Topping PA-5 would serve me very well indeed.
And looking even further, there are products like Topping's D90, B100 and B200, which perhaps can be seen as the high-end of Chinese Class D, but I haven't had (enough) time with them to form an opinion. I find these interesting.

P.s. Not Chinese, but SE Asian Class D: I've used more Malaysian built Class D than Chinese, as that's where Hypex modules are actually produced (even though their HQ is in the Netherlands).

P.p.s; It's fun running efficient speakers with flea powered amps!

 

[P.M.B.66]

Main is a Carver 4000 pre, two rebuilt (not modified) Phase Linear 400 S2, a Crown D75 as a headphone amp. Tascam CD-450 Pro CD machine, Technics SL2000 (iirc) w/ Ortofon 2M Bronze, Revox B710 cassette, a and Carver TX11 tuner. Speakers are EV Sentry-5 studio monitor for mains, and EAW UB-12se for rears. Oh, and an Audio Control C101 EQ. Tuning is done vith SMAART and a calibrated mic w/USB-Pre2 for a baseline. Thinking about adding Klipsch Forte IV's, but have not yet gotten drunk enough to justify the $$$.

I also have a live rig which is EAW and Crest, with a Soundcraft Analog mixed.

Surround system is EAW w/Klipsch sub, and a Lexicon DC-2 processor.

And here you are arguing about Class D amps for example Aiyima A07 Premium $55. I also have more expensive stuff but hardly never gets used anymore because of the $55 stuff.

 

[Apreggiator]

And here you are arguing about Class D amps for example Aiyima A07 Premium $55. I also have more expensive stuff but hardly never gets used anymore because of the $55 stuff.

Good for you!

 

[tadawson]

And here you are arguing about Class D amps for example Aiyima A07 Premium $55. I also have more expensive stuff but hardly never gets used anymore because of the $55 stuff.

No, I'm arguing about dog$h1t offshore junk with fiction based specs . . . Cost is pretty much a non-factor, since most of this stuff was bought "hurt" and I restored it at trivial cost. The EV's were factory blems (paint . . . on the *back* . . .), the C101 bought with dead caps, one PL400 bought utterly "goobered" (about $60 to restore) the other bought used in 1985, recapped "just because" (all tested good, butndid add $.10 mod to eliminate possibility of latchup), seller of the C4000 thought it had a problem - none found . . . Bought the TT from a club ages ago for a song when MI went to 21 legql age, and they dumped thier music stuff . . . CD's bought used, replaced belts to fix loading issues . . . Heck, the only thing I bought new in that system was the TX11 . . .

And I *CAN afford most anything . . . I *choose* to not buy gear with, for exqmple, an actual $500 cost and a $4500 "bull$h1t upcharge" . . . (hence considering the Forte's . . . no room for Cornwalls . . . but the Sentry-V's continue to be amazing . . .)

 

[Apreggiator]

Oh I forgot to add, I do still want to try a couple of of different TPA3255 boards, can be found starting around 25ish on the well known Chinese marketplaces iirc.
I mention this^ because if you look at prices of the lower D class tiers, if you look beyond brand and a casing, the amp boards a lot of them are based on are even cheaper or you can get more for the same outlay...
This supplyer also has some interesting (to me at least) D class amp boards: Tinysine (Tinyos) Electronics

 

[P.M.B.66]

I had a handful of SMSL's in the 'tripath' era. Some went up in smoke, two are still doing fine but I don't use them at the moment. ta2020 or ta2024 iirc?
I have and use two little bluetooth Chinese D-class bluetooth amps for my home made boomboxes, a 2.1 ZK-MT21 and a mono ZK1001-B. These are powered using a power tool battery.
The MT21 sounds acceptable-ish, the MT1001 sounds okay enough. But both have audible artifacts if you get the gain staging wrong (i.e. turn up the amp all the way, and the source down.
Bluetooth works surprisingly well and the "bluetooth device is-a connected successefullay" lady seems to be retired nowadays.
All in all not bad for 10-ish bucks amps. I do disconnect the battery when not in use as I have trust issues stemming from the smoke monster that visited some of my earlier SMSL's (okay, and one Lepai).

So I enjoy my 'low end' class d, but compared to my old little TEAC ah500i all the above pales in comparison. The added expense of op-amp rolling would have me look at products higher up the scale to be honest. I suspect something like a Topping PA-5 would serve me very well indeed.
And looking even further, there are products like Topping's D90, B100 and B200, which perhaps can be seen as the high-end of Chinese Class D, but I haven't had (enough) time with them to form an opinion. I find these interesting.

P.s. Not Chinese, but SE Asian Class D: I've used more Malaysian built Class D than Chinese, as that's where Hypex modules are actually produced (even though their HQ is in the Netherlands).

P.p.s; It's fun running efficient speakers with flea powered amps!

$10 and sound comes out. I think money well spend. $55 for the Aiyima A07 Premium plus power supply another $50 or so all up around $110 is bargain for the sound it gives out. Of course these are not perfect and op amps can make a difference. The whole point of the post is to show how little you need to spend for good sound today. I have a full Pioneer system also that wasn't cheap at the day. But it hardly gets any use anymore. The cheap audio is taking over.

 

[Apreggiator]

$10 and sound comes out. I think money well spend. $55 for the Aiyima A07 Premium plus power supply another $50 or so all up around $110 is bargain for the sound it gives out. Of course these are not perfect and op amps can make a difference. The whole point of the post is to show how little you need to spend for good sound today. I have a full Pioneer system also that wasn't cheap at the day. But it hardly gets any use anymore. The cheap audio is taking over.

Switch mode power in amplification was a game changer for sure.
20.000 watts from a 2U rackunit? Sure! Labruppen will happily sell you their 20K44 model slightly north of 11k. And you can find a much cheaper knockoff of their lower tier models from Sinbosen.
Point being: Power becomes cheap with switch mode power amplifiers (such as Class D).

Quality and proper product support don't come cheap though, just look at what the totl models from SMSL and Topping can do and what they cost.
Or what the likes of Purifi and Hypex are doing.

 

[red 111]

 

[P.M.B.66]

No, I'm arguing about dog$h1t offshore junk with fiction based specs . . . Cost is pretty much a non-factor, since most of this stuff was bought "hurt" and I restored it at trivial cost. The EV's were factory blems (paint . . . on the *back* . . .), the C101 bought with dead caps, one PL400 bought utterly "goobered" (about $60 to restore) the other bought used in 1985, recapped "just because" (all tested good, butndid add $.10 mod to eliminate possibility of latchup), seller of the C4000 thought it had a problem - none found . . . Bought the TT from a club ages ago for a song when MI went to 21 legql age, and they dumped thier music stuff . . . CD's bought used, replaced belts to fix loading issues . . . Heck, the only thing I bought new in that system was the TX11 . . .

And I *CAN afford most anything . . . I *choose* to not buy gear with, for exqmple, an actual $500 cost and a $4500 "bull$h1t upcharge" . . . (hence considering the Forte's . . . no room for Cornwalls . . . but the Sentry-V's continue to be amazing . . .)

So you have vintage garage sale stuff and like fixing it. You clearly have some distorted hate about Chinese "junk with fiction based specs" that sounds better. Have you ever seen an amp that actually do what the specs say? Not many of them no matter where they are made. I think it would be better that you keep on your lane and enjoy the vintage stuff and let others enjoy their Class D amps.

 

[onwardjames]

Because my man Pio1980 has likely passed into the next realm, I'll share what he told me once in private.

"I have many, many classic tube amps, lovingly restored, and yet, if not for the emotional attachment, I'd let them go. The ALLO Volt D gives me a sense of "there-ness" that is simply better, if I'm being honest."

This isn't word for word, but the meaning is there. Steve, I sure miss ya, buddy. You were an icon here, full of polite help and a font of hard-won knowledge.