@FSHZ42
AGD’s GaNFET amps do have at least one differentiator vs other GaNFET designs - Alberto (AGD’s principal) uses GaNFETs that were specifically designed for audio applications and for which he was (I believe) the team leader for the group developing them. Due to some corporate actions, he ended up buying the entire stock of these devices and uses them in his amps, so no other mfg has these particular parts.
There’s more to choosing the AGD Tempo than just sonics. Alberto designs all of his amps so they are easily upgraded by the user. I recognize this also provides him an ongoing income stream, but it also allows me to simply plug in a new output stage as he makes improvements to this part of the circuit. In his other (more expensive) designs, this takes on the look of a vacuum tube - simply plug and play. For the Tempo, you remove the bottom of the case, then plug and play. He also warranties his products for 5 years - on the longer end for electronics mfgs.
Sonics, aesthetics, form factor, expected longevity, etc. all play a role for me in why I chose the Tempo. Everything you read out there and my comments are all subjective and the differences between these amps are small - someone could very easily prefer any of them based on sonics alone. As an example, I don’t think the boXem Purifi amp is cold and sterile, but many others say that Purifi amps are sterile. My criticism of it is that I perceive it to have less body than the Tempo. The Purifi may actually be the most correct at amplifying the signal, which would theoretically make it the best at doing its job. I wasn’t at the recording session and don’t know, but what I do know is I kept searching for an amp after spending a fair amount of time with it.
Note: edited to clarify my decision to look beyond the Purifi amp was after extended listening to the Purifi
AGD’s GaNFET amps do have at least one differentiator vs other GaNFET designs - Alberto (AGD’s principal) uses GaNFETs that were specifically designed for audio applications and for which he was (I believe) the team leader for the group developing them. Due to some corporate actions, he ended up buying the entire stock of these devices and uses them in his amps, so no other mfg has these particular parts.
There’s more to choosing the AGD Tempo than just sonics. Alberto designs all of his amps so they are easily upgraded by the user. I recognize this also provides him an ongoing income stream, but it also allows me to simply plug in a new output stage as he makes improvements to this part of the circuit. In his other (more expensive) designs, this takes on the look of a vacuum tube - simply plug and play. For the Tempo, you remove the bottom of the case, then plug and play. He also warranties his products for 5 years - on the longer end for electronics mfgs.
Sonics, aesthetics, form factor, expected longevity, etc. all play a role for me in why I chose the Tempo. Everything you read out there and my comments are all subjective and the differences between these amps are small - someone could very easily prefer any of them based on sonics alone. As an example, I don’t think the boXem Purifi amp is cold and sterile, but many others say that Purifi amps are sterile. My criticism of it is that I perceive it to have less body than the Tempo. The Purifi may actually be the most correct at amplifying the signal, which would theoretically make it the best at doing its job. I wasn’t at the recording session and don’t know, but what I do know is I kept searching for an amp after spending a fair amount of time with it.
Note: edited to clarify my decision to look beyond the Purifi amp was after extended listening to the Purifi
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I sympathize with Tom's policies because I know that if you sell people a PCB and parts, the odds are about 90% that you will get it back as a pile of burnt parts and a demand they get their money back. Damn few people have what it takes to build an amp from scratch. That's the reason Class-A amps and chip amps are so popular, ie the odds of success are far greater, or should I say the odds of letting out the magic smoke are reduced.
IMHO, the AGD is an ugly toad that reeks of elitism. If you spend more than $100 on it, well LOL!
IMHO, the AGD is an ugly toad that reeks of elitism. If you spend more than $100 on it, well LOL!
We’re all welcome to our opinions on aesthetics and value, and can spend our money any way we choose.
What I find funny is there’s always a cadre of people in forums that believe spending more than $X amount of money (usually $100 or so) on something is elitism. Happens every time.
What I find funny is there’s always a cadre of people in forums that believe spending more than $X amount of money (usually $100 or so) on something is elitism. Happens every time.
Link to the three amps I’ve been referencing:
Neurochrome Modulus-286 (note: mine also has Guardian speaker protection)
boXem Audio Arthur 4215 Purifi-based amp
AGD Tempo di Gan
Neurochrome Modulus-286 (note: mine also has Guardian speaker protection)
boXem Audio Arthur 4215 Purifi-based amp
AGD Tempo di Gan
Just so you know, I am trying to keep the case I purchased from Modushop along with the all of the connections I installed on the case. Just trying to decide between the Modulus/Purifi/Nilai.. The only issue I would have with the Modulus would be the heat sink. I am really kind of gambling here as I have never compared these amps to hear what I may want. All I really have to go on is what many others have said about the Purifi amps being much better than the broken down icepower 1200as2 I have. I may just hold off a little while and start by building a DAC hat from iancanada first. Perhaps by that time I may look further into a SS build.
By the way, I emailed icepower about getting a schematic for my module because of failure, and here is what they wrote me back:
Unfortunately we can’t share schematics with our customers, since they are highly confidential. Also we may not share information which can help/lead to repairing of our modules (so damaged modules are scrapped and not repaired).
Sorry for the bad news.
By the way, I emailed icepower about getting a schematic for my module because of failure, and here is what they wrote me back:
Unfortunately we can’t share schematics with our customers, since they are highly confidential. Also we may not share information which can help/lead to repairing of our modules (so damaged modules are scrapped and not repaired).
Sorry for the bad news.
Regarding comparisons of middle-of-the-road, pedestrian amplifiers... It seems in blind testing, people can't tell the sound of one from the other,
https://www.avsforum.com/threads/ka...-and-movie-night-events.1496367/post-60198218
I bought a cheap ($200 new, on sale) Behringer A800 class D stereo amp. It measures pretty well, and delivers a lot of power (something like 200W per channel into 4 ohms). I was comparing it to a vintage ca. 1995 Hafler P1000 class AB amp. I thought I heard differences. Hafler = warmer, maybe a bit muddier mids, A800 = clearer, sharper, verging on harsh highs. Could I tell them apart in a double-blind test? I don't know.
The linked article is worth a look, I think.
https://www.avsforum.com/threads/ka...-and-movie-night-events.1496367/post-60198218
I bought a cheap ($200 new, on sale) Behringer A800 class D stereo amp. It measures pretty well, and delivers a lot of power (something like 200W per channel into 4 ohms). I was comparing it to a vintage ca. 1995 Hafler P1000 class AB amp. I thought I heard differences. Hafler = warmer, maybe a bit muddier mids, A800 = clearer, sharper, verging on harsh highs. Could I tell them apart in a double-blind test? I don't know.
The linked article is worth a look, I think.
That has actually not been my experience. I've had very few mishaps with the Modulus-86 builds. Of those mishaps, all but one or two could be solved via email. Mistakes happen... I haven't kept accurate records, but it's my general sense that fewer than 1% of MOD86 builders require help with the build.
Compare that with around 20% of Modulus-286 Rev. 1.1 - the last board I offered with significant DIY SMD assembly. Some of those MOD286 mishaps were pretty hard to debug. Including one build where a ceramic capacitor had cracked during the assembly and resulted in high distortion in one channel. Another builder swapped C38 for R38 (or something similar). Well. It just so happened that the capacitor was a decoupling capacitor and the resistor a 0 Ω one, so the power supply got shorted out. That was easy to spot but only because I'd happen to choose a 0 Ω resistor that was green. So as soon as I saw the pictures I knew what the issue was as there shouldn't be a green part where a (grey) capacitor should be. Now you know why I don't offer DIY SMD builds... 🙂
People are humans. Mistakes happen.
Tom
That is strange... I can tell the difference between amplifiers very easily in a blind test. Of course, after 30min or so I get tired and it becomes harder to tell the difference. But, if I put an amp in my system and then listen to it for a couple of days, and then swap... the difference is very obvious; night and day. Doing a fast A/B blind test, especially for a prolonged duration, does tend to confuse people.
The best is to give yourself a few days and listen while doing something else... the good choice would be doing something that requires a bit of brain involvement, like writing an essay or a (PLC) code. Then it is quite easy to get irritated with a bad-sounding amp.
I mentioned already that class D amps of the modern age sound like a wire with gain; they brutally reveal the quality of the source. With a very good source, they can sound amazing sans the 3D holographic portrayal I get only with a 2-gain stage, class A single-ended designs. What is interesting is the fact that Japanese class AB amps sound pretty bad to everyone in my family (kids play instruments... have very astute hearing. To them, the only amp worth listening to is that 2-gain stage single-ended class A amp I mentioned earlier... to add, they also like records much better than digital audio).
"Unfortunately we can’t share schematics with our customers, since they are highly confidential. Also we may not share information which can help/lead to repairing of our modules (so damaged modules are scrapped and not repaired)."
If this is indeed true, I'm voting with my feet. No to Icepower.
I've already had three Hypex UCD400MP (UcD400 + integrated power supply) fail.
1- a fellow forum member blew the amp on his B&W PV1D subwoofer, and asked around if anyone had a spare, which I happen to have laying (for a multichannel amplifier project that I never got off the ground). If you search the www for "PV1D amplifier" there seems to be a few hits hmm...
2- a bug (not the software bug, the old fashioned kind) - It seems creepy crawlies like finding warm places to live, like amplifiers in the Outback. A thumbnail so you don't vomit.
3. TBD - user (my) error I hope. If this fault related to something else intrinsic to the board.
Furthermore, my 11 yo Hypex nCore400 is now NLA.
So no repair or replacement.
Or there even a drop-in replacement with the same mounting holes and interconnects? Of course not.
Sustainability... let's just kick the can down the road...
I reached out to @tomchr for a fully built 6 multichannel solution, or at least twin 3 channel solution.
Something that's repairable and won't go to scrap heap.
Watch this space.
If this is indeed true, I'm voting with my feet. No to Icepower.
I've already had three Hypex UCD400MP (UcD400 + integrated power supply) fail.
1- a fellow forum member blew the amp on his B&W PV1D subwoofer, and asked around if anyone had a spare, which I happen to have laying (for a multichannel amplifier project that I never got off the ground). If you search the www for "PV1D amplifier" there seems to be a few hits hmm...
2- a bug (not the software bug, the old fashioned kind) - It seems creepy crawlies like finding warm places to live, like amplifiers in the Outback. A thumbnail so you don't vomit.
3. TBD - user (my) error I hope. If this fault related to something else intrinsic to the board.
Furthermore, my 11 yo Hypex nCore400 is now NLA.
So no repair or replacement.
Or there even a drop-in replacement with the same mounting holes and interconnects? Of course not.
Sustainability... let's just kick the can down the road...
I reached out to @tomchr for a fully built 6 multichannel solution, or at least twin 3 channel solution.
Something that's repairable and won't go to scrap heap.
Watch this space.