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High end Vintage SS amp vs the best Class D amps
- Thread starter Goodman
- Start date
- Thread Starter
- #3
ABH-2 is not a class D amplifier but a "classic bi -polar amp" as you say. Did you tell "bias" ?
Thanks for the correction and the link, still looking for an answer.ABH-2 is not a class D amplifier but a "classic bi -polar amp" as you say. Did you tell "bias" ?
restorer-john
Grand Contributor
Plenty of anecdotal and subjective comparisons are out there, but they are full of fluff and thin on objective differences. The Benchmark is underpowered for a stereo power amplifier. As a bridged mono amplifier, it is in the realms of reasonably adequate power for a SOTA product, but you need two, and the performance drops off in some key areas.
Accuphase gear is essentially product you will own for your lifetime. You'll never want anything else. Ever. It costs a fortune, but is built absolutely beautifully, is extremely conservatively designed and their specifictions are very modest. They always outperform their "guaranteed" specs, particularly in the rated power department.
If you are looking for objective comparisons, it gets tricky and a whole slew of arguments ensue. There are performance parameters where "classic" amplifers exceed Class Ds and there are some Class Ds that challenge any, and all traditional designs in other areas. The playing field is not level unfortunately.
At this point, Class D in the forms of the Hypex and Purifi offerings are close to, but not equalling, other excellent topologies. But what they do for the money is essentially impossible to beat. That makes for a compelling value proposition for many people. Trouble is, the implementations are a 'wild west' of quality and there are only a few companies doing justice to the amplifier modules themselves.
Absolute SOTA in amplification is say, a Halcro Eclipse. As far as I am aware, nothing comes close in all the parameters that actually define a high fidelity amplifier. But a pair costs US$70k... (AU $120k in Aus). Ouch. They are my lottery winnings amps.
@boXem | audio (above) has a range of Class Ds. I have not used or heard any of his products, but based on the attention to detail in design and assembly, I would expect them to be a very good option, albeit at a much lower and affordable price.
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- Thread Starter
- #5
Good answer, John. If you add the amp matching or coupling to specific speakers, the problem of choice becomes even more complex, I have actualy bought a dozen power amps this year, the results are surprising both good and bad.Plenty of anecdotal and subjective comparisons are out there, but they are full of fluff and thin on objective differences. The Benchmark is underpowered for a stereo power amplifier. As a bridged mono amplifier, it is in the realms of reasonably adequate power for a SOTA product, but you need two, and the performance drops off in some key areas.
Accuphase gear is essentially product you will own for your lifetime. You'll never want anything else. Ever. It costs a fortune, but is built absolutely beautifully, is extremely conservatively designed and their specifictions are very modest. They always outperform their "guaranteed" specs, particularly in the rated power department.
If you are looking for objective comparisons, it gets tricky and a whole slew of arguments ensue. There are performance parameters where "classic" amplifers exceed Class Ds and there are some Class Ds that challenge any, and all traditional designs in other areas. The playing field is not level unfortunately.
At this point, Class D in the forms of the Hypex and Purifi offerings are close to, but not equalling, other excellent topologies. But what they do for the money is essentially impossible to beat. That makes for a compelling value proposition for many people. Trouble is, the implementations are a 'wild west' of quality and there are only a few companies doing justice to the amplifier modules themselves.
Absolute SOTA in amplification is say, a Halcro Eclipse. As far as I am aware, nothing comes close in all the parameters that actually define a high fidelity amplifier. But a pair costs US$70k... (AU $120k in Aus). Ouch. They are my lottery winnings amps.
@boXem | audio (above) has a range of Class Ds. I have not used or heard any of his products, but based on the attention to detail in design and assembly, I would expect them to be a very good option, albeit at a much lower and affordable price.
restorer-john
Grand Contributor
I am biased towards classic, well built, and conservatively rated Class AB amplifiers from the era where specifications were exceeded and operational lifetime and user satisfaction were paramount.
Like you may have found, many amplifier and speaker combinations are hard or impossible to predict. Some just work and others don't.
We do however, have these load insensitive modern Class Ds that need to be given the opportunity to show their stuff. So far, I am not impressed, but I am amazed. Amazed at what you can get in such a small package, with so little wasted heat and such a small footprint.
For me and many others, efficiency in an amplifer is utterly unimportant. Just running your HVAC unit for 20 minutes or leaving a few lights on when you go to the shops is way more important and significant than an amplifier idling for a few hours. It's chickenfeed in the scheme of things.
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- Thread Starter
- #7
There is also the fact that anyone can be an audiophile manufacturer, just buy some hypex or Pascal or other modules and a nice thick aluminium box; take it to a show and you are in business. Other classes of amplification have been abandoned becose they require circuit design and reseach; class H is a good example.
restorer-john
Grand Contributor
@restorer-john
I'm going to take this opportunity to just say how much I appreciate your presence on this forum, the majority of people here would rather act cynical and bougie than take time to explain things to the less experienced.
I'm going to take this opportunity to just say how much I appreciate your presence on this forum, the majority of people here would rather act cynical and bougie than take time to explain things to the less experienced.
If your question is "classic" amplification vs "modern" class D, I have one anecdotal experience with one of my customers who measured FR and distortion from his speakers powered by my stereo Purifi on one side, good old class A monoblocs on the other side.
Amplifiers of equivalent power, level matched at 1 kHz, very well designed listening room.
Basically, the FR and distortion were almost the same above 150 Hz. But my amp was allowing 1.5 dB more on the whole spectrum below 150 Hz. So completely different sound balance at the end.
The beginning of your statement is true, even if a bit of attention is needed when integrating these modules and complying to various regulations requires a lot of work. The end is completely false. Getting a high performance class D requires a lot more engineering than a high performance class H. This is why only 3 to 4 companies are on the market supplying both minor and major OEMs.
Its because its hard to design a good class D implementation. Class A and A/B are pretty easy compared to class D.
restorer-john
Grand Contributor
Thank you.
restorer-john
Grand Contributor
I would say a Class D from scratch would be incredibly challenging. Beyond my abilities for sure. A class D from a bulletproof module- not hard at all. Hypex and Purifi are handing the crown jewels to the assemblers. All they have to do is not f#%k it up. Some do, some don't.
Super high performance Class AB is an art and it sadly appears much of the gurus have retired or died, and it's almost like it's being re-discovered/re-invented again. Look at the AHB-2 Benchmark. It uses 1980s technology, wrapped up in a few (?) patents and hand waving. But it works..
Does this imply that a “load tolerance” test which measures output fidelity vs load angle is missing? Is there a figure of merit that could arise from such a test?
https://www.stereophile.com/content/boulder-amplifiers-2150-monoblock-power-amplifier-measurements
I would say one of the best high power amplifiers ever built.
I would say one of the best high power amplifiers ever built.
Amplifier testing is not on the top here in ASR reviews.
I’m going to jump in with a completely passive but important reason for loving the new class-D amps. I was sceptical that class d could perform in real world conditions. Light and inexpensive seems to be counter intuitive. An amp that has 6 channels rated at 4ohm @500 WPC. That’s 3K on tap. In a unit that is the size of a Blu-ray player and maybe lighter in weight. I said “No-Way”. Then Amir did some measurements and a tear down review. All this power for under $1.6K? But in the end, in actual use case operation, all of the above faded away to background noise rationale.
You see I live in South Florida. The land of high heat and humidity. Where the home is locked up tight running A/C 9 to 10 months out of the year. Where the Electric bill runs second only to your Mortgage payment. It’s the Heat, or rather the lack of any! Pushing low Ohms load speakers this little 6ch Amp barely gets warm. My previous Amps were like room heaters pumping out gobs of heat. That I then had to run the A/C temp thermostat even lower to compensate. This major benefit was unexpected but most welcome. My cooling costs have dropped more than 30% this year alone. Essentially paying for the Amp in its first year of use. For comparison last year I averaged 10 run hours a day on the A/C. This year I am seeing 6 to 7 hours a day. The outside temperature has been essentially the same over the time period. 30% reduction in run time on my A/c System is another form of savings not calculated.
Use case FYI. I run my gear hard. My System is on for about 12-14 hours a day. Every day. I am retired and have some mobility restrictions. My use case is pretty extreme but I think it’s worth consideration. The cost savings are derived from the increased efficiency of the amps themselves and the reduced heat output as it relates to cooling needs of the home. I came to the class D amps for the improvements in the normal power amp specs. However, I will keep this amp and replace all the rest of my amps with class D for the Heat factor. Hard to beat purchases that pay for themselves.
You see I live in South Florida. The land of high heat and humidity. Where the home is locked up tight running A/C 9 to 10 months out of the year. Where the Electric bill runs second only to your Mortgage payment. It’s the Heat, or rather the lack of any! Pushing low Ohms load speakers this little 6ch Amp barely gets warm. My previous Amps were like room heaters pumping out gobs of heat. That I then had to run the A/C temp thermostat even lower to compensate. This major benefit was unexpected but most welcome. My cooling costs have dropped more than 30% this year alone. Essentially paying for the Amp in its first year of use. For comparison last year I averaged 10 run hours a day on the A/C. This year I am seeing 6 to 7 hours a day. The outside temperature has been essentially the same over the time period. 30% reduction in run time on my A/c System is another form of savings not calculated.
Use case FYI. I run my gear hard. My System is on for about 12-14 hours a day. Every day. I am retired and have some mobility restrictions. My use case is pretty extreme but I think it’s worth consideration. The cost savings are derived from the increased efficiency of the amps themselves and the reduced heat output as it relates to cooling needs of the home. I came to the class D amps for the improvements in the normal power amp specs. However, I will keep this amp and replace all the rest of my amps with class D for the Heat factor. Hard to beat purchases that pay for themselves.
restorer-john
Grand Contributor
MakeMineVinyl
Major Contributor
Class D from modules is harder class A/B from scratch? I guess I'll just call into work today and tell them to have the cleaning lady do the class A/B designs, and I'll go fishing.
Well, he said "Class D from scratch" not using a module. And the RF issues are an added complication.Class D from modules is harder class A/B from scratch? I guess I'll just call into work today and tell them to have the cleaning lady do the class A/B designs, and I'll go fishing.
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