amp pricing

[moves]

There are a set of amps that are very near to each other in price range. I am talking about Macintosh, Bryston, and Classe. What makes one buy one over the other... The Bryston has a 20 year warranty which is hard to ignore. The Classe is just beautiful but.. expensive. A little more then the other 2 but I could be wrong. What do you think is the difference between these rigs?

 

[templemaners]

There are a set of amps that are very near to each other in price range. I am talking about Macintosh, Bryston, and Classe. What makes one buy one over the other... The Bryston has a 20 year warranty which is hard to ignore. The Classe is just beautiful but.. expensive. A little more then the other 2 but I could be wrong. What do you think is the difference between these rigs?

Honestly, I think it's just aesthetics. I'm sure all 3 brands are high quality in terms of the parts used and the internal design (they should be for as pricey as they are), so I think it's just a matter of what you think looks best.

 

[Irvrobinson]

There are a set of amps that are very near to each other in price range. I am talking about Macintosh, Bryston, and Classe. What makes one buy one over the other... The Bryston has a 20 year warranty which is hard to ignore. The Classe is just beautiful but.. expensive. A little more then the other 2 but I could be wrong. What do you think is the difference between these rigs?

McIntosh uses output transformers in their amplifiers, which is a design feature I simply don't like. It raises cost without benefit, and I'd rather they spend more on a great power supply and output stage that can provide constant voltage even as impedance drops. I've never understood the constant current argument. Other than that, I think that of the three brands the McIntosh has the best overall quality, and I have to admit I'm sucker for their properly designed (and expensively designed) power output meters. Nonetheless, for super high-end amps I like Krell much better, based on years of measurement. Gene has also spoken very highly of the Pass Labs amps, but they're also very pricey (and a lot of money is spent on machined aluminum).

The Brystons do have a nice warranty, and they are certainly good performers, but I think they've gotten rather pricey over the years for the parts they use.

Classe has been acquired by B&W, and the CA 2300 seems like a great product, but I have to agree that you're paying a lot for aesthetics.

The last time I went shopping for a more power amplifier to replace my Levinsons I settled on the ATI AT3000. The aesthetics aren't very good, think 1980s Adcom, but the combination of performance and price is very good, if you want to stick to Class AB.

 

[moves]

what's an output transformer?

 

[fuzz092888]

Unless I'm mistaken, and Irv will correct me if I'm wrong, but it's something that keeps the current constant, IE most amps will have greater WPC as the impedance/resistance drops, while Mc gear will output XXX amount of WPC no matter what the resistance.

Whereas in a properly designed (well designed) amp without an output transformer, the WPC will double down, but at the very least increase as the impedance/resistance drops.

 

[Irvrobinson]

what's an output transformer?

It is a device for matching the load of the speakers to the final driver stage of the amplifier, well, at least providing an approximate match. On the back of a McIntosh amp you'll notice three sets of speaker terminals, one each for 2, 4, and 8 ohms. Each set of speaker terminals uses a different winding on the transformer, in an attempt to make the amplifier a constant current device. This means you theoretically get a minimum, for example, of 300W into any speaker impedance, rather than have the power output vary with the rated impedance of the speakers.

Output transformers were originally used in tube amplifiers because it gets very expensive and power-inefficient to build tube circuits that can handle low impedance speakers. McIntosh, uniquely in my memory, decided to use output transformers even with solid state amplifiers. Since bipolar transistors don't need the crutch of a transformer for output matching, they can scale current as impedance decreases to keep output voltage more constant, McIntosh's design choice has always mystified me, especially considering how much the impedance load of modern multi-driver electrodynamic speakers varies over their frequency range. A 4-ohm speaker is seldom ever really a 4-ohm load. Anyway, even the most coveted tube amps have tried to eliminate output transformers (they're called OTL amps), so I've always thought of output transformers as a crutch, not a desired feature. Transformers are also expensive devices once you need a high power rating, since you need to go big and be precise to avoid saturation.

Anyway, output transformers, or Autoformers as McIntosh calls them, is IMHO a design wart on otherwise awesome products.

 

[mtrycrafts]

... The aesthetics aren't very good, ....

Easily rectified. Place a nice panoramic picture in front of it.

 

[flyboylr45]

Hey guys sorry for the poor copy-paste, but here is an explanation of Autoformers and why they use it directly from the manual of my MA-7000.


Autoformers
All solid state power amplifier output circuits work best into what is called an optimum load. This optimum load may vary considerably from what a loudspeaker requires. In the case of more than one loudspeaker connected in parallel, the load to the power amplifier may drop to two ohms or even less. A power amplifier connected to a load that is lower than optimum, causes more output current to flow, which results in extra heat being generated in
the power output stage. This increase in temperature will result in a reduced life expectancy for the amplifier.
The Autoformer creates an ideal match between the power amplifier output stage and the loudspeaker. Refer to figure 13. There is absolutely
no performance limitation
with an Autoformer. Its fre-
quency response exceeds that
of the output circuit itself,
and extends well beyond the
audible range. Its distortion
level is so low it is virtually
impossible to measure. In the
rare event of a power ampli-
fier output circuit failure,
the McIntosh Autoformer
provides absolute protection
from possible damage to your valuable loudspeakers.

Protection Circuits
The MA7000 incorporates its version of the McIntosh Sentry Monitor output transis-tor protection circuit. Refer to
figure 14. There is absolutely no compromise in sonic performance with this circuit, and it ensures safe operation of the
amplifier under even the most
extreme operating conditions.
The different types of protec-
tion circuits incorporated in the MA7000 insure a long and safe operating life.
The MA7000 also includes the unique patented McIn- tosh Power Guard circuit. Power Guard eliminates the pos- sibility of ever overdriving the ampli-
fier into clipping. Refer to figures 15,
16 and 17. An overdriven amplifier
can produce both audible and inaudi-
ble distortion levels exceeding 40%.
The audible distortion is unpleasant
to hear, but the inaudible ultrasonic
distortion is also undesirable, since
it can damage valuable loudspeaker system tweeters. You will never experience the harsh and damaging distortion due to clipping.
Technical Description, con’t
The Power Guard circuit is a
waveform comparator, monitoring
both the input and output wave-
forms. Under normal operating con-
ditions, there are no differences be-
tween the shape of these waveforms.
If an amplifier channel is overdriven,
there will be a difference between
the two signal waveforms. When the
difference exceeds 0.3%, the Power
Guard activates the PG light and a
dynamic electronic attenuator at the
amplifier input reduces the input
volume just enough to prevent any
further increase in distortion. The
Power Guard circuit acts so fast that there are absolutely
no audible side effects and the sonic purity of the music reproduction is perfectly preserved. The MA7000 Ampli- fier with Power Guard is not limited to just the rated power output, but will actually produce distortion free output well above its rated power due to the McIntosh philosophy of conservative design.
Power Supply Circuits
To compliment the design of the MA7000, there is a high voltage power supply for both channels. The power amplifiers draw high current from the AC power line. Therefore, it is important that they plug directly into the wall outlet. Turn on inrush current is cushioned by therm- istors in the power transformer’s primary circuit. This soft start eliminates component stress during turn-on.
The MA7000 can provide greater than 50 amperes peak output current to drive uneven speaker loads. Some poor speaker designs have input impedance that dip to 1 or 2 ohms at various frequencies and the MA7000 has the out- put current reserve to drive them. The MA7000 has main filter capacitors that guarantee an excellent signal to noise ratio and the energy storage necessary for a wide dynamic range that music demands.
Figure 16
Figure 17
Figure 13
Normal Operating Area
Sentry Monitor Safety Area
Output Transistor Failure
Figure 14

 

[Irvrobinson]

All solid state power amplifier output circuits work best into what is called an optimum load. This optimum load may vary considerably from what a loudspeaker requires. In the case of more than one loudspeaker connected in parallel, the load to the power amplifier may drop to two ohms or even less. A power amplifier connected to a load that is lower than optimum, causes more output current to flow, which results in extra heat being generated in
the power output stage. This increase in temperature will result in a reduced life expectancy for the amplifier.
The Autoformer creates an ideal match between the power amplifier output stage and the loudspeaker.

IMHO, this is really engineering baloney. The output transformer effectively acts as a current limiter to the speaker, by increasing the impedance as seen by the amplifier's output stage, which reduces the delivered current to the speaker. All of that stuff about low impedance reducing amplifier life is just so much more baloney, as that's only true if the amp is improperly cooled.

Most 300W/ch/8ohm solid state amps these days will put out at least 150% of their 8 ohm power into 4 ohm loads, and most amps in the McIntosh's 300Wx2 price range will put 200% into a 4 ohm load. I don't know what McIntosh spends on those autoformers, but I'd rather have them beef up the power supply and the output stage to act as a linear voltage source, because that's what drives most speakers best these days.

Now before you get all up in arms, flyboy, rest assured you've got one heck of a nice amp there, and the fact that I think McIntosh is carrying on a dumb design tradition from decades ago, just like GM with those transverse springs in a Corvette, is probably 99% irrelevant. I doubt you'll need more than rated power into those Focals. (In their defense, GM did switch to plastic for the springs, which makes them the most lightweight and sophisticated mechanical springs on any production car, but the transverse thing is just a silly throwback to the 60s too.) I'm just a product development purist, and the fact that they're, in my opinion, designing for outdated marketing messages, just annoys me. I'd just ignore me.

 

[flyboylr45]

lol lol, trust me, I don't take anything personal. Just posted it for informational purposes from the manufacturer. I really love the way the combination of the amp and focals sound.

 

[Irvrobinson]

I really love the way the combination of the amp and focals sound.

And that is what this hobby is all about. Actually, my local Velodyne dealer is also a McIntosh dealer, and when I bought the Velodyne sub I admit to coveting the McIntosh's power meters in the amp he used for the demo. (And, for ADTG, the main speakers in the demo were B&W 802D2s. )

 

[flyboylr45]

Ah yes, the meters. They are awesome during the day. You almost have to force yourself to not stare at them. But at night, in a dark room it's a totally different story. They are really bright. One cool thing about the meters is seeing how many watts you're actually using. I have seen those meters hit 250 a few times!!!! I have yet to see the power guard lights come on.

And yes, I love this hobby cause there are as many opinions as there are components. It's all part of the fun. The amp, cd player and speakers are all connected with Blue Jeans Cables @ a very small fraction of the cost of the turntable, let alone the rest of the gear.

By far the biggest improvement in my system where the custom made cable lifters

Just kidding.....

 

[AcuDefTechGuy]

And that is what this hobby is all about. Actually, my local Velodyne dealer is also a McIntosh dealer, and when I bought the Velodyne sub I admit to coveting the McIntosh's power meters in the amp he used for the demo. (And, for ADTG, the main speakers in the demo were B&W 802D2s. )

Yeah, my B&W dealer is also a McIntosh dealer (& Classe & Rotel).

There's an amp for everyone just like there's a speaker for everyone.

In the end, I think all these high quality amps will do the same thing - amplify the original sound faithfully without coloring it. What you will hear is the sound of the original recording through the speakers and not the sound of the amp.

So I agree with Irvrobinson that it's more about price, aesthetics, pride of ownership, warranty, pro reviews, and peer reviews.

I would go with Bryston because of the 20 yr kick-a$$ warranty, kick-a$$ front metal handles (like my AT3000s and AT2000s amps), high quality, and great reputation. But that's my personal taste.

If ATI offered the same 20 yr warranty, I would never even look at another amp. ATI offers a 7 yr warranty, which is more than everyone else, except Bryston. Of course, the Bryston is also 3 times more expensive.

But the Bryston is so much lighter in weight than ATI, and I prefer lighter weight.

Speaking of light weight, Bryston also has class D amps, but their warranty is only 5 years. So only their SS amps carry the 20yr warranty.

 

[Irvrobinson]

I have seen those meters hit 250 a few times!!!

Which supports my theory about what it really takes to produce reference levels in a home. We argued about that in another thread.

 

[flyboylr45]

I was really shocked. My room is relatively small and has 9 acoustic panels with 2 huge bass traps. I can now see how inefficient speakers would need amps like the MC 1.2kw to reach reference levels in medium to big sized rooms.

 

[Enki]

damn that sounds pretty trippy.

 

[KEW]

I have seen those meters hit 250 a few times!!!!

Does McIntosh give any indication how responsive those meters are? That would make a huge difference in what type of numbers you would see. A very fast acting meter would catch quicker transients which might be equivalent to Dynamic power. A slow meter would be closer to RMS or continuous power.

They used to even give a spec called Instant Peak Power, which, if memory serves, was over ten-fold the RMS rating. However, I wouldn't think any mechanical meter could be fast enough to measure IPP.

 

[flyboylr45]

From the manual:
"They indicate to an accuracy of at least 95% of the power output with only a single cycle of a 2,000Hz tone burst."

As far as the instant peak power, I couldn't find anything. It does say this in the spec sheet,
"Power Output, 250 watts is the minimum sine wave continuous average power output per channel, both channels operating."

 

[ratso]

i have been convinced for quite some time that any amp with decent numbers will sound as good at the same decibel as any other (ie "all amps sound the same"). so i have to admit that i was very surprised (shocked even) to hear gene saying that he could hear a very audible difference from his new pass labs amp??? love to hear some more about this if he notices this post (pretty sure it was gene, apologies if it was someone else). is this difference measurable? i would love to hear more about this because for a long long time the pass X250 was my "dream amp" and i had just gotten over it. now i am thinking again... hmm... maybe....

 

[AcuDefTechGuy]

i have been convinced for quite some time that any amp with decent numbers will sound as good at the same decibel as any other (ie "all amps sound the same"). so i have to admit that i was very surprised (shocked even) to hear gene saying that he could hear a very audible difference from his new pass labs amp??? love to hear some more about this if he notices this post (pretty sure it was gene, apologies if it was someone else). is this difference measurable? i would love to hear more about this because for a long long time the pass X250 was my "dream amp" and i had just gotten over it. now i am thinking again... hmm... maybe....

Believe your own ears, not someone else's ears.

The people who say "amps are amps" have experienced for themselves and they also believe in DBTs. They are people like Toole, Linkwitz, GedLee, Olive, Peter Aczel, David Rich, Dennis Murphy. They have heard Krell, Mark Levinson, Bryston, Parasound, Boulder, Lexicon, McIntosh, Theta, etc, for themselves.

And the people who believe all amps have a sound of their own say that amp measurements are not everything - just because the amps measure the same does not mean they sound the same.

Believe your own ears.

It would be interesting to see a survey of amp sounds. How many people believe "amps have different sounds" and how many believe "amps don't have different sounds"?