"Pure Class A"

[Mr Peabody]

mlsstl is talking about LP's, is that what you refer to also , E-stat?

Frenchmon, Clayton is local. I didn't realize or forgot about Herron, I'd really like to hear some of that. MFP has some of the Clayton around. I'm not sure if any one displays the Herron but I think I will see if I can email them.

Sometimes plots and curves look good on paper but don't seem to match real world use. My MV60 is rated at 50 wpc and it was good with my Dyn's to a comfortable listening level and could have been fine for some but I felt my system needed more power. With them being mono the power is sufficient unless reaching real loud levels. I should get my meter out sometime and see what SPL some of my listening is. I know I have a Reference CD of Classical, Music for Pipes & Brass, it takes a Krell to get that to slam like it's supposed to. I have had the amps reach their limit before but I never listen at that level. I never got my 500i to it's limits. Nor, did I the 300i as far as that goes.

[E-Stat]

Here's an image from the finale of Wagner's "Ride of the Valkyries"

Which is significantly less "spikey" than my example. Yours looks more like pop music. It is those infrequent spikes that require more juice.

Note the orchestra is cranking along with a lot of fervor at full tilt. You can see the volume bar at the bottom of the screen shot shows right at - 6 dB. That means there is 6 dB of headroom left for peaks.

You'll notice with mine that the right channel has already clipped.

This is pretty typical of classical recordings.

My example is an atypical recording. One of those exceptions to which I refer.

My primary point all along has been is that if you are getting the volume you want on the average loud portions of a record from just a couple of watts, there is nothing on a recording that is going to produce a sudden demand for 200 or 300 watts.

There is a reason why Sound Lab burns in their speakers at the 800 watt level. I've met the designer and visited their facility in Utah.

rw

[E-Stat]

mlsstl is talking about LP's, is that what you refer to also , E-stat?

I'm talking about any source for my main system to reach peaks of about 90 db. It takes 600 watts. The stats are not efficient and require more grunt.

rw

[mlsstl]

Which is significantly less "spikey" than my example. Yours looks more like pop music. It is those infrequent spikes that require more juice.

"Pop music"? Hmmm, just can't have a conversation without a few digs? Interesting.

The frequency or infrequency of a spike is irrelevant to the subject. Zero dB is zero dB on a recording, regardless of where it came from or how often it happens.

You'll notice with mine that the right channel has already clipped.

Not sure what you mean by this. I see nothing attached to examine. Could you clarify?

Plus, if a peak is clipped on the recording itself, no amount of power in the world from the amp will unclip it.

[Ajani]

As we can see from the posts in this thread so far:

Amplifier Power requirements vary from user to user... Persons like RGA, prefer above average to High Efficiency Speakers with low powered Class A and/or Tube Amps... Others prefer Low Efficiency Speakers that like to be dominated by a big brute (I didn't make up that line - I read it in a review once)... Personally, I like 50 Watt Amps driving anything from Just below Average to Fairly Efficient Speakers (in a small to medium room)...

I've ruled out Class A amps, simply because of the the heat and cost to get a 50 Watt Class A... And besides, I am feeling the strong urge to embrace the love whose Naim I dare not speak, as a Christmas present to myself...

[audio amateur]

I've ruled out Class A amps, simply because of the the heat and cost to get a 50 Watt Class A... And besides, I am feeling the strong urge to embrace the love whose Naim I dare not speak, as a Christmas present to myself...

Ummm, what are you going to drive with a Naim?

[Ajani]

Ummm, what are you going to drive with a Naim?

Naim? Who said anything about Naim???

Hypothetically, If I was to get a Naim, I'd be pairing it with Revel....

[E-Stat]

"Pop music"? Hmmm, just can't have a conversation without a few digs? Interesting.

It's not a dig. Your example is not particularly dynamic.

The frequency or infrequency of a spike is irrelevant to the subject. Zero dB is zero dB on a recording, regardless of where it came from or how often it happens.

My point is the spike is just that - a major dynamic contrast. Here's another example of a fun piece from Harry Potter and the order of the Phoenix. This is the "Hall of Prophecy" cut - a very emotional piece with "raise the hair on your arms" dynamic impact. Click here to view. Another is from John William's score of Memoirs of a Geisha. Here is the "Rooftops of Hanamachi" where Sayuri is trying to find her sister. It is another emotional piece with impact. Click here for that example. One last falls into the "f--ing awesome" category. Here is a cut of Chinese drum music. The first time I heard this it was played on Nola Grand References with Krell amps on the woofer towers and VTL Wotans on the mains. The opening bars will STARTLE the crap out of you with its dynamic impact. Look here for this example. Etc., etc..

Not sure what you mean by this. I see nothing attached to examine. Could you clarify?

Since the image was large, I made it a link instead. Click the blue link that says "Dynamics"

Plus, if a peak is clipped on the recording itself, no amount of power in the world from the amp will unclip it.

No debate there.

rw

[Mr Peabody]

Come on Ajani, what are you thinking about getting, how bad could it be? Are you springing for that Sherwood/Bose system you've dreamed about?

[Ajani]

Sherwood/Bose system

[frenchmon]

mlsstl is talking about LP's, is that what you refer to also , E-stat?

Frenchmon, Clayton is local. I didn't realize or forgot about Herron, I'd really like to hear some of that. MFP has some of the Clayton around. I'm not sure if any one displays the Herron but I think I will see if I can email them.

Sometimes plots and curves look good on paper but don't seem to match real world use. My MV60 is rated at 50 wpc and it was good with my Dyn's to a comfortable listening level and could have been fine for some but I felt my system needed more power. With them being mono the power is sufficient unless reaching real loud levels. I should get my meter out sometime and see what SPL some of my listening is. I know I have a Reference CD of Classical, Music for Pipes & Brass, it takes a Krell to get that to slam like it's supposed to. I have had the amps reach their limit before but I never listen at that level. I never got my 500i to it's limits. Nor, did I the 300i as far as that goes.

If you do get a chance to listen to the Herron amps let me know....I thik they are all tubs.

I think your amps where 50 watts perchannel and you had them modded so they are 100 mono correct?

frenchmon

[LeRoy]

So what is "pure class A". Just about every "pure class A" amp is low in wattage and very expensive. How does a "pure class A" amp at 35 watts per channel compare to a non-pure class a amp at 200 watts per channel?

frenchmon

Well it seem like I am late to this thread as well...

With regard to your original inquiry, I think Belles and Pass Labs make the benchmark class A amplifiers with Belles being more affordable. Yes, the class A amps do get quite warm and do need space around them to keep them ventilated. With regard to quality of sound, I simply love the SA30 & VT01 over anything I have heard to date including my Soloist (purchased as a demo units for $1100). I have yet to hear any distortion from my Soloist and have yet to hear any distortion through the SA30 VT01 combination regardless of volume setting.

I have my XRAY paired up with the Soloist 3 & 5 and it's a very good musical match. The XRAY also is a great match with the SA30 & VT01 but the XRAY is not quite in the same
league as the Lector CDP-7T/Mk III (now selling for roughly K$5.5).

For reviews of Belles equipment..

Statement Series, check out these particular reviews
SA 30 amp
VT-01 pre-amp

For the Soloist, check out the reviews
Soloist 3 Preamp
Soloist 5 Amp

The reviewed units, SA30 and VT01 (the units reviewed on Soundstage), are the very units I have had the pleasure of listening to at my local audio dealer's home. I did hook up the XRAY into this amplification and the speakers were the Reference 3A Episode.

Depending on how long you are willing to wait, my local audio dealer advised that Belles in coming out with a new integrated amp that basically is a combined and upgraded Soloist.

http://www.powermodules.com/power_modules/Home.html

Good luck with the research and have fun shopping.

LeRoy

[blackraven]

Belle's makes nice stuff. A good friend of mine owns a Belle's Hot Rod amp and it sounds great.

[RGA]

As we can see from the posts in this thread so far:

Amplifier Power requirements vary from user to user... Persons like RGA, prefer above average to High Efficiency Speakers with low powered Class A and/or Tube Amps... Others prefer Low Efficiency Speakers that like to be dominated by a big brute (I didn't make up that line - I read it in a review once)... Personally, I like 50 Watt Amps driving anything from Just below Average to Fairly Efficient Speakers (in a small to medium room)...

I've ruled out Class A amps, simply because of the the heat and cost to get a 50 Watt Class A... And besides, I am feeling the strong urge to embrace the love whose Naim I dare not speak, as a Christmas present to myself...

An Acoustat owner - Mr. Acoustat - has difficult to drive Stats - he recently bought a Grant Fidelity Rita integrated 45 watts pure class A power amp (it does have peak ability to 450watts). And best of all the amp runs cooler than your average Receiver due to a unique design. And I mean it - it runs cool!

So it is cool running tube amp, and can drive pretty much anything with no problem - I have seen nothing built better for $4k - except maybe the Shengya PM 150 monoblocks I have on hand. $1200 each built like a tank - cool running tube hybrid A/B monoblock amplifiers and 300 watts into 4ohms.

The downside of the Rita is that it is so ridiculously heavy 145lbs that you can put your back out moving it around. http://www.soundstageav.com/onhifi/20081001.htm Their price of $5299 has been reduced to $4200US

[Mr Peabody]

A guy had a pair of Acustats on CL for $250.00. By the time i contacted him they were gone. I really didn't have the room for them. He was one of those guys who was into audio for a while and eventually the system ended up in the garage and he just wanted to get rid of it. Some one got an unreal deal.

Do those Shengya sound good? That's some cheap tube watts.

[mlsstl]

E-Stat, sorry for the delayed response, but it was a hectic weekend.

I took a close look at your music piece. While it looks impressive, the average level in the loud section is about 8 to 9 dB down from zero. That isn't all that terribly different from what I posted earlier.

The scale range one uses for graphic display has a lot to do with appearances. From zero dB on your graph to -6 dB is half way to the infinity mark. The scale markings on your graph are such that they tend to magnify things to make for more dramatic looking peaks.

Your soft material before the loud part is about 18 dB down.

The front end of the piece I clipped from my music selection also is around 18 dB down, so even though yours has a longer selection of soft volume material, and even though yours "looks" more dramatic, there isn't all that much difference in dynamic range.

Your peaks are about 3 dB higher than the peaks in the piece I used.

You've also stated previously that you have vary inefficient speakers and need 50 watts just for an average volume.

Several messages ago I clearly stated that if one needs 50 watts for average power, then having hundreds available for peaks is very reasonable. If just one or two watts is giving your average volume, then those enormous power reserves make less sense.

As such, I'm not quite sure where the point of disagreement lies.

[E-Stat]

E-Stat, sorry for the delayed response, but it was a hectic weekend.

Apology unnecessary.

I took a close look at your music piece. While it looks impressive, the average level in the loud section is about 8 to 9 dB down from zero. That isn't all that terribly different from what I posted earlier.

Perhaps, but it is not the average levels to which I refer. If the piece you're talking about is the first one (Rite), you're cruising along at -20 db for nearly two minutes then WHAM - full gain! Wait two seconds, then again! The "Rooftops" piece shows even more contrast between average and peak levels.

The scale range one uses for graphic display has a lot to do with appearances. From zero dB on your graph to -6 dB is half way to the infinity mark. The scale markings on your graph are such that they tend to magnify things to make for more dramatic looking peaks.

Far more dramatic scaling? 50% vs. 40%? It sure doesn't look like the Adobe application is much different from Sony's.

The front end of the piece I clipped from my music selection also is around 18 dB down, so even though yours has a longer selection of soft volume material, and even though yours "looks" more dramatic, there isn't all that much difference in dynamic range.

Yet the average levels are quite different when you consider all the examples I've provided. Therein lies the difference.

As such, I'm not quite sure where the point of disagreement lies.

Probably not. On the other hand, I certainly don't power my system "in preparation for the fraction of a second that may or may not ever occur". It is those fractions of a second that I most certainly use every last milliwatt of power I have to achieve peaks of barely over 90 db measured at listening distance.

rw

[RGA]

A guy had a pair of Acustats on CL for $250.00. By the time i contacted him they were gone. I really didn't have the room for them. He was one of those guys who was into audio for a while and eventually the system ended up in the garage and he just wanted to get rid of it. Some one got an unreal deal.

Do those Shengya sound good? That's some cheap tube watts.

I am currently away from home and can't do a lot of evaluations - I was reviewing something else so I have not given much audition to the Shengya monoblocks. I am also waiting for a proper CD player to come in to give both the Rotel and Shengya's a proper evaluation. I am hoping to get an Audio Note CD player soon to get a better foundation for my digital front end.

But I can say I like what I have heard so far - of course that power is lost on my speakers. But the point was to have something like this to be able to review tough to drive speakers. Obviously the OTO limits my options.

I do have a few exceptions in the hard to drive speakers camp that I like - Soundlabs coincidentally.

[mlsstl]

Perhaps, but it is not the average levels to which I refer. If the piece you're talking about is the first one (Rite), you're cruising along at -20 db for nearly two minutes then WHAM - full gain! Wait two seconds, then again! The "Rooftops" piece shows even more contrast between average and peak levels.

If you are playing the soft section of the Rite of Spring at a loud 90 dB, then you intrinsically listen to music differently than I. I think the quiet sections of compositions should be played quietly.

If I'm running the quiet section at 70 dB in my room, my particular system is not going to need a zillion watts to hit the 20 dB louder "WHAM" peak at 90 dB.

And it really doesn't matter if this 20 dB happens every two seconds, every 30 seconds or only once. The recording itself has a maximum limit and there is nothing hidden beyond that. If the amp is decent quality and adequate to deliver the needed power once, it can also deliver it every two seconds.

My comment about the scaling was that while your version "looks" far more dramatic in terms of dynamics, it really isn't that much more when you run the actual numbers. Your loud section has 8 or 9 dB peaks above average. That's pretty good for a lot of recordings, but hardly unheard of. You keep claiming an unusually large dynamic range for this piece that I simply don't see when I look at it.

I guess this qualifies as a fundamental difference in perspective on the issue. The conversation has turned repetitive so there's not a lot of point in our continuing. Anyone who is interested can read through and come to their own conclusion.

The last word is yours and don't forget to enjoy your music!

[Ajani]

If you are playing the soft section of the Rite of Spring at a loud 90 dB, then you intrinsically listen to music differently than I.

Actually, I think E-Stat was saying that his speakers are so inefficient that it takes a load of power for him to hit the peaks at 90DB... So the soft sections might even be lower than what you listen at...

[mlsstl]

Ajani wrote: "Actually, I think E-Stat was saying that his speakers are so inefficient that it takes a load of power for him to hit the peaks at 90DB"

Actually, if you read back a bit, there isn't disagreement about that issue.

[E-Stat]

... don't forget to enjoy your music!

That I do on a daily basis!

rw

[Carlos Ved]

Hi. I am from Portugal. My 17 year old amp no longer works. Apparently it is the On-Off switch which is broken. Locally the distributor is unable to source the right component which looks lika a small rod with a base and 4 pins underneath. Can anybody help ?

[audio amateur]

Hi. I am from Portugal. My 17 year old amp no longer works. Apparently it is the On-Off switch which is broken. Locally the distributor is unable to source the right component which looks lika a small rod with a base and 4 pins underneath. Can anybody help ?

Perhaps you can contact Musical Fidelity in the UK and ask to have the piece sent? Or try another MF dealer in Portugal?

[jrhymeammo]

Wow,

See this is what happens when I'm working 70 hours a week. Missing out on some great threads here at AR. Coincidentally I had purchased a pair of Aleph5 made by Tim Rawson.
Pure Class A at 70/8 ohm, 100/4 ohm with 100,000 uf.

Time to crank my AC in January!!

JRA