Tube amps?

zumbo said:

The "pro gear" seems to cost less.

Ex: Crown, Ashley, Behringer.

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Right, and that's what I meant by "if cost is an issue". If cost is not an issue, you can obtain similar performance to the pro-gear, but at much higher prices, using hi-end gear. The only benefits that hi-end gear brings to the table so far as I can tell are: cosmetics, bragging rights and pride of ownership.

-Chris

zumbo said:

The "pro gear" seems to cost less.

Ex: Crown, Ashley, Behringer.

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Yes it does, why is that I wonder? I always thought pro amps would only sound good for sound reinforcement and guitars and such. That does not seem to be the case. Some pro amps look awesome for the money. Are they just priced fairly and home audio is not? I would not be surprised at all if that is the truth.

WmAx said:

Right, and that's what I meant by "if cost is an issue". If cost is not an issue, you can obtain similar performance to the pro-gear, but at much higher prices, using hi-end gear. The only benefits that hi-end gear brings to the table so far as I can tell are: cosmetics, bragging rights and pride of ownership.

-Chris

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http://www.proaudiosuperstore.com/Ashly-MFA8000.html

I do know that pro amps used to be different designs than most home audio amps. Class H and such instead of class A or B or A/B. Is that still true?

jeffsg4mac said:

I do know that pro amps used to be different designs than most home audio amps. Class H and such instead of class A or B or A/B. Is that still true?

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The Ashly stuff is class A.

jeffsg4mac said:

I do know that pro amps used to be different designs than most home audio amps. Class H and such instead of class A or B or A/B. Is that still true?

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Depends on the specific model. Most pro amps are switching amplifiers(Class D, H, T, etc.). But modern well-designed switching amplifiers perform perfectly. Some pro amps(such A500) are class AB, just like most hi-fi amplifiers.

-Chris

zumbo said:

The Ashly stuff is class A.

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Which Ashly stuff is class A? Class is the most inefficient class of operation. No way could Ashly compete in the business if they had to implement thermal dissapation and power supplies that are several times the capacity as required by other operation classes.

-Chris

WmAx said:

Depends on the specific model. Most pro amps are switching amplifiers(Class D, H, T, etc.). But modern well-designed switching amplifiers perform perfectly. Some pro amps(such A500) are class AB, just like most hi-fi amplifiers.

-Chris

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Hmmm, that A500 seems like the answer to my needs or wants anyway. The drivers I was considering are 4 ohms so in series they will be 8. The A500 will do 500 watts mono into 8 ohms. More than enough to drive dual 10's and only 179.95. American musical will let you spread those payments out over 3 months 139.00 for each for 4 drivers, and about 100 bucks each for finished boxes that I build. Grand total of 1114.00 for two subs flat to 18 or lower.

WmAx said:

Which Ashly stuff is class A? Class is the most inefficient class of operation. No way could Ashly compete in the business if they had to implement thermal dissapation and power supplies that are several times the capacity as required by other operation classes.

-Chris

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All of 'em.
http://www.proaudiosuperstore.com/ashly_amplifiers.html

jeffsg4mac said:

The A500 will do 500 watts mono into 8 ohms. More than enough to drive dual 10's and only 179.95. American musical will let you spread those payments out over 3 months

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Optimistic specifications on Behringer's behalf. Actually it's 360 watts @ 8 ohm bridged with no clipping, or 440 watts bridged @ 8 ohms, at 1% THD.

-Chris

zumbo said:

http://www.proaudiosuperstore.com/ashly_amplifiers.html

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I promise you, not one of those features a class A output power amplifier section. From their descriptions, they refer to class A 'driver' and 'front end'. That just means the line level input buffer is class A. Not the power amplifier section. Realize, that a class A amplifier is 25% efficient.

-Chris

zumbo said:

Yes. I have the Adcom. Jamming some Days of the New at the moment. I was not planning on changing my current set-up, but was beginning research for a 2-channel(music only) system. Then that Butler amp was listed on another thread. So, after all the goo goo I have seen and heard about tubes, I wondered if my current 5.1 should evolve, instead of a seperate 2-channel system. Anyway, I dream of some B&W 801's powered by something.

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Well there is something to be said about listening to some nice music in the dark with the warm glow of tubes. I don't know if I would use 801's though.

Here is tthe perfect tube setup IMO

http://cgi.ebay.com/Klipsch-Heresy-II-Speakers-Sequenced-Pair-Match_W0QQitemZ5848894330QQcategoryZ61378QQrdZ1QQcmdZViewItem

Or
http://www11.plala.or.jp/se_ke5583/JBL/speaker/l101lancer.html

Then you need a couple of these:
http://cgi.ebay.com/2-MCINTOSH-MC60-MONO-TUBE-AMPS-CONSECUTIVE-SERIAL-NOS_W0QQitemZ5847024632QQcategoryZ73371QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Finally one of these:
http://cgi.ebay.com/McIntosh-C-11-Stereo-Tube-Preamplifier_W0QQitemZ5848390122QQcategoryZ67807QQssPageNameZWDVWQQrdZ1QQcmdZViewItem


Now that is a tube system!

WmAx said:

Optimistic specifications on Behringer's behalf. Actually it's 360 watts @ 8 ohm bridged with no clipping, or 440 watts bridged @ 8 ohms, at 1% THD.

-Chris

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Still plenty for a sub, and probably much better then a so called sub amp designed to mount in the back of a sub. Bash, etc.

WmAx said:

I promise you, not one of those features a class A output power amplifier section. From their descriptions, they refer to class A 'driver' and 'front end'. That just means the line level input buffer is class A. Not the power amplifier section. Realize, that a class A amplifier is 25% efficient.

-Chris

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They say
The MFA-Series utilize the latest design parameters for Mos-Fet power devices. All power and gain stages use discrete, full complimentary, class-A circuitry for very low distortion and clean overload behavior.

I am not educated on amp "class", so pardon my ignorance. Learning.

zumbo said:

They say
The MFA-Series utilize the latest design parameters for Mos-Fet power devices. All power and gain stages use discrete, full complimentary, class-A circuitry for very low distortion and clean overload behavior.

I am not educated on amp "class", so pardon my ignorance. Learning.

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Then that is a typo or they lie. It's not physically possible for their MFA-Series amps to deliver their rated power if they are Class A. In fact, the MFA-Series must be switching amplifiers to deliver their rated power output(and the MFA-800 would have to be driven by a 240VAC line even then, to produce it's rated 2 ohm output capability).

-Chris

WmAx said:

Then that is a typo or they lie. It's not physically possible for their MFA-Series amps to deliver their rated power if they are Class A. In fact, the MFA-Series must be switching amplifiers to deliver their rated power output(and the MFA-800 would have to be driven by a 240VAC line even then, to produce it's rated 2 ohm output capability).

-Chris

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Why would a respected high-end pro-gear company lie about their specs? This isn't Bose.


http://www.ashly.com/
http://groups.msn.com/barley/frontdiffoilseals.msnw

I don't care to speculate on the typos or lies(which ever they may be).

Zumbo, here are some basic physical rules....

I(current in amperes)*V(voltage)=P(power, in watts).

A standard home line is 120V*15 amps = 1800 watts. The heaviest capacity 120V line allowable by elecrical code is 120V*20 amps = 2400 watts.

Each amplifier class has a typical efficiency approximation. A percent of the total power that it can turn into output power. Here is a breakdown:

Switching Amplifiers:85%-95%
Class AB: 50%
Class A: 25%

To get the rated 2 x 800 watts @ 8 ohms of the Ashly MFA-800 claims, if it was class A output stages, it would have to consume 6400 watts. Not possible from a 120VAC line. But that is only the beginning of the consideration. A Class A amplifier also produces far more heat than any other class, and it(unlike other classes which only disapate in proportion to the power being actually output from the amplifer) disappates the full wasted percent of energy 100% of the time. So that means you have a 4800 watt space heater in case of the MFA-800. The heatsink/cooling solution would not even fit in the case size of the MFA-800, and the power supply alone would be as big as the entire case. In fact, in AB operation, it could not produce 800 x 2 from a 120VAC house line. It must be a switching amplifier to reach even this spec with continous power output.

-Chris

EDIT: Corrected number of channels of MFA-800.

WmAx said:

I don't care to speculate on the typos or lies(which ever they may be).

Zumbo, here are some basic physical rules....

I(current in amperes)*V(voltage)=P(power, in watts).

A standard home line is 120V*15 amps = 1800 watts. The heaviest capacity 120V line allowable by elecrical code is 120V*20 amps = 2400 watts.

Each amplifier class has a typical efficiency approximation. A percent of the total power that it can turn into output power. Here is a breakdown:

Switching Amplifiers:85%-95%
Class AB: 50%
Class A: 25%

To get the rated 800 watts @ 8 ohms of the Ashly MFA-800 claims, if it was class A output stages, it would have to consume 3200 watts. Not possible from a 120VAC line. But that is only the beginning of the consideration. A Class A amplifier also produces far more heat than any other class, and it(unlike other classes which only disapate in proportion to the power being actually output from the amplifer) disappates the full wasted percent of energy 100% of the time. So that means you have a 2400 watt space heater in case of the MFA-800. The heatsink/cooling solution would not even fit in the case size of the MFA-800, and the power supply alone would be as big as the entire case.

-Chris

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So, are you saying AB is the way to go?

zumbo said:

So, are you saying AB is the way to go?

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I am not endorsing a particular class of operation. Today, you can find good examples of any class of operation.

-Chris

I am shocked...yes, shocked!...that no one, not even Chris, mentioned one of the most compelling advantages of tube amps:

They do double duty as space heaters! Maybe even as hot plates. I have heard that you could fry an egg atop a Pass Aleph. Just the thing when you're in the doghouse with the Mrs...