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MC275 single/pair vs. MC75 pair ?

ofery

ofery

Active Member
Hello All,

I'm going to buy a new Mcintosh pre+power.
I have decided to buy the new reissue C22 as my Pre.
Now I have to decide on power - new MC275 VI or new reissue MC75 ?
Which combination is preferred: one MC275, pair of MC275 or pair of MC75 ?
Is there any hardware or audio limitation or any other concern to connect pair of mono MC275 ?
My speakers are: JBL L250TI - 90dB efficiency.

Regards /Ofer
 
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ofery said:
Hello All,

I'm going to buy a new Mcintosh pre+power.
I have decided to buy the new reissue C22 as my Pre.
Now I have to decide on power - new MC275 VI or new reissue MC75 ?
Which combination is preferred: one MC275, pair of MC275 or pair of MC75 ?
Is there any hardware or audio limitation or any other concern to connect pair of mono MC275 ?
My speakers are: JBL L250TI - 90dB efficiency.

Regards /Ofer
Click to expand...

My suggestion would be to get an MC275. Not only is it less expensive than 2 MC75, but the MC275 may be configured to a 150 watt monobloc itself. Thus giving you the option of adding another MC275 (for 150 wpc) at a later date if you so choose, otherwise you'll have to swap out the MC75s entirely should you desire/need additional power.

I doubt whether anyone can discern between a pair of MC75 and MC275 in a controlled A/B test.
 
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Both will work. MC75 will cost more since they are two chassis but they are also very cool, mono blocks so you will have maximum separation with the MC75s. Two great tube amps for sure.

thanks,
Ron-C
 
62caddy said:
My suggestion would be to get an MC275. Not only is it less expensive than 2 MC75, but the MC275 may be configured to a 150 watt monobloc itself. Thus giving you the option of adding another MC275 (for 150 wpc) at a later date if you so choose, otherwise you'll have to swap out the MC75s entirely should you desire/need additional power.

I doubt whether anyone can discern between a pair of MC75 and MC275 in a controlled A/B test.
Click to expand...

Umm...so I started typing and then I read this. No need for me to say anything else. :)
 
If cost & power are out of the equation, which option will give a better sound ?: One MC275, Two MC275 or Two MC75 ?

Regards /Ofer
 
If it were me and I knew that 75wpc was going to be more than adequate for my needs, I'd go for the MC75 monoblocks.
Otherwise, the '275 for future expansion if staying Mac tubes.
 
ofery said:
If cost & power are out of the equation, which option will give a better sound ?: One MC275, Two MC275 or Two MC75 ?

Regards /Ofer
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At the same volume level, they will sound so close to identical that I urge you to actually test it as I can virtually guarantee that you won't hear the difference.

The only difference is how loud you can push things. Your speakers are 90dB efficient--reasonable; but, not at all "high efficiency."

If we assume that you're sitting about 10 feet away from the speakers:

75wpc will get you a maximum of 102.1dB. If you are using these speakers for home theater, that's not going to be enough power to hit "reference level" of 105dB.

150wpc will get you 105.1dB--so just enough for reference. A reasonable approximation is that you're going to gain or lose 1dB per foot closer or further away (its actually 3dB / meter--but no need to get too scientific). I've heard Dan (4-2-7)'s L250s powered by monoblocked MC275s, MC501 mono blocks, and an MC402. I know his general assessment with the MC275s was that he wanted more power (hence the MC501s).

Those speakers are quite good and capable of some serious output. If you're set on tubes, go with a single MC275 to start. It gives you the most flexibility to move up. If you're not set on Tubes, something in the 300-400w range is probably a more ideal match. I personally have the problem of wanting tubes and running Martin Logan speakers. The only thing McIntosh makes that could work are MC2301s--and that's just not happening. :P
 
You could always bi-amp two MC275 per channel, where you would use a total of 4 MC275s for a two channel setup. :)

Or.... You could buy a newish Corvette. Lol
 
Lets see, since I have almost what you have and want to do.

Your L250s need more power than any of the tube combos you want to dive them with. Will they work? hell yeah!, Will they sound good? hell yeah!

However the 250s like and respond far far better with 400+ watts hitting them.

ofery where do you live? If your near me you can have a listen.

I have the non Ti L250s and it's magic what the MC501s did to them and that was after trying the MC402. So I would find used 501s or 601s or new 601s.

BTW
The new MC275 is really 90wpc, so Mono blocked it's 180WPC
 
Agreed with Nalthien's comments.

"Efficiency" is not always as simple as it seems: If, for example a speaker is 90 dB down to 20 Hz - that might be the way it tests in an anechoic chamber with an SPL meter but in practice, 20 Hz is not as easily registered by the human ear. Therefore that speaker will take a lot more power for the same perceived loudness that a speaker of the same sensitivity with a low limit of say 40Hz.

I finally made this determination when - for a while - I was unable to figure out why a 90 dB Polk RTi A9 sounded nowhere near as loud as other 90 dB speakers I have.

The simple fact is that tubes are not nearly as good at generating amperage as solid state electronics and 90% of amplifier power is consumed reproducing the lower frequencies. The lower the frequency, the more power is needed to reproduce it.

While there are some high powered tube amplifiers nowadays for those who insist on tube equipment but the $/watt is just not cost effective, to say nothing of the cost of maintenance. Tubes driven hard will need replacement far more often than those that are loafing along with high sensitivity horns at <1 watt with the occasional 10 watt peak.

That JBL model is much better suited to a large McIntosh solid state amplifier in order to take advantage of its capabilities, IMO.
 
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For the life of me I can't understand why mac even came out with the mc75s. They don't even give you all that the mc275s do, cost almost the same. If you want mono block tube power your better off bridging the 275 and still have more power and options in using them alone as well. Buying the 75s your done thats it no other options,
 
4-2-7 said:
For the life of me I can't understand why mac even came out with the mc75s. They don't even give you all that the mc275s do, cost almost the same. If you want mono block tube power your better off bridging the 275 and still have more power and options in using them alone as well. Buying the 75s your done thats it no other options,
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I suspect the MC 75 was relatively inexpensive to design & manufacture since so much is shared with its stereo sibling MC275. Many people do not realize an MC275/240 is really just two MC75/MC40 on a single chassis.

Cheap (for Mac) to build, plus take advantage capturing the part of the market that prefers monoblocs - it's really a no brainer from a business standpoint.
 
4-2-7 said:
And no more than a gimmick for yupies....:p
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"You may very well think that; I could not possibly comment..."
Whissle.gif
 
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I have found with my old ass ears that really mac new tubes amps have the mac sound and mac SS amps are so worm with that Mac sound it really doesn't matter. If you need power go SS and you already have the tubes in the Preamp anyway.
 
4-2-7 said:
I have found with my old ass ears that really mac new tubes amps have the mac sound and mac SS amps are so worm with that Mac sound it really doesn't matter. If you need power go SS and you already have the tubes in the Preamp anyway.
Click to expand...

+1 for this suggestion! My C2300 / MC452 combo is awesome. :D
 
Going on what precedes here, if I wanted good powerful sound without the uncertainty of long term peak performance from tubes, I'd take Dan's advice and go large with solid state power.
For myself as a small scale audio hobbyist, I'd like to live with a pair of MC75 monoblocks for a while.
 
damacman said:
Of the options you've listed, I think I'd choose the pair of MC275. That offers you the most power, the most flexibility, and the most tubes glowing in the dark.
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And a big bill to change out all those tubes, let alone the heat they put off in the summer time.
ofrey do you have air conditioning? I really don't use my tubes on hot humid days at all.
 
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