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That had to be LOUD. Or as the old man said "too damn loud"...but how many cubic feet is your listening room? The meters were pegged? So the average level was very high and peaks were engaging the power guard?

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2 hours ago, babadono said:

That had to be LOUD. Or as the old man said "too damn loud"...but how many cubic feet is your listening room? The meters were pegged? So the average level was very high and peaks were engaging the power guard?

 

It was bonkers loud and I rarely play it at that volume. Meters were pegged and power guard kept flashing :) 

 

Sometimes it's fun, lol.

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2 hours ago, babadono said:

Your Mac at 250 W RMS output power is pretty close to the max allowed into the LF cabinet...just sayin'

I'd like a McIntosh whose volume knob goes to 11 :)

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I hate Class D these days... Convenient? yes... Quite? yes... Damping? yes... Powerful? yes... I still dont like them that much.

 

do I use them? yes...

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2 hours ago, Schu said:

I hate Class D these days... Convenient? yes... Quite? yes... Damping? yes... Powerful? yes... I still dont like them that much.

 

do I use them? yes...

This is a very interesting statement...why do you hate Class D if they are to your point, convenient, quite, damping, powerful...

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Which impedance output tap are you using on the Mac? Have you tried others?

Spec sheet says there is an impedance dip to 3.5 ohms at 160Hz.

You could buy another and run them bridged..500 W a piece...I love to spend OP's money:D

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3 hours ago, Schu said:

I hate Class D these days... Convenient? yes... Quite? yes... Damping? yes... Powerful? yes... I still dont like them that much.

 

do I use them? yes...

Like a guy who says he hates condoms: "but I use them twice a day."

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2 hours ago, babadono said:

Which impedance output tap are you using on the Mac? Have you tried others?

Spec sheet says there is an impedance dip to 3.5 ohms at 160Hz.

You could buy another and run them bridged..500 W a piece...I love to spend OP's money:D

 

Great question and this what the wise and kind @mikebse2a3 suggested privately! I tried both 4ohm and 8ohm taps yesterday for a casual (but not loud) listening session but did not run the music up to 105db; I'll give that a whirl and let you know what I discover. I was using the 8ohm tap in the previous test.

 

WRT another MC252, I am fortunate enough to have two here :) I might run that test as well and see what happens with an MC252 dedicated in mono to each channel. 

 

BTW, using the 4ohm tap (instead of the 8ohm tap) in my casual listening session resulted in a softer bass thump from the Jubilee speakers. Switching back to the 8ohm tap sounded better and more powerful. I can see where listening to jazz or something that doesn't really need that tight thump might be better with a 4ohm tap connected to the LF cabinets.

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Getting more voltage out of the 8 ohm tap than the 4 for sure. I'll bet @Chief bonehead would say it is a nominal 8 ohm load use the 8 ohm tap. But I have been wrong before:)

On my UG Jubes at absolute ear splitting levels I MAYBE at 10 W with say 10dB peaks above to 100W into the bass bins (on a great recording). Again I must say that had to be "too damn loud". My room is approx 9400 cubic feet.

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3 hours ago, babadono said:

Getting more voltage out of the 8 ohm tap than the 4 for sure. I'll bet @Chief bonehead would say it is a nominal 8 ohm load use the 8 ohm tap. But I have been wrong before:)

On my UG Jubes at absolute ear splitting levels I MAYBE at 10 W with say 10dB peaks above to 100W into the bass bins (on a great recording). Again I must say that had to be "too damn loud". My room is approx 9400 cubic feet.

 

You want to know something embarrassing? When I got the Heritage Jubilee speakers, I didn't ever bother to notice that the HF horns have a 16ohm nominal impedance. Yesterday, I switched them from the Mc225 8ohm taps to the 16ohm taps and the sound was clearer/brighter (but not sharper). Did it sound pretty good using the 8ohm taps on the MC225? Yes. Did it sound pretty good using the default taps on the J2? Yes. 

 

You asked about the room size; here is the exact config. Speakers are on either side of the french doors in the family room. Floor is concrete with thick padding/carpet. Back and side walls are concrete retaining walls. 

image.thumb.png.ec98da172aa376c1a61e93f2b2705af6.png

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FWIW, 

 

I run a set of Heresy 1.5's and also a pair of KP-301's. 

 

To this point, the sources have been:  

NAD C328 (50 WPC, class D) May be 3-4 years old

Cambridge Audio (100 WPC class D) about 3 years old

Onkyo TS-SR805 (130 WPC not sure of class frankly) mebbe 10-12 years old

Dayton audio DTA2-1BT2 (50 WPC class D) 3 years old

NAD 2200 (150 WPC class AB) at least 35 years old

 

They all sound ok at low levels, but the 2200 just sounds better- I swear it sounds like the amp is just loafing until I hit the point where I cannot stand to be in the room.   

 

 

 

Given the efficiency numbers of the speakers esp. the -301's, 50 WPC "should" be more than enough to run me out,  and they get loud but are not fun to listen to- they just sound like they're being pushed.  It's like a small turbo 4 cylinder running hard vs a big V8 loafing just over idle.  

 

I suffer hearing loss above 10 Khz, and am blessed with a nice case of tinnitus so I am not a great authority to be sure, but I know what I like and class D doesn't do it for me. 

 

Before anyone goes there, yes, I know these are not apples to apples so feel free to to toss out everything I say. 

  

Edited by MrT58
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16 hours ago, kippy said:

You asked about the room size; here is the exact config

Ahhhh  I see you are blessed with an odd shaped room just like me.:D It is kind of hard to make out all the measurements/. Have you ever computed the cubic footage?

I posted my room dimensions here:

 

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6 hours ago, babadono said:

Ahhhh  I see you are blessed with an odd shaped room just like me.:D It is kind of hard to make out all the measurements/. Have you ever computed the cubic footage?

I posted my room dimensions here:

 

I will read through you thread and adventure. Room is 660SF, 8' ceilings so I think about 5280 cubic feet

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