Philharmonic Audio - 3-way open back ML-TQWTs designed by Dennis Murphy

[Dennis Murphy]

I totally agree, although many 3-Way designs or 2-Way will use another 3/4"-1" thick piece of Plywood or Hardwood as the Baffle to mount the drivers to. This certainly stiffens up the front of the enclosure to minimize any coupling of vibration from one driver to the others.

Do the Phil 3's have this extra stiff Baffle added to the front 3/4" MDF of the enclosures?

Now, with these types of Questions I need some more "Posting Thanks"...

You keep those cards and letters coming. The stock Phil's just use 3/4" mdf on the front baffles, although they are heavily braced fore and aft. I think increasing the thickness will increase shipping costs more than it will decrease vibrations, but we have doubled up the fronts on request. That will add a few $$$, of course, and several more for shipping.

 

[AcuDefTechGuy]

You keep those cards and letters coming. The stock Phil's just use 3/4" mdf on the front baffles, although they are heavily braced fore and aft. I think increasing the thickness will increase shipping costs more than it will decrease vibrations, but we have doubled up the fronts on request. That will add a few $$$, of course, and several more for shipping.

If increasing the baffle thickness improves sound quality, then it's worth it.

But I wouldn't want to increase thickness, bracing, mass, etc., just for the sake of doing it.

How does this relate to the recent article by Gene regarding building audiophile speakers?

Whatever Axiom is doing, we sure don't want any piece of that pie.

 

[GranteedEV]

If increasing the baffle thickness improves sound quality, then it's worth it.

Improves SQ on a consistently recognizable basis, or just that an improvement is measurable or audible under controlled conditions with the right choice of content?

 

[AcuDefTechGuy]

Improves SQ on a consistently recognizable basis, or just that an improvement is measurable or audible under controlled conditions with the right choice of content?

Both measured anechoically and everyday life SQ.

 

[DenPureSound]

You keep those cards and letters coming. The stock Phil's just use 3/4" mdf on the front baffles, although they are heavily braced fore and aft. I think increasing the thickness will increase shipping costs more than it will decrease vibrations, but we have doubled up the fronts on request. That will add a few $$$, of course, and several more for shipping.

I presume you have measured them with and without the thicker Baffles?

 

[Dennis Murphy]

I presume you have measured them with and without the thicker Baffles?

Well, I take frequency response measurements of every speaker I send out, but the thicker baffle won't show up there, at least not if the back of the drill hole is chamfered to eliminate any tunnel resonances. I don't measure vibration modes. If Stereophile ever reivews a pair, I'll let them do that.

 

[DenPureSound]

Well, I take frequency response measurements of every speaker I send out, but the thicker baffle won't show up there, at least not if the back of the drill hole is chamfered to eliminate any tunnel resonances. I don't measure vibration modes. If Stereophile ever reivews a pair, I'll let them do that.

DM, please help me understand this.

Why are the plots main output ref. at 75dB on the Ordinate, when the Sensitivity of the speaker is 85dB?

Does this make a difference in FR plots if 85dB was used instead of 75dB?

I noticed the Salk SongTowers at 88dB was measured using that level on the plots, and other speakers that the NRC measured in their full anechoic chamber.

 

[Dennis Murphy]

DM, please help me understand this.

Why are the plots main output ref. at 75dB on the Ordinate, when the Sensitivity of the speaker is 85dB?

Does this make a difference in FR plots if 85dB was used instead of 75dB?

I noticed the Salk SongTowers at 88dB was measured using that level on the plots, and other speakers that the NRC measured in their full anechoic chamber.

I just don't bother to convert the measurements to a 1m senstitivy level because it's a pain in the butt on Praxis, my measurement program. The levels you see are essentially meaningless.

 

[AcuDefTechGuy]

I just don't bother to convert the measurements to a 1m senstitivy level because it's a pain in the butt on Praxis, my measurement program. The levels you see are essentially meaningless.

So your measurements are from 2 meters out, and plotted at 2 meters out, instead of 1 meter out?

 

[GranteedEV]

So your measurements are from 2 meters out, and plotted at 2 meters out, instead of 1 meter out?

I don't know about dennis, but my ears don't like test tones louder than 85.

I think the only advantage to taking a higher SPL measurement is to test for power compression with burst tones in an anechoic chamber, although yes like the NRC you can get higher resolution to test for (pretty useless as-is) THD numbers.

 

[Dennis Murphy]

So your measurements are from 2 meters out, and plotted at 2 meters out, instead of 1 meter out?

No It's not that simple. Praxis does not automatically measure at the same drive level used for the sensitivity standard even if you measure at 1 meter (which I do, plus maybe 2 or 3 inches). You have to convert it afterwards. That won't change the profile of the response plot, so it adds no information about the accuracy of the speaker.

 

[woodsart]

No It's not that simple. Praxis does not automatically measure at the same drive level used for the sensitivity standard even if you measure at 1 meter (which I do, plus maybe 2 or 3 inches). You have to convert it afterwards. That won't change the profile of the response plot, so it adds no information about the accuracy of the speaker.

This means nothing for a peon like me....just have to take your word for it.

On the other hand, I heard from a reliable source, that you were considered the "Godfather" of speaker building......Do you have weapons too????

Nah, I am sure you don't, or you might have already nabbed some house builders by now!!!!

Well, it was time for me to stur things up anyway, this was getting way too technical!!!

Now for some real talk.......

I WANT MY SPEAKERS......ALL 4 OF THEM!!!!!!!

 

[Dennis Murphy]

This means nothing for a peon like me....just have to take your word for it.

On the other hand, I heard from a reliable source, that you were considered the "Godfather" of speaker building......Do you have weapons too????

Nah, I am sure you don't, or you might have already nabbed some house builders by now!!!!

Well, it was time for me to stur things up anyway, this was getting way too technical!!!

Now for some real talk.......

I WANT MY SPEAKERS......ALL 4 OF THEM!!!!!!!

The cabinets for the Philharmonic 1's and 2's are currently in New York waiting to go through customs. Then it's a short ride down I95 to the Wehawken Rd studios. You should have everything, including the monitors, in two weeks.

 

[AcuDefTechGuy]

I WANT MY SPEAKERS......ALL 4 OF THEM!!!!!!!

So you got 2 towers and 2 monitors?

What about a center speaker?

 

[woodsart]

So you got 2 towers and 2 monitors?

What about a center speaker?

That is correct 2 each, however I will wait til the center channel cabinets are made. I am not sure when they will be delivered in the US. I can do without one for awhile, probably need to start saving all my allowances first

Of course Dennis is driving distance from me, so that helps.

Ha Ha, knew I would get a rise out of him!!! However, I know he is not sleeping, not by a long shot, hardly a nap at this point, if I were a guessing!!!

Dennis also knows I am a patient man!!!

 

[Warpdrv]

Is there a picture of what the monitors look like ?

I haven't seen those as far as I recall...

 

[woodsart]

This is the monitor taken with the Philly 3, (just a quick snapshot Dennis sent me) with the Fountek and the 7' Seas shown with the .5 cabinet.

The larger .75 cabinet is 17"H by 10" wide 14.5 deep and by itself is 24lbs, (I think).

I wanted the .75 cabinet for more bass.

 

[AcuDefTechGuy]

This is the monitor taken with the Philly 3, (just a quick snapshot Dennis sent me) with the Fountek and the 7' Seas shown with the .5 cabinet.

The larger .75 cabinet is 17"H by 10" wide 14.5 deep and by itself is 24lbs, (I think).

I wanted the .75 cabinet for more bass.

I would just get another one of those bookshelf speakers for the center.

 

[DenPureSound]

This is the monitor taken with the Philly 3, (just a quick snapshot Dennis sent me) with the Fountek and the 7' Seas shown with the .5 cabinet.

The larger .75 cabinet is 17"H by 10" wide 14.5 deep and by itself is 24lbs, (I think).

I wanted the .75 cabinet for more bass.

Those should be sweet. How do the measurements look on them?

 

[woodsart]

Those should be sweet. How do the measurements look on them?

Mr. D. you are asking the wrong person!!!! but.....DM will chime in with the measurements!

ADTG......Dennis offered that to me, however, 17" would be too tall in our area on top of the entertainment center.