Mac's BAD MATCH for 802D's?

You will not damage your speakers Larry and you should try it. I am not the foremost expert on this, but having owned N803's and 802D's, McIntosh told me to use the 4 ohm taps with these B&W's.

Someone can correct me if wrong, but the advantage of these different taps is for better impedance matching with your speakers and although B&W states these speakers in question as 8 ohms, they behave more like 4 ohm speakers, yes?

Yes. The problem is, from an amp's perspective, low impedances are hard to drive - not the high ones. Many (conventional dynamic box) speakers have a low impendance in the bass and a high impedance in the upper mids and highs. The average is a very rough 8 ohms so that is what is published in the manuals and brochures.

However, all the amp really sees is that 4 ohm bass impedance! So technical people will say, use the tap that corresponds to the lowest impedance of the speaker. In 90% of cases today this is about 4 ohms - especially true for B&Ws.

In the old days, speakers had a much higher impedance. There are several complicated reasons for this but to keep it short, they would often average 8 or even higher. If you look at old tube amplifiers, they all have 16 ohm taps and some even have 32 ohm taps! With the advent of cheap high-power solid state amplifiers in the 1970s, speaker designers gained some freedom and have since settled on a much lower typical impedance curve (again, for many reasons). This is why modern tube amplifiers only have 4 and 8 ohm taps - 16 ohm speakers are basically extinct and REAL 8 ohm speakers are not far behind.

Arthur

Brianmgrarcom you are correct about what you said, most people don't know this.

I dropped by my freinds who I had mentioned in my first thread who has the Mac 501's and 2200 pre. with the 802D's. Well a freind of his was over and they had a Mac 1000 pre hooked up, unbeleivable. I have a VTL 7.5 and Audio Research Ref3 that I am going to be bringing them over to do a comparison. I couldn't stay for long today so we all agreed to get together tomorrow and do the demo so my freind gets to listen to this 1000 all night. I have to say what I heard was the best I have ever heard his system sound like.

Tommorow will be real interesting.

John his friend has the new EMM all one piece cd player which I have been wanting to hear, I have a Audio Research Ref7 that I will be bringing along also with some cables of course.

Virtual Dynamics, Stealth Sextet digital, Anniv Purist Purist cables.

I really am looking foward to this, I actually want to go over and start right now.

I'll post again once done.

That is quite a line up of gear Dev and sounds like a fun time!

Well it wasn't just one day but two, now that was fun.

Alot of different sounds happening, we did blind test so the others listening would not know what was hooked up for two days and then finally sat arround still with some music in the back ground and dicussed the out come. We all had our note pads in which we kept track.

Well there wasn't really any dislikes except from the owner of the 802D's because he wanted us to leave our gear.

Regarding pre's WINNER #1 Mac 1000 #2 ARC REF3 #3 VTL 7.5

Sources: We could not agree on this, I picked the ARC every time but at the same time really liked the EMM. The owner of the EMM was also mixed and the owner of the 802D's was just so confused because he was so over whelmed with everything he heard. It really depended on which combination was hooked up but I have to say hats off to McIntosh for that 1000, it's now on my list to have.

Any questions, ask and I'll try to answer for you.