Is Bi - amping worth the trouble?

Why not put all the money In a ecxellent stereo amplifier, instead of several lesser units with signal degrading from external crossover units.

Mfontana
Good to hear. those 5's are way more sensitive than the 4JR's though, aren't they? that following post makes sense too... eliminating some path and resultant obstacles should have provided for more gain... I'll keep those rothwell attenuators in mind too.

Hiend2
that's a good question. Actually i'd like to have an idea of just how much a signal is degraded period. by anything... and just how much can a signal be degraded before it is audible? ...and are we sure that a signal is being degraded, in the first place? or is only X overs the culprit for signal degredation?

Personally, i think otherwise. if this tact has worth... the signal begins at a source. let's say a digital source. let's say the signal is at it's best after all the D/A conversion is done... that's the output terminals. then would cables play a part in signal degredation too? oK, how much?

I hear that term bandied about frequently. From personal experience, in cable applications, everytime a connection is employed in the signal path a resultant loss of approximately 3db occurrs. Depending upon the initial signal level, 3 db isn't much at all. minimally in regular setups, given the above... 12 to 18db loss is occurring. Now if there is loss, then isn't the signal being degraded? Loss equates to degredation. Distortion, now, there is perhaps a more apt term. i believe many confuse the one with the other... and use them interchangeably. then it would stand to reason a one piece unit without additional peripherals and connections 'should' (if comparably build quality is incorporated), be best. integrated units should take the lead... I think 'separates' are in that position, however.

All in all, there is no such thing as a perfect system or plan, if humans are involved. As to the above poster, 'perfectionist', I too am a perfectionist... with a poor track record... so I gave up on that path and decided to be extremely good, and most often, 'just above average', I can live with that quite easily. there is more time for listening, and enjoyment, and oh, yeah, there's that 'fun' aspect of it all too.

Perfectionist: Given the fact that you're using mono-blocks, you wouldn't be vertically or horizontally bi-amping. You would simply be bi-amping with mono-blocks.

Blindjim: How did you arrive at the figure of 3 dB? At radio frequencies, every connection added is a supposed .5 dB loss according to common teachings. In my experience, a good connection doesn't lose anywhere near that much. At audio frequencies, i'm quite certain that the loss is noticeably less.

Having said that, connection losses may not be linear in amplitude as frequency is varied. On top of that, other distortions may occur as a result of added connections. Obviously, the quality of connection will have a lot to do with how much loss is involved. The greater the variances between terminating impedances, the greater the loss and potential for increased distortion. Needless to say, part of "cable swapping" is a combo of all of the above, which partially explains some of the variable results we achieve in different systems.

I've often contemplated what would happen if one were to take a distortion analyzer and measure an entire system from source input cabling to speaker output cabling. After baselining the system as one normally runs it, one could then swap individual cables and re-run the same tests. I think that the comparative results would be very interesting to say the least. It would also be interesting to see how the system as it was would sound compared to the system as it measured lowest in distortion.

Obviously, one could conduct such testing component by component, swapping cables until the lowest distortion was achieved. From there, the next component and cable could be installed, taking the same approach. One could repeat this until the entire system had been pieced together using this approach.

Using this method, the cables would be acting as impedance matching transmission lines. Each cable would be fine tuned for the specific electrical interaction between the mating components that they joined together.

There's a LOT to think about on stuff like this. Quite honestly, i'm surprised that nobody has done anything like this and / or published research on this subject. Then again, most AF engineers don't think about cabling acting as a "transmission line". Could be why the subject has never been looked into that thoroughly.

Other than that, there are great sonic advantages to be had going "direct drive" i.e. no caps, resistors, inductors between the amp and speaker. Most of the guys messing with "full range" drivers know and realize this, but most of the "audiophile world" are clueless in this specific area. Sean
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Quite honestly, i'm surprised that nobody has done anything like this

Sean, FM Acoustics does this -- but for tis own products.

As you note, the designer hasn't published anything on this.

BUT, if you buy a complete system from FM (i.e. electronics + cables), that whole transmission line is optimised.

You can even buy speakers (made by someone else ASAIK) similarly "optimised" for the FM amp + spkr wire used. HOWEVER, I understand that the recommended solution is active multiamping... of course, one can order the spkrs with a passive xover in which case the spkr cable supplied is different (obviously).

So, the transmission line is purportedly optimised starting at the source output cable. Since FM's preamps allow some variability in their input impedance, this line can be tweaked soemwhat further upstream.

One snag is, the wires must be specific in lengths (apparently a small variability is OK). Another is the cost -- $~+10-15k per component: this may not look ruinous for some, but for a vinyl addict doing the simple maths, it adds up: Pre + phono+power amp = $+~40k. The cost of cables is minimal apparently:)
Oh yes, I forgot: you also need spkrs...

Oh yes: I actually listened to such a system, vinyl source -- with different spkrs. Admittedly, impressive, very impressive.

"Why not put all the money In a ecxellent stereo amplifier, instead of several lesser units with signal degrading from external crossover units."

First of all it is my impression that there are no Excellent stereo amps, excellent would apply only to mono amps...
What would a lesser or excelent amp be?
An excellent amp with 8 tubes per side on push pull? Thats a lot of tubes, and they do sound like it...IMNSHO a pair of pushpull tubes is best smaller is better then.
Also you get more power supplies with 4 monoblocks that with one stereo amp. I have even seen diagrams (and almost tried one) of one amplifier with a power supply per stage of amplification....that would make it 8 power supplies against...well one.

What we are also trying to avoid is the internal Speaker Xover and use line level XO inside each amp....cool!!

Do Bi-amp