Pairing Audiolab 8000 A with P dillemma

[admin_exported]

Hi,

I recently acquired a 8000P to partner my 8000A (both early models) and am struggling to hear any appreciative benefit over the A in isolation.

I initially tried wiring all to the 8000P - and this plays ok. But when I try running the HF through the A and LF through the P - there is no difference...? should there be???

Also, in this configuration, when I turn off the P (whilst playing) again there is no difference and I still hear LF coming through the A?????

Am I doing anything wrong??

thanks

 

[WinterRacer]

Hi, sorry if you already know this. Your speakers will need two pairs of binding posts per speaker and the links that normally connect these links should be removed. You then need to connect the 8000a to the left and right HF binding posts and the 8000p to the left and right low frequency binding posts. If done correctly, turning off the 8000p should mean no bass.

Note, this isn't the only way to connect your system, but if you want to bi-amp, it's what I'd recommend.

Hope this helps.

 

[Anonymous]

Many thanks for this.

My speaker cable is 2>4 RCA though. So in this instance I'd only need to route to either the - for LF or + for HF?? or will I need 4>4 as per your diagram.

thanks

 

[WinterRacer]

Hi, I'm not quite sure I understand your question. Do you mean your speaker cables have two connectors at one end and four at the other? If so, you've got speaker cables for bi-wiring, not bi-amping. You need to set it out like the diagram with four cables (at both ends) for each speaker. In other words +Ve and -Ve for high frequency and +Ve and -Ve for low frequency, this is for each speaker.

 

[Anonymous]

looks like I need some new cables then. Thanks for your help

 

[gregvet]

I can't say for sure with your cables, but I bought some chord epic super twin that was terminated 2-4, and they were able to reterminate it 4-4 for me at the shop. At the '2' end the two positives are currently wrapped together and both joined with the banana plug, same for the negative wires.

So most likely your current cable can be reterminated to allow what you need without buying a whole new cable.

 

[WinterRacer]

Yes, what gregvet wrote. With lots of connectors very easy to do yourself or should be cheap from your local dealer if you don't want to DIY.

 

[John Duncan]

+1. If it's four-conductor cable they sound like they've been terminated at one end to do biwiring rather than biamping. Split them and put banana plugs on both sets. Run one set from the integrated and one set to the power. Usually the more powerful one should got to the LF drivers; will check and see if the A and P have different power ratings...

EDIT - I'm sure there have been loads of different versions so can't be definitive, but seems 60w a side for the A and 100w a side for the P, so use the P for the LF drivers.

 

[WinterRacer]

As and Ps do have different power ratings, but the same gain. In a normal 2 way speaker the tweeter takes hardly any power so use the 8000p alone until you get your cables reterminated. If you get your cables reterminated do as JD suggests and use the A for the tweeters.

One word of caution, you may not notice any difference when adding the A over the P alone - I didn't with the various speakers I've used.

 

[Anonymous]

thanks

Would you recommend that I just stick with powering everything with just the 8000P then and not bother with bi amping if the audio benefit is marginal?

 

[WinterRacer]

thanks

Would you recommend that I just stick with powering everything with just the 8000P then and not bother with bi amping if the audio benefit is marginal?

Yes, that's my experience with the speakers I've used. However, if you've got complex 2 way speakers with multiple drive units, you might get different results, in other words, if the LF and HF both require significant amounts of power there should be benefits.

Given you've already got the A and the P I'd still recommend trying it for yourself - others claim significant benefits and I might just have cloth ears!

 

[Anonymous]

In reality, biamping is only worthwhile if you have an active crossover splitting the signal before the amps otherwise there's no real difference.

A crossover works by using capaciance and inductance to passively filter out either the low or high frequencies from a signal (and convert the waste energy into in heat). In normal operation a single signal is split by the xover and sent to the high or low frequenciy drivers as appropriate, given a relatively normal xover point you can expect about 90% of the music power to go to the mid/bass and 10% to the tweeter.

Now, imagine you have two full range signals from separate amps, one being fed to the mid/bass terminal and the other to the tweeter terminal, as what happens when you bi-amp. The signal to the mid/bass goes to the crossover and the treble gets filtered out (and converted to heat - wasted energy) resulting in 90% of the power being retained. The signal going to the tweeter then gets the mid/bass filtered out and you lose 90% of that power.

So, what have you achieved? neither amp is benefiting from working on a 'cleaner' signal as they are both amplifying full range so you get nothing there. The mid/bass amp is wasting 10% and the treble amp is wasting 90% of its effort, nothing to be gained here either. Neither drive unit is seeing anything different, nothing of benefit here either.

So why bi-amp with passive xovers? beats me.

Using active xovers BEFORE the amplification is a different matter, as any Meridian owner will probably tell you.