Focal Grand Utopia Bi-amplified by Pass Labs X250.5?

[mert]

Dear Nelson,

This time I am seeking help for a despirate fellow audiophile. He has Focal Grand Utopia be, Boulder 1050 monos, 2010 pre amplifier, Meridian 808 Cdp. He has a major problem of driving these speakers since Boulder 1050 monos(500 watts in Boulder Watt , don't take Boulder specifications seriously) can't drive sufficiently and gives you a strong feeling of absence of bass.
This guy wants to drive bass with X250.5 together with Boulder 1050 monos.(mids and highs) I would like to learn your idea and suggestions. Plus can there be any drawback of this configuration?

Regards

Mert Tetik

[Nelson Pass]

Boulder does not have a reputation for failing to meet specs -
perhaps there is another problem.

Having said that, I don't see any drawbacks. You only have to
see to it that the levels are adjusted between the two amplifiers.

[mert]

Originally posted by Nelson Pass
Boulder does not have a reputation for failing to meet specs -
perhaps there is another problem.

Having said that, I don't see any drawbacks. You only have to
see to it that the levels are adjusted between the two amplifiers.

can you be more specific? How can we adjust the levels of both amplifiers? or what figures we have to look for in order to obtain matched level?

[Nelson Pass]

Normally you want to be able to adjust the relative gain between
the amplifiers. It is not enough that the gain might be matched,
becuase you inevitably want to play with it. A simple attenuator
on the amplifier which has more gain would do the trick.

[bobsinclar]

Why try to biamp this speaker? it has a sufficiently complicated internal crossover that hardly tries to make all the speakers sound with coherence...if you bi amp you are just adding complexity to the whole system, and ajusting levels is part of the problem, because amps may have diffrent gains whatever power they can deliver...without mentionning any other specificities ...
Vince

[GRollins]

Originally posted by mert


He has a major problem of driving these speakers since Boulder 1050 monos(500 watts in Boulder Watt , don't take Boulder specifications seriously) can't drive sufficiently and gives you a strong feeling of absence of bass.

Any chance the woofers are connected out of phase?

Grey

[mert]

No, it is not the case. We have tried to drive with Meridian G57 power amplifier but didn't work out. Nelson is right. Maybe just pass labs amplifiers can make this setup sound ''right'': XA160.5+X600.5

[bobsinclar]

Nelson Pass is known as the best of the best, but he is not superman...trying to get these speakers to work coherent with good imaging and strong bass is a job for god!
Just kidding...but it's just that each time I listen to it i just ear speakers playing independantly , not a real fusion between them

Pass amps can drive anything , if it doesn't work fine then you'd better suspect the speaker rather than the amp connected...
grey gave you a start point...you could also look at the crossover if there is a switch for adjustment or anything inside that isn't working as expected...

[tinitus]

Originally posted by bobsinclar
Why try to biamp this speaker? it has a sufficiently complicated internal crossover that hardly tries to make all the speakers sound with coherence...if you bi amp you are just adding complexity to the whole system, and ajusting levels is part of the problem, because amps may have diffrent gains whatever power they can deliver...without mentionning any other specificities ...
Vince

I agree with bob, coherence may suffer with biamping...unless you want to establish something that wasnt there from the beginning...as Nelson suggested, turn down the gain on the amps driving mid/high

[Nelson Pass]

Actually, guys, I said "I don't see any drawbacks". I didn't mean
to suggest that it was necessarily a solution.

If it was my speaker and I wanted to fix it, I would probably
tear out the crossover and spend a year or so tweaking up a
new one.