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Old 22nd November 2013, 06:33 PM   #1
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Default F5 + B&W DM683

Anyone who is following my thread about building a fully active Wilmslow Audio Prestige Platinum speaker pair will appreciate where I am going with this thread.

In order to tri-amp the WAPP I need six amplifiers.

I've got a DIY Pass Aleph 4 which is probably the best amplifier that I have ever heard. It effortlessly drives my old B&W 683s and sounds BRILLIANT.

In the tri-amp set-up I aim to use the Aleph to drive the Volt VM752 drivers as that is where there is the most information and the human ears are most critical.

I thought I would use an F5 to drive the Scanspeak R2904/7000.0 tweeters. The power requirement is low which suits the F5 and the load is fairly simple. There is no crossover as the Xover is active and before the amps.

Now, I've just hooked up the F5 to test it with the B&W 683s (all in full bandwidth), its playing music but the midrange is just flat and dead. The Aleph 4 is so much more vibrant and exciting to listen to.

I appreciate that the B&W are a complex load but I didn't expect such poor results.

With about 70000uF x 2 of cap in a single PSU I'm getting an almost inaudible hum at the speaker, I'm not too fussed about that as they will be driving tweeters.

Last edited by KatieandDad; 22nd November 2013 at 06:37 PM.
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Old 22nd November 2013, 06:35 PM   #2
ra7 is offline ra7  United States
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Before blaming the F5, tell us what you have for the preamp. The F5 needs a bit of gain.
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Old 22nd November 2013, 06:38 PM   #3
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Gain is not the issue. I've got a B1 which is attenuating the signal for normal listening levels.
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Old 22nd November 2013, 06:44 PM   #4
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Ah-hah! I'd say gain is your issue. You might want to substitute a preamp with some gain, and see how it sounds.
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Old 22nd November 2013, 06:54 PM   #5
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The CD player is outputting over 2V RMS which is more than sufficient to drive the F5. I need the B1 to attenuate the signal to normal listening levels. Taking the B1 out of circuit just drives the F5 to deafening level.
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Old 22nd November 2013, 07:58 PM   #6
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Quote:
Originally Posted by KatieandDad View Post
Anyone who is following my thread about building a fully active Wilmslow Audio Prestige Platinum speaker pair will appreciate where I am going with this thread.

In order to tri-amp the WAPP I need six amplifiers.

I've got a DIY Pass Aleph 4 which is probably the best amplifier that I have ever heard. It effortlessly drives my old B&W 683s and sounds BRILLIANT.

In the tri-amp set-up I aim to use the Aleph to drive the Volt VM752 drivers as that is where there is the most information and the human ears are most critical.

I thought I would use an F5 to drive the Scanspeak R2904/7000.0 tweeters. The power requirement is low which suits the F5 and the load is fairly simple. There is no crossover as the Xover is active and before the amps.

Now, I've just hooked up the F5 to test it with the B&W 683s (all in full bandwidth), its playing music but the midrange is just flat and dead. The Aleph 4 is so much more vibrant and exciting to listen to.

I appreciate that the B&W are a complex load but I didn't expect such poor results.

With about 70000uF x 2 of cap in a single PSU I'm getting an almost inaudible hum at the speaker, I'm not too fussed about that as they will be driving tweeters.
I would agree with your assesment when compared tot he Aleph 4. You must also consider that you have listened to the Aeph 4 long enough that it has shaped your desire in amps and the F5 is just something different. I felt like the F5T was a more enjoyable amp than the F5, but the BA3 trumps them both, IMO. I think based on your like of the ALeph, the BA series is a better bet. Still plenty of oomph for you.
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Old 22nd November 2013, 08:47 PM   #7
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I am with the gain comment! Just try it :-).
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Old 22nd November 2013, 09:21 PM   #8
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Sorry guys. The F5 simply does not sound like the Aleph amps, gain or no gain.
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Old 22nd November 2013, 09:43 PM   #9
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No, it doesn't. But it does not sound "flat and dead" either. Apart from gain, other things could be your sources, or the build itself.
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Old 22nd November 2013, 09:49 PM   #10
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Quote:
Originally Posted by buzzforb View Post
Sorry guys. The F5 simply does not sound like the Aleph amps, gain or no gain.
Did you see I say that? :-) You know me, nothing sounds like an Aleph for me... hope something will beat it soon :-)
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