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Old 11th March 2007, 12:53 AM   #1
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Default Old meets new but can this be solved?

Hi all.. I am very excited to say I just purchased an Aleph 3 amplifier. I have a plan to use it in biamp along with one of my Threshold 400a amps to a set of Vandersteen 2ce's which have crossovers built-in..

Only one MAJOR problem... Mr. Vandersteen no longer recommends bi-amping (he used to and in the manual it is HIGHLY suggested).. these are some quotes from his Q&A forum..

QUESTION #1

"Romesh (1/8/07): Hi Richard, I'm a dealer in New Zealand, and having problems getting a valve amplifier to stably drive a pair of 2ce. When we run one VTL ST85 bi-wired into the 2ce everything work fine. When we try to bi-amp with a second st85 we find that when a amplifier channel sees only the tweeter load it becomes unstable and we see wild variations in bias. The same problem applies with either vertical or horizontal bi-wiring .When we measure the tweeter load using a standard multi-meter we get an open circuit, and when we measure the bass we get varying impedances. Very strange. Are you able to shed any light on the situation? Can you suggest a fix so that we get allow our client to bi-amp? We would greatly appreciate your help Best regards,

Answer: HELLO ROMESH, THIS IS A COMMON PROBLEM WITH SOLID STATE AMPLIFIERS BUT RARELY WITH TUBE AMPS. THE HIGH FREQ AMP IS SEEING THE X-OVER CAPS PROTECTING THE MIDRANGE AND TWEETER LIKE ANY SPEAKER. THIS BY ITS SELF WITHOUT THE RESISTIVE LOAD PRESENTED WITH THE WOOFER SECTION IN PARALLEL IS CAUSING THE AMP TO BE UNSTABLE. THESE AMPLIFIERS CAN NOT BE USED THIS WAY BUT SHOULD BE BRIDGED MONO AND BI-WIRED INSTEAD."

QUESTION #2
"David (3/27/06): I have read your FAQ on bi-wiring. My A/V Receiver, Arcam AVR300, a 7.1 unit, allows you to configure the LSB/RSB amplifier outputs to bi-amp the LF/RF speakers, in a 5.1 system, as follows: RSB amp ----> RF - HF drivers FR amp -----> RF - LF drivers LSB amp ----> LF - HF drivers FL amp -----> LF - LF drivers My LF/RF will be 2Ce Signatures, Subwoofer V2W. Is this possible with the 2Ce Signatures? Is bi-amping preferable to bi-wiring? Thank you.

Answer: HELLO DAVID, WE DO NOT RECOMMEND BI-AMPING BECAUSE MANY SOLID STATE AMPLIFIERS BECOME UNSTABLE WITH THE CAPACITIVE LOAD REFLECTED BY THE MID-TWEETER SECTION. WE DO HOWEVER RECOMMEND BI-WIRING IN THE 2CE SIGNATURE OWNERS MANUAL."


MY question..

Is there a way around this? I know the Aleph 3 is known to be an incredible stable amplifier.. Might it be safe to run bi-amped with these two exceptional class A amplifiers?

Does the Aleph 3 self bias? Would I need to monitor the bias of the 400a?

I think that if I can do this the sound is going to be incredible!

Thoughts?

thanks!

Joe
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Old 11th March 2007, 05:43 PM   #2
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Richard Vandersteen states that bi-wiring provides most of the benefit of bi-amping. Bi-amping according to him is very tricky and not done properly, you will loose the phase coherience/alignment that the speakers are famous for producing. He expressly states that you MUST use the exact same amps when you are bi-amping.

I have a pair of Vandersteen 2ce's driven by an Aleph30 in a bi-wired configuration, and the sound is simply astonishing. Friends and neighbors who come over and listen are dumb struck by the sound; the hugh sound stage, the imaging, and how authorative and musical the system is to listen.

Just use your Aleph 3, bi-wire it and enjoy! The 2ce's have a nominal impeedence of about 6 ohms. The aleph 3 will drive them louder than you will care to listen to at high levels. Plenty of power, and you will very unlikely be wanting more.

-David
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Old 11th March 2007, 06:24 PM   #3
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Quote:
Originally posted by dw8083
Richard Vandersteen states that bi-wiring provides most of the benefit of bi-amping. Bi-amping according to him is very tricky and not done properly, you will loose the phase coherience/alignment that the speakers are famous for producing. He expressly states that you MUST use the exact same amps when you are bi-amping.

I have a pair of Vandersteen 2ce's driven by an Aleph30 in a bi-wired configuration, and the sound is simply astonishing. Friends and neighbors who come over and listen are dumb struck by the sound; the hugh sound stage, the imaging, and how authorative and musical the system is to listen.

Just use your Aleph 3, bi-wire it and enjoy! The 2ce's have a nominal impeedence of about 6 ohms. The aleph 3 will drive them louder than you will care to listen to at high levels. Plenty of power, and you will very unlikely be wanting more.

-David

WOW.. thanks very much for responding.. never dreamed I'd find someone with the same speakers and a similar amp here!

Yes, I had planned to try it all by its lonesome.. I was anticipating a lack of bass (I am a bit of a rocker.. wait, no, I rock). I thought if that did occur as many have witnessed the amp of choice for the low end would be the 400a.. I also thought it would be rather cool to use Nelson Pass's old design with a new design.

As much as I love Richards products as is the case with all engineers he goes a but off the deep end with comments like that.. in my opinion.. I think if one likes the sound one can do what ever he/she pleases assuming it does not cause a failure as I am fearing based on his comments.. thats why I started this thread.. I'm not sayng he is wrong, I am just saying it is possible to run 2 different amps and achieve results personally pleasing. ESPECIALLY with 2 class A amps by the same designer.

I'm curious.. this is a hobby of always wanting more.. never satisfied.. have you not had the urge to upgrade to his signature 2ce's? Or even now his 2ce sig II's?

I have, but what has stopped me is reading comments from users complaining of the same issues with the signatures as I have with the 2ce standards.. A veiled sound with lack of air. I am hopefull that the Aleph 3 is going to fulfill my craving in these two area's and your comment further qualifies that it may very well.


thanks!

Joe
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Old 11th March 2007, 07:21 PM   #4
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Default Re: Old meets new but can this be solved?

Quote:
Originally posted by barchetta
MY question..

Is there a way around this? I know the Aleph 3 is known to be an incredible stable amplifier.. Might it be safe to run bi-amped with these two exceptional class A amplifiers?

Does the Aleph 3 self bias? Would I need to monitor the bias of the 400a?
The Aleph 3 self biases. If the 400A is properly biased in the
first place, there would be no concern.

I would not expect any instabilities, and I am surprised that
RV has seen any. None of these amplifiers will oscillate into
that load.

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Old 11th March 2007, 07:29 PM   #5
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Default Re: Re: Old meets new but can this be solved?

Quote:
Originally posted by Nelson Pass


The Aleph 3 self biases. If the 400A is properly biased in the
first place, there would be no concern.

I would not expect any instabilities, and I am surprised that
RV has seen any. None of these amplifiers will oscillate into
that load.

OH GOODY GOODY GOODY! I was hoping the creator would respond.. Apogee told me the same thing (Steve).. cool..

Can't wait to experiment..

I bet you the occurances of this is rare and he really doesn't want to feel responsible for any failures so thats why he errors on the side of caution.. I would do the same thing if I were him.. there are some pretty expensive amps out there to wreck.


Also; in response to the previous post; I believe one of the design objectives of the Aleph 30 in response to feedback on the Aleph 3 were increased bass response.. I think I read that.. This is why I think this might be a PERFECT match.. Old meets new!
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