[oris98]

Hi all,

Are the marble 9 speakers easy loading for tube amp ?  Based on their spec, 85 dB efficiency, it takes at least 60W - 80W to drive.  It is not too easy to find good sounding tube amps at this power leveL for budget price like Norh.  Some people said if the speakers are easy with loading, it can be drived with lower power amp...  

What is the loading spec for the Norh 9 ?  Many thanks.

[Marbles]

The 9.0's are 8 ohm nominal impedence and 86 db 1m/1Watt.

Because of the design of the rear port, there is almost no back pressure like in a traditional box speaker.

This lets the 9.0 be driven by less powerfull amps.

I would not run them on less than 30 watts, but many can and be happy.  Much would depend on the size of your room, how loud you like your music and the type of music you listen to.

[oris98]

Hi Marble,

My room is 17x17 and 80 % of time I play Jazz, 10% light rocks such as Jennifer Warnner, etc. I also use my norh 9 for watching movie with a power sub (movie only not musical).  

Any suggestions on tube amp to match with the Norh 9 ?   I am using a Bryston 3BST it drive it. After assembled the new XO (Dennis Murrphy's design) with seperate binding posts for tweeter and woofer.  I want to do Biamping with passive xo.  If I keep my Bryston for the woofer, what is a good choice of amp for driving the tweeter ? Norh SE9 ?  o ASL ? Dared VP20 ?   If I decided to move to a single tube amp to improve on the 3D imaging what is the good choice ?  Someone suggest the Jolida 302B (50WPC PP) ?  Any other suggestion ?

[oris98]

Hi Marble,

My room is 17x17 and 80 % of time I play Jazz, 10% light rocks such as Jennifer Warnner, etc. I also use my norh 9 for watching movie with a power sub (movie only not musical).  

Any suggestions on tube amp to match with the Norh 9 ?   I am using a Bryston 3BST it drive it. After assembled the new XO (Dennis Murrphy's design) with seperate binding posts for tweeter and woofer.  I want to do Biamping with passive xo.  If I keep my Bryston for the woofer, what is a good choice of amp for driving the tweeter ? Norh SE9 ?  o ASL ? Dared VP20 ?   If I decided to move to a single tube amp to improve on the 3D imaging what is the good choice ?  Someone suggest the Jolida 302B (50WPC PP) ?  Any other suggestion ?

Many thanks in advance..

[Jay S]

oris98,

Many people have biamped the nOrh 9 using a simple tube amp like the ASL Wave 8 9 watt/channel monoblock tube P-P amp for the tweeter and a SS amp (such as your Bryston) for the woofer.  The Wave 8 seems to respond well to simple tweaks, e.g. a strategically placed Auricap -- I think www.diycable.com has info on that.  

As for using a single tube amp to power both woofer and tweeter, I think 8 watts/channels is ok for normal listening provided your room isn't too big and you don't crave big dynamics.  I was powering my Avinci 1 bookshelf speakers (like the nOrh 9, uses the Scanspeak Revelator woofer and has a rear port) with my 8 watt/channel Radii Audio 300B SET tube amp and it produced pretty good volume levels in my bedroom.  That said, I would not have been happy with that combo in my living room since a) my living room is more than double the size, and b) I want to be able to crank it up loud and enjoy powerful dynamics (hence the 250 watt/channel digital amp in the living room).  I have also auditioned the Avinci with a 30 wpc P-P tube integrated amp (an ASL AQ1003, cost <$1k) and it produced good volume and dynamics, enough to I think be happy with.  What is great about tubes is that you can tube roll (though perhaps the cheaper way to do this is through your tube pre).  

Do let us know how you like your Dennis Murphy XO.  I've been meaning to get it built for my 9.0s as well but right now my priority is getting a better transport / modded universal player.

[oris98]

Hi Jays,

Thanks for your reply and comments.  Does you Marble 9 gives you good 3D holographic imaging ?   Do you like the imaging, base response and dynamics with the 30WPC ASL 1003 amp ?  Do you know who has the Wave8 for driving the tweater?  From the link you provided, there isn't any connection to the Auricap mod for Wave 8.   Can you please reconfirm with the URL ?  Do most of the people like this combination?
Many thanks in advance..


The xo from Dennis Murphy is definitely providing significant improvement to the 9s..  Much fuller mid range and more transparent and tigher base. It adds more depth to the overall imaging.  Before the upgrade, the 9s sound faqtique and after upgraded the xo, music is much more musical and smoother..  All the benifit for the cost of $75 - $150 dependend on the parts it uses.  Best bang for the $ upgarde  IMO.  
In additional, it allows me to bi-wiring or bi-amping the 9s.

[oris98]

Hi Jays,

Thanks for your reply and comments.  Does you Marble 9 gives you good 3D holographic imaging ?   Do you like the imaging, base response and dynamics with the 30WPC ASL 1003 amp ?  Do you know who has the Wave8 for driving the tweater?  From the link you provided, there isn't any connection to the Auricap mod for Wave 8.   Can you please reconfirm with the URL ?  Do most of the people like this combination?
Many thanks in advance..


The xo from Dennis Murphy is definitely providing significant improvement to the 9s..  Much fuller mid range and more transparent and tigher base. It adds more depth to the overall imaging.  Before the upgrade, the 9s sound faqtique and after upgraded the xo, music is much more musical and smoother..  All the benifit for the cost of $75 - $150 dependend on the parts it uses.  Best bang for the $ upgarde  IMO.  
In additional, it allows me to bi-wiring or bi-amping the 9s.

[ohenry]

Wave 8 mods:  Most people simply replace the 0.47uF 450V Bennic caps with Auricaps of the same value. It does make a cost effective sonic improvement and it's a simple procedure.

Edit:  Here's a link for you.  http://www.geocities.com/asl_wave8/modsum.html

And another for resister replacement. . .
http://www.audioasylum.com/audio/tubes/messages/60782.html

The Bennics were actually 0.22uF and replaced with 0.47uF.  Sorry about the mix up.  I did that 6 months ago and have little recollection.  

[oris98]

If I use wave 8 to drive the tweeter, will the gain match ok with my Bryston 3BST ?  I tried to biamp the 9s with IRD MB100 to drive the tweeter and my Byston for the woofer.. It sound pretty good.  However,  it may be wasteful to use a 100w MB100 to drive just the tweeter..  The gain for IRD and Bryston seems working ok together without a seperate gain control.

Can anyone share their experience biamping Marble 9 with wave 8 or other tube amp ?

Thanks in advance..

[Jay S]

Oris,

Sorry for not replying sooner - I had lost track of this thread.  

My marble 9s are good in terms of lateral and vertical imaging.  In termss of depth, I do get a sense of depth and layering but my speakers are hindered by the fact that they are quite close to the back wall -- by necessity since my room is not very deep (though it is quite wide).  Some recordings are of course better than others but by no means is the soundstage flat.  

Glad to hear that the Dennis Murphy XO makes such a noticeable improvement in so many different aspects. As far as the highs, I don't doubt the new XO helps.  In my set up, I've gotten very pleasing and refined highs but at a cost of using rather expensive components -- switching to a cheap dvd player as a transport really was a noticeable step backward.  Some components that had more HF energy than my old reference setup could be more detailed but also less enjoyable in the long term.  So, I would guess that the stock XO/parts are not too forgiving.

I will get around to replacing the XO.  Did you have trouble removing and reinstalling the old XO?  I may go with an external XO, though that will be more costly.

[oris98]

Hi Jay,

I have the new XO mounted externally.  I disabled the internal XO and uses its silver braid wire inside to connect directly to the driver from the binding post.  I then use the same silver braid ( I have extra long wire inside) connecting to the output binding posts in the external XO box.  A reasonable looking project box housing the XO inside.  This XO box mounted directly underneath the top plate of the speaker stand to minimize the length of the wire.  It works good.   The new XO has the tweeter and woofer splitted to aim for biamping in the future (waiting for the IRD PT2 or Audiophile).  In the mean time, I just biwiring the 9s.  

Are you still living in HK ?  I am planning a trip to HK and China in October, do you think we can meet up and talk  ?  and you may show me your setup ?  

I just a acquire a pair of ASL AQ1006 mono block with 845 tube.  Wow, it gives the same kind of snappy base as my Bryston 3BST.   I can see why people go for tube amps as it sound a lot smoother..

[Jay S]

Hi, thanks  for the reply.  Its been recommended to me that I mount the XO externally too.  My two priority projects have to be upgrading the XO as well as getting a decent transport (somehow my plans to get a modded universal player aren't quite coming together).  

I should be in HK in Oct.  Do let me know in advance when you are around so I can update you on my travel plans.  I'd be happy to meet up and give you a listen.  That said, I would have to buy/borrow a good transport by then as my system has come down several notches since I fell-back to using my 4+ year old  dvd player as a transport.

Regards,

- Jay

[oris98]

Hi Jay,

Thats great !  In fact, I am also using a fairly old Cal. Lab Icon MKII as transport and using the Mensa DIO.  I should be in HK in between 16 - 20.  For the room acoustic issue, me too, I have to set up my 9s closer to the back wall in the wider but short room dur to WAF.  Tonight, I just moved them futher out and closer to me, it has much better dynamic and imaging with my new ASL 22WPC SET AMP.

I will update you when time get closer and looking forward to listen to your setup there..

Thanks again..

[Jay S]

I should be in HK in mid/late Oct.  Let's get in touch again as your trip draws nearer.