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Shahinian Obelisk Upgrade

L

lebo

Member
I have a set of circa 2004 Mk-1 Shahinian Obelisks which I adore aside from the weak/muddy midrange sometimes experienced from studio recorded non-classical music. This weakness is often noted in reviews/forums.

Has any owner out there done the Obelisk crossover/woofer upgrade ( http://shahinianacoustics.com/ServiceInformation.htm )?

Any comment on the value/difference it makes?

Will that bring my Mk-1's close to the Mk-2 or is a Mk-2 still significantly different?

Does the upgrade and/or Mk-2 address the sometime muddy / weak midrange? Or as someone who listens to more non-classical than classical, would trading in on the Arc-2 be a better option?

Any thoughts?

Thanks,
 
I'd be interested in knowing what the upgrades do as well.

However, I am surprised you find the midrange weak. The presentation is different from traditional box speakers, especially monitor types - so the soundstage is more diffused. Is this what you mean by muddy mid range?
What amps are you using by the way? I found powerful amps not only tighten the bass but improved the clarity of the mids as well
 
By muddy, I mean some vocals just seem lacking presence in the mid-range. A few friends who've heard them say the same. Perhaps the room?

I seem to recall there was a forum comment that suggested the mk-2 's new bass driver and changed crossover frequency address the issue. Also noted was the early Arc's didn't have the same issue.

Interconnects are Kimber silver (upgrade from cheaper Kimber helped the top end) and speaker cables are Kimber (upgrade helped the tightness of the bass). Amp is Perreaux 200i. I do wonder if the amp is slightly underpowered, although it is a high current delivery, low output impedance amp......
 
lebo said:
By muddy, I mean some vocals just seem lacking presence in the mid-range. A few friends who've heard them say the same. Perhaps the room?

I seem to recall there was a forum comment that suggested the mk-2 's new bass driver and changed crossover frequency address the issue. Also noted was the early Arc's didn't have the same issue.

Interconnects are Kimber silver (upgrade from cheaper Kimber helped the top end) and speaker cables are Kimber (upgrade helped the tightness of the bass). Amp is Perreaux 200i. I do wonder if the amp is slightly underpowered, although it is a high current delivery, low output impedance amp......
Click to expand...

The Perreaux should be a good match (I use a Hegel H360). I dont feel mid range issues in my room but can have slightly toppy treble at times, but I've learned to live with iy.
I can imagine how a change in crossover may address that and also your mid range, but it seems like the crossover can be used only with the new woofers - so both upgrades are required.

Strongly recommend contacting John Burns at Pear Audio with your questions - he is a long term Shahinian distributor and incredibly helpful and knowledgeable.
On a more selfish note, would love to hear what you find out please - I am not considering an upgrade to my Obelisk Mk 1s at the moment but might be a future consideration
 
Mk1 Obs are notoriously fussy. I'd say upgrade your amp to something like Dynavectors or one of the better pre-powers with more grunt / ability to kick out loads of current at low impedance. I suspect you are only scratching the surface of your speakers potential.
 
I should add that if you can hear other amps I'd try to do that then you will know the answer re your amp. Or take your amp round to an Obelisk owners.

I've listened to Obs with Dynavectors, Plinias, Passlabs, Avondale and Meridian - the Dynavectors get my vote as the best I've heard.
 
I owned a set of early 2000 obs mk1's and did consider trying to upgrade them similarly to yourself. In the end I kept my eye out for a used pair of obs mk2 and haven't looked back. The mk1 obs are fine speakers and need lots of current to get the best from them... Plinus, dynavector, meridian & of course Vitus which Is what I am using with my mk2's.

Mk2's just do everything that bit better so my advice would be to look out for a used pair and trade/sell your mk1's to part fund. Id have offered you a demo of my mk2's but I see your based in New Zealand so that's out of the question.
 
I would think Shahinian themselves would have all the insight needed regarding the OP. Vasken Shahinian has always been very helpful and responsive to my queries.

Their (admittedly static) website does have this to say:

After a woofer and crossover mod, the old Obelisk is 95% of the current Obelisk
Click to expand...

I assume by "current" they mean a late model Mk I rather than a Mk II. So that leaves an upgraded early Mk I 5% short of a late model Mk I, plus whatever the difference is between late Mk I and a Mk II.
 
Thanks for the advice guys; especially amps and I need to take a look at this. I suspected an upgrade might be required. Perhaps a first step as the i200 is getting a bit tired.

The Shaninians are scarce as hens teeth to get here, but there's a set of Arc-2's new available from the importer atm.

Which is where I'm conflicted. Back when I got the Ob's the sentiment was the Arc was the 'rock' speaker and the Ob's the 'classical' speaker - now the mark-2 versions of both may well have changed all that? I'm more a jazz/rock/50's-70's era guy than classical (albeit I do enjoy some classical and opera).

Or maybe I look for a great s/h amp to drive my OB's really well, and then take out a loan to grab the Arc-2's !! Best of both worlds?

Dunno.
 
I'm considering exactly the same situation... a couple of years back I emailed Shahinian to get a clarification on what exactly the MK2 Obelisk consisted of. I didn't get a clear answer. What I was told is that there is no such thing and that the speakers have evolved over time. I then asked if I could get a list of serial numbers to show where each of the changes happened. Nothing was forthcoming.

I'm on my 2nd set of supposed Mk1 Obs and I was very surprised to find that the 2nd pair image much better and the bass goes lower than the 1st pair.

Knipster, could I please persuade you to gently unscrew the crossover cover on the bottom of one of your speakers and show us all what a Mk2 cross over looks like? I'll do the same with my Mk1s.

My previous Mk1s had the oak veneer and my 2nd pair are cherry - it's just a veneer so I can't believe that's the difference.
 
Dan, seems strange that you did not get much of an answer. While I do not recall the general dates of the MK2, it consisted of new passive radiators and bass unit, both sourced from Seas, along with possible changes to crossover to accommodate new drivers. Also improved cabinet bracing was implemented along with the pyramid/upper part of the speaker supposedly now made of birch ply versus MDF. That is all I know.
 
Obelisks Mark 1 are still a great speaker, especially post 2003. They need an amp that can deliver large amounts of current and they will deliver a thoroughly musical response right across the audio spectrum.
 
I don't play classical music whatsoever but I still love my obs 2's, the problem is as you say they rarely come up on the secondhand market.

A better quality amp will future proof whatever happens with your speaker changes.
 
There is no way, with the right amp, the Ob's suffer with a muddy midrange.
 
Hmm.....ok mixed views on the amp.

In the never ending pursuit of perfection I'd like to fit the upgrade kit - will ring Shahinian. Will let you know if I get anywhere. Not worth paying the cost of freight to send them back to the factory for a refit though. Doubt they'll send me the parts.

On another related question, we moved house short term - the OB's were 4 feet from each side wall, 8 feet from the rear wall, and played into a cathedral pitched ceiling. They 'sung'.

I'm renovating the audio room in our house, and have the opportunity to open up the 9 foot ceiling and create a cathedral space in the ceiling.

Any thoughts? Flat 9 foot ceiling vs. cathedral?
 
If the amp is only 20w then I don't believe it to be powerful enough for the Obelisks which are quite a difficult drive. What is the spec of the amp as information online seems to be variable to say the least: I've seen that it is a 20w per channel amp and a 200w per channel amp!

The best I heard mine was with a Nakamichi PA7 power amp; a 200w per channel Nelson Pass design. This, though lower spec, was comfortably more powerful than a 315w per channel Bryston amp.
 
On paper the power amp looks good at 200W into 8 Ohms and 360W into 4 Ohms. It is also a dual mono design with each amp having its own xformer/power supply.

However a damaged mid-range does (if the source is of high quality) point the finger at the amp. The Obelisk is nominal 6 Ohms but in the treble region hangs around 2 Ohms. This can be a hard load on some amplifier designs. In addition we are dealing with reactive and not purely resistive loads. This means that the phase angle between the voltage and current differs from the 0 degrees for a pure resistor. As the phase angle increases the power into the speaker decreases but the amplifier dissipates more power as heat. At around 45 degrees there is 4 times as much power dissipated as heat as is actually going into the speaker. This is why some amps really struggle.

Another factor is that the ear is most sensitive in this region (many 10,000s times) compared to lower and higher frequencies so any distortion here caused by the difficult load will definitely be heard.

I would suggest to try and get a loan of an amp that is known to drive the Obs like and HX1.2 or HX100 so the OP can hear for himself.

In my case I use two big amps as mono blocks that can deliver >1600Wpc into 4 Ohms and 150A peak into 1 Ohm.

Cheers,

DV
 
oldius said:
If the amp is only 20w then I don't believe it to be powerful enough for the Obelisks which are quite a difficult drive. What is the spec of the amp as information online seems to be variable to say the least: I've seen that it is a 20w per channel amp and a 200w per channel amp!

The best I heard mine was with a Nakamichi PA7 power amp; a 200w per channel Nelson Pass design. This, though lower spec, was comfortably more powerful than a 315w per channel Bryston amp.
Click to expand...

Watts have NOTHING to do with it. It's AMPS that these speakers need and they need them quickly. AshleySimons is sitting on a stack (perhaps literally) of Bedini 25/25's I've tried one with my Obs and they will see off the vast majority of stuff easily. Send him a PM

Failing that buy a JVC AX-1010TN
 
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