SR-009 vs Orpheus/SR-Omega/O2s? - Page 13

May I ask you guys what a 3 year old SR007 MkII + SRM 727II combo in really good condition is worth these days?

Might be able to get a deal on them.

Would be the price in Europe, I think that might differ a bit from the US.

I wouldn't go over 3k

Sorry, I edited the post for price in Europe.

that would be 2300€ then I suppose?

Yup, though I don't know much about the market differences for Stax products in Europe.

I think a set like this is over 5k€ new here. (catalog price)

Don't take my word for it though.

Might have been over 5k$ converted to Euro.

Anyway, maybe interesting for Europeans who want an O2Mk2 and 727II at 2000€. Link.

Not bad, that's almost exactly what I paid for an O2MK1/727II package two years ago.

Quote:

Originally Posted by spritzer 

 

 

I'm also working on a SET 300B amp to drive electrostatics but this would be a much better fit IMO for the HE90's than any Stax.  The 300B's are limited in voltage and power so the only way to get acceptable low distortion power levels is to use a higher ratio transformer but that is always a loose-loose situation.  I'm going to finish my DIY HE90's in the new year so I'll be able to compare it directly. 

I'm curious about your 300B design. The problem, as you mention is an appropriate output transformer. The custom single-ended Electra-Print transformers I  own have a 1:2 step-up with a 3K primary. According to Jack Elliano, this was about the  maximum feasible  step-up ratio possible without either reducing the primary impedance or sacrificing bandwidth.  This works fine with an EL34 or 6550, and the 3K load is standard for a 300B. The big problem is the low mu of the 300B. A 1:2 step up  with a 300B doesn't provide enough voltage gain or swing to really drive electrostatic headphones.

Quote:

Originally Posted by msjjr 

I don't know if this is relevant to your point, and I must add I a not an engineer, but the Stax is easier to drive than the HE-90's with my amp, ie louder sooner. The hybrid 300 B's and the HE-90's are audio heaven for me.

I'm not an engineer either but that's no excuse...   It's strange that the Stax would be more sensitive on your amp since the HE90 is far more sensitive with everything being setup properly.  Something must be very wrong with the headphone bias to get that effect.  

Quote:

Originally Posted by FrankCooter 

I'm curious about your 300B design. The problem, as you mention is an appropriate output transformer. The custom single-ended Electra-Print transformers I  own have a 1:2 step-up with a 3K primary. According to Jack Elliano, this was about the  maximum feasible  step-up ratio possible without either reducing the primary impedance or sacrificing bandwidth.  This works fine with an EL34 or 6550, and the 3K load is standard for a 300B. The big problem is the low mu of the 300B. A 1:2 step up  with a 300B doesn't provide enough voltage gain or swing to really drive electrostatic headphones.

 

I'm going to start off with the Ciuffoli design pretty much stock (except the bias supply since I'm not a fan of burning up my diaphragm coatings) and see how it works.  1:2 really isn't enough and the Ciuffoli amp isn't that much better at 1:2.25 but the Lundahl iron is cheap enough to play with.  What I really should be doing is building KG's insane all DHT, fully balanced 3 stage beast (so 12 DHT's in a single amp, AD-1's, 300B's and 845's) but I don't really feel like dropping 6k$ on just the parts.... 

Now I'm going back to figuring out how I'm going to build the smallest, self contained Stax amp I can.  Think Egmont in a SRD-7 box... 

I don't hear anything above 12 or 13K, and I have more severe HF hearing loss in one ear. The brightness I'm hearing is probably in the presence range.
 

Quote:

Originally Posted by Anders 

spritzer, is there any possibility to modify the BHSE to get better synergy with the SR-009? I am very satisfied with BHSE/O2 so it is more a theoretical question, or for future relapse into upgraditis. With regard to present information, I would not buy the SR-009 without listening first. In a long perspective, it seems to be a good option for compensating for hearing loss due to age.