[dewar]

The SSI crossed over at 380hz, surely not?

I've got one of the Bottlehead SEX amps on the way so we'll see how 2 watts gos with the SSI's. But I suspect I might use it as a pre before a Red Wine amp. Those unused speaker taps might be put to use driving some rear Radian tweeters perhaps?

Will we ever see published graphs of the SSI? Would help us tweekers.

cheers
B.

[hurdy_gurdyman]

The SSI crossed over at 380hz, surely not?

I've got one of the Bottlehead SEX amps on the way so we'll see how 2 watts gos with the SSI's. But I suspect I might use it as a pre before a Red Wine amp. Those unused speaker taps might be put to use driving some rear Radian tweeters perhaps?

Will we ever see published graphs of the SSI? Would help us tweekers.

cheers
B.

The SSI has a low pass inductor at around 380 Hz. The high pass is much higher. The two meet in the middle at around 2 kHz. The response is very flat. It works. One must design the XO around the drivers used, not a XO crossover calculator. Few drivers have a ruler flat response, so few will end up using what a calculator calls for. This is the "artistic" part of XO/speaker design mixed with the science.

As for graphs, I don't know. Not my call.

Dave

[dewar]

Makes sense, thanks.

 

[hurdy_gurdyman]

On graphs, I know there are factory Eminence graphs on the Hawthorne Audio website. I don't remember where, and not sure if the 15 Sterling Silver Iris Coaxial driver has had its graph posted or not. Send Darrel a note and ask him. He's good about answering, although it may take a day or so. The Radian 475 has a graph posted on their site. I don't have the link info on hand, but shouldn't be hard to find. Anyone considering doing their own XO should be able to do OK with the two driver graphs. If you can't find the SSI graph, the PSI is similar enough to get you in the ballpark for a good starting point.

I think a rear Radian driver in a proper horn should work great on the back of the OB. I haven't been able to afford this, and not sure if it's worth it in my baffle's location. In some rooms it could be very worthwhile. I believe Darrel sells the tweeters separately for the DIY folks.

I really shouldn't be talking so much about the SI line here, as it could be taken as promotion. I was just keeping it to OB's in general and just some general SI posts that were here. I wasn't planning on getting into so much SI talk. My apologies to the moderators if I'm pushing the rules a bit here.

Dave

[Dmason]

Bottlehead SEX amp is impressive; a very refined and evolved circuit pored over by many people who know their oats.. parafeed makes for a VERY chunky 2 watts, and the voltage side of the 6DN7 has ALOT of jam, the circuit and tube choice are perfect. It is an amazing little tube, part 6SL7, and a 2A3 on the big side.. no mushy bass there, a very clean, and linear sound.

I have strapped mine over to use the voltage driver as a pre amp and it is suddenly a super high value pre amp. Extremely low noise floor, and ... I have tried that as a pre amp to my Red Wine Signature 30. Tube slam, into a batTery amp. A+ combo, ultra high value. Dave and Darrell's ideas would fit perfectly.

[dewar]

Apologies for getting off topic,

but can I ask you quickly Dan, or anyone, what "strapped over to use the voltage driver" means. I've got zero DIY electronics experience and was simply going to use the headphone out, but if there is a better way could you possibly point me in the right direction?

Thanks
Bevan

got 7' behind my speakers so pretty confident I can get a rear tweeter to work. affording it is my problem too.

[gooberdude]

You might try and push your speakers a bit closer to the wall if you can.

There is large area behind my speakers as well & the performance is a heck of a lot better 5' from the wall as compared to 7'.   

there is an optimal distance to the wall to achieve a 4.6 ms delay - but don't quote me!   i read that somewhere, maybe hawthorne's website or forum.

the bass gets stronger as you get closer to the wall...then find a compromise for imaging.

not side walls!    the wall behind the speaks.