This again?! Powered speakers with Crack.

Kitchener · 1503

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Offline Kitchener

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on: January 21, 2018, 10:56:41 PM
So, I'm sorry for doing this.
I know, I know, I've seen all the posts about "what speakers can the Crack power" and I've read all the replies stating in no unclear terms "NO, FOR CRYING OUT LOUD, GET THE S.E.X. MAN!".

But, and I must state up front that I know exactly two things about audio and amplification: jack and shit.
But what about "powered" speakers like the JBL LSR305 studio monitors?

As I understand, hah, these speakers have built in amplification and can be connected directly to a PC-soundcard/DAC and require no external amplification.

And I've tried, really tried, to make sense of the specs sheet (included below, for ) for the speakers compared to what I know of the Crack ("output impedance 120 ohms, gain about 15dB into a 300 ohm load like a Sennheiser HD600, max output about 10V into a 300 ohm load" and output wattage of about 1/3 Watts)
But it is impossible for me as a complete layman to draw any sort of conclusion from this information.

I'm sure this must be a tiring subject, but would the Crack be able to squeeze sweet tube harmonics out of powered speakers?

Sorry.

Modded, Speedballed Crack + Sennheiser HD6XX
STAX SRM-353X + SR-L500
STAX SRM-313 + SR-L300
-Jørgen E. J.


Offline Paul Birkeland

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Reply #1 on: January 22, 2018, 06:03:58 AM
Those speakers can take a maximum of 10V of input signal, though I'd imagine that there's an input trim control that would have to be way, way down for that to work out.

You can make a 1/4" TRS to stereo XLR cable to hook these up.  You could also get a pair of 600:600 output transformers and run XLRs from the Crack to those speakers with XLR cables. 

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Kitchener

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Reply #2 on: January 23, 2018, 02:41:37 AM
I've included an image of the controls of said speakers, so I'm guessing they need to be at +4dBu?

Cables shouldn't be an insurmountable challenge I think.

Frankly this is all academic, but it would be neat to know that there are at least options down the line for a small desk setup.

Modded, Speedballed Crack + Sennheiser HD6XX
STAX SRM-353X + SR-L500
STAX SRM-313 + SR-L300
-Jørgen E. J.


Offline Paul Birkeland

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Reply #3 on: January 23, 2018, 03:51:52 AM
The input sensitivity switch would potentially be helpful to give a bit more flexibility.  I doubt they need much more than 1V of signal to meet your needs (2.2dBu).

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline 2wo

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Reply #4 on: January 23, 2018, 10:49:27 AM
Looks like they can use a 1/4 unbalanced connection as well...John

John S.