Jim Gregory Posted July 25, 2019 Share Posted July 25, 2019 I use a First Watt SIT3 “11.5 dB gain” for the HF (Klipsch K402 w 3” Radian 760 drivers) and a pair of Pass Labs Aleph 2 “20 dB gain” for the LF (Klipsch 904 w k45k drivers) Use Marchand XM44-4 for crossovers. Path is Auralic Vega G2 … Marchand… HF SIT3 … LF Aleph 2. Called Mark at Renohifi and at his suggestion contacted Kent English at Pass Labs. Kent suggested I try Harrison Labs RCA signal path attenuators “metal film resistors”. Put a pair of -3dB at connection to SIT3 and -12dB at connection to Aleph 2. (they do not make -9dB attenuators otherwise I could have installed one pair to Aleph 2). It works really well but would like to use balanced connections to the Aleph 2. Any suggestions or other reasonable alternatives to gain balance the amps is greatly appreciated. Quote Link to comment Share on other sites More sharing options...
joessportster Posted July 25, 2019 Share Posted July 25, 2019 4 hours ago, Jim Gregory said: I use a First Watt SIT3 “11.5 dB gain” for the HF (Klipsch K402 w 3” Radian 760 drivers) and a pair of Pass Labs Aleph 2 “20 dB gain” for the LF (Klipsch 904 w k45k drivers) Use Marchand XM44-4 for crossovers. Path is Auralic Vega G2 … Marchand… HF SIT3 … LF Aleph 2. Called Mark at Renohifi and at his suggestion contacted Kent English at Pass Labs. Kent suggested I try Harrison Labs RCA signal path attenuators “metal film resistors”. Put a pair of -3dB at connection to SIT3 and -12dB at connection to Aleph 2. (they do not make -9dB attenuators otherwise I could have installed one pair to Aleph 2). It works really well but would like to use balanced connections to the Aleph 2. Any suggestions or other reasonable alternatives to gain balance the amps is greatly appreciated. Why not use the attenuate'r on the Marchand ? I have used Marchand for YEARS and never had an issue where the amps could not be balanced. (Of course I always use amps with gain controls) I also use my ears to determine balanced sound Quote Link to comment Share on other sites More sharing options...
Jim Gregory Posted July 25, 2019 Author Share Posted July 25, 2019 The amps I used before also had adjustable gain controls. The Marchand has 12 position stepped attenuators @ 1 dB steps. I understood this to be for leveling volume. Have I misunderstood and this is control is for adjusting gain to the amplifier ? Quote Link to comment Share on other sites More sharing options...
babadono Posted July 25, 2019 Share Posted July 25, 2019 You can make your own balanced attenuators. @Marvel sent me a link to an online calculator. I'll see if I can find it. Or perhaps he will kindly link it again. Quote Link to comment Share on other sites More sharing options...
Jim Gregory Posted July 25, 2019 Author Share Posted July 25, 2019 3 minutes ago, babadono said: You can make your own balanced attenuators. @Marvel sent me a link to an online calculator. I'll see if I can find it. Or perhaps he will kindly link it again. Appreciate the help. Quote Link to comment Share on other sites More sharing options...
Khornukopia Posted July 25, 2019 Share Posted July 25, 2019 1 hour ago, Jim Gregory said: The Marchand has 12 position stepped attenuators @ 1 dB steps. It looks like you should be able to set your gains with those controls. Quote Link to comment Share on other sites More sharing options...
Marvel Posted July 25, 2019 Share Posted July 25, 2019 @Jim Gregory I just sent it to you in a PM. Quote Link to comment Share on other sites More sharing options...
Jim Gregory Posted July 25, 2019 Author Share Posted July 25, 2019 13 minutes ago, Khornukopia said: It looks like you should be able to set your gains with those controls Thank You Sir. I will try that. Quote Link to comment Share on other sites More sharing options...
glens Posted July 25, 2019 Share Posted July 25, 2019 It appears the level controls are +/- 6 dB with unity gain at the midpoint according to their website. If you need more separation than that I guess you could insert a resistor in series with the level controls which need even more attenuation. What steps are you taking to shape the signal going to the 402s so they achieve a flattened response (as constant directivity horns require)? Quote Link to comment Share on other sites More sharing options...
babadono Posted July 25, 2019 Share Posted July 25, 2019 1 hour ago, Marvel said: @Jim Gregory I just sent it to you in a PM. Duh yep you sent it to me also in a PM. Thanks again Marvel. 1 Quote Link to comment Share on other sites More sharing options...
MenloBob Posted July 25, 2019 Share Posted July 25, 2019 I use one of these to attenuate the signal for the amplifier channels driving my K510s. It is very transparent, using a very nice ALPS 27 pot. Has both balanced and unbalanced connections. https://www.amazon.com/gp/product/B01MXC9HHW/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1 1 Quote Link to comment Share on other sites More sharing options...
guf Posted July 25, 2019 Share Posted July 25, 2019 just an observation... are we using gain and volume as if they are the same thing? Quote Link to comment Share on other sites More sharing options...
babadono Posted July 25, 2019 Share Posted July 25, 2019 12 minutes ago, guf said: just an observation... are we using gain and volume as if they are the same thing? Good point yea I don't know. Maybe even step back further, did it sound wrong without any attenuation? Because all of this is just playing around without a calibrated measurement mic and REW or similar. What I can say is thank God and human engineering for 24 bit 96kHz active digital crossovers 2 Quote Link to comment Share on other sites More sharing options...
guf Posted July 25, 2019 Share Posted July 25, 2019 2 minutes ago, babadono said: Good point yea I don't know. Maybe even step back further, did it sound wrong without any attenuation? Because all of this is just playing around without a calibrated measurement mic and REW or similar. What I can say is thank God and human engineering for 24 bit 96kHz active digital crossovers i never could get that figured out. Quote Link to comment Share on other sites More sharing options...
Khornukopia Posted July 25, 2019 Share Posted July 25, 2019 38 minutes ago, guf said: just an observation... are we using gain and volume as if they are the same thing? 16 minutes ago, babadono said: Good point yea I don't know. Maybe even step back further, … 13 hours ago, Jim Gregory said: I use a First Watt SIT3 “11.5 dB gain” for the HF (Klipsch K402 w 3” Radian 760 drivers) and a pair of Pass Labs Aleph 2 “20 dB gain” for the LF (Klipsch 904 w k45k drivers) After stepping way back, I am curious about what these "gain" specs reference. Quote Link to comment Share on other sites More sharing options...
babadono Posted July 25, 2019 Share Posted July 25, 2019 1 hour ago, Khornukopia said: After stepping way back, I am curious about what these "gain" specs reference. I think he is referring to the nominal gain of the First Watt amps themselves? Quote Link to comment Share on other sites More sharing options...
glens Posted July 25, 2019 Share Posted July 25, 2019 That'd be total gain from input to output. Quote Link to comment Share on other sites More sharing options...
glens Posted July 25, 2019 Share Posted July 25, 2019 I'd like to hear how the response-shaping for the 402s is getting done in this setup. My guess is that without it things won't sound right. Quote Link to comment Share on other sites More sharing options...
Jim Gregory Posted July 25, 2019 Author Share Posted July 25, 2019 3 hours ago, glens said: It appears the level controls are +/- 6 dB with unity gain at the midpoint according to their website. If you need more separation than that I guess you could insert a resistor in series with the level controls which need even more attenuation. What steps are you taking to shape the signal going to the 402s so they achieve a flattened response (as constant directivity horns require)? Just trying to gain match the amplifiers right now, later will attempt some EQing. Quote Link to comment Share on other sites More sharing options...
Jim Gregory Posted July 25, 2019 Author Share Posted July 25, 2019 3 hours ago, MenloBob said: I use one of these to attenuate the signal for the amplifier channels driving my K510s. It is very transparent, using a very nice ALPS 27 pot. Has both balanced and unbalanced connections. Thank You. I will take a look at this as well. Quote Link to comment Share on other sites More sharing options...
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