Powered Subs


#1

I recently bought a Directstream DAC w/bridgeII and the manual says to use a Y RCA cable if I want to send another full signal to powered subs. The XLR and RCA are connected on the DS and using both at the same time could create a problem. For my 3.6 Maggies I use a high pass filter at 50hz. The M700’s do not have RCA inputs. How do I send a balanced out to my OB GR Research Rythmic powered subs? There are some 1X4 XLR boxes that route the same signals. For the high pass filter, I guess a balanced crossover box is needed. I can see that the XLR world gets more expensive.


#2

Oneartist - though I have the Jr. rather than the Sr., which does not list the recommendation in the manual against using both outputs at the same time, if I recall correctly (owners and/or Paul, check me here) that line was put in the original Sr. manual simply to avoid less knowledgeable owners running into issues with level differences and wiring differences - and not to suggest that you can’t or should not use both.

EDIT: I asked Paul, and he says:

“Senior has an output transformer that really likes to be evenly loaded, thus we don’t recommend using both DS outputs. JR has a solid state output and doesn’t care about uneven loading.”


#3

I use a Mogami XLR “Y” cable to split the output of my DS between my M60 amps and the SUB225 bass modules of my Avantgarde Duo Omegas.

I have a GNS PASI isolation transformer on the side of the “Y” that connects to the SUB225s.

That prevents having the inputs of my M60s connected to the inputs of the SUB225s.

MSB sells a “sub isolator” for the output of their DACs to connect subs, they are a bit pricey.

There is also Marchand Electronics, Phil can fix you up with a DIY or fully assembled crossover in just about any flavor that you could desire, active or passive. When I had 3.6s, I had a Marchand tube crossover to actively bi-amp them. ( XM126 )

If you do not want to go active crossover, you could just go with a “Y” cable > Marchand passive low pass in line XLR .

If you want some isolation, just search XLR isolation, there are quite a few pro audio solutions. ( Phil may even be able to incorporate that feature for you )

I try to avoid inserting anything in line between the M60s and my DS, the Mogami “Y” is very transparent.

Pruist Audio Design also markets very well made “Y” adapters, once again a bit pricey, when the Mogami “Y” XLR will do the job just fine.

ADD EDIT:

Do your subs have speaker level inputs? That could be an option for you. I have that option also, but it does not permit me to incorporate any form of bass correction, which my SUB225s lack. That is why I run the XLR “Y” adapter.


#4

According to the Stellar M700 rear panel picture, it does have both a balanced XLR and an RCA input connector.

http://www.psaudio.com/products/stellar-m700-power-amplifier/#tab-rear-panel

The In and Out markings are for the 12 volt trigger that can be used to turn the amp on and off.


#5
MrDerrick said

I use a Mogami XLR “Y” cable to split the output . . .

That is a lot of valuable information. Thank you.

#6
Bill Stanwick said

According to the Stellar M700 rear panel picture, it does have both a balanced XLR and an RCA input connector.

http://www.psaudio.com/products/stellar-m700-power-amplifier/#tab-rear-panel

The In and Out markings are for the 12 volt trigger that can be used to turn the amp on and off.


I think you are right. I just got them yesterday and the Trigger out next to the RCA confused me. Thanks for the heads up.

#7

I have a bad habit of getting something new and thinking I can first just look at it to figure out how it works. My first quick look over of the M700’s was pretty bad. After I read through the manual I see that much of what I said above was wrong.

I am having trouble switching from stereo DS to surround Oppo 205. I have two metal 2X1 switch boxes. 205’s stereo XLR DAC L&R goes to input 1 L&R in of the first box and 205’s stereo RCA goes to input 1 L&R of the second box. When I push the 1 button on both boxes the XLR is routed to the 3.6 speakers from the first box and the RCA stereo is routed to the OB subs from the second box. This works as expected.

The RCA outs of the DS DAC are Y split. One L&R goes to input 2 L&R of the first box and the other L&R goes to input 2 of the second box, which routes to the OB subs. When I push both 2 buttons, nothing. No sound from the speakers. I am going to try some elimination test. First, I plan to switch the inputs in the first box. There is an optical and a Coax out cable from the 205 to the digital in’s of DS. Maybe something is wrong with the connections. The vol shows up on the DS screen but no sound.

The amps are sounding better and better the longer I play them.