Using XLR and RCA inputs with two seperate Pre amps On Odyssey Stratos/Kismet am

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A_shah

Ok,
two questions , I know that the XLR on Odyssey amps are single ended and not balanced just for connivence, So which one should one  use  ?
 what if one is to have two pre amps can one be used with XLR and one with RCA ?

2. What is the preferred way to connect Odyssey amps ? RCA or XLR ?

DaveC113

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XLR just uses pin2 afaik, also there's no switch so I think you can only use one or the other, not both at the same time.

Elizabeth

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It is not a good idea to connect both inputs at amp at same time.
My amp has a switch on the back of the amp to 'select' either the RCA or XLR.. but I would still not connect BOTH at the same time.
One problem is there may be some back emf to the preamp not in use.. which could damage it's electronics.

I use THREE preamps.. But I have one main preamp, and the second and third are plugged into the main one as if any ordinary source. (You can use the tape out, or the volume controlled out from your secondary preamp)

My main preamp is a Bryston BP-26 (with SEVEN METER XLR to the Bryston 4B-SST² amp)
I use a second preamp VAC Standard, as a glorified' tube buffer for digital sources via RCA
And the third preamp, an Audio Research Sp-15 just for the fine tubed phono stage from my Kuzma Stabi Stogi TT via XLR to the Bryston BP-26

I have no problem with daisy chaining the wonderful ARC, and only a small audible loss with the VAC, though the tradeoff in sound is OK for the benefit of tube buffing the digital signal from my old DAC.

A_shah

XLR just uses pin2 afaik, also there's no switch so I think you can only use one or the other, not both at the same time.

thank you ,
But it works ? what I did was use the XLR with the Parasound Halo and the Kismet amp. and the RCA  outputs to the RCA inputs of Kismet from  the Don Sach's 2 pre-amp , I just turn off one unit and the other unit just works fine , vis versa , but I am wondering if their is any harm to it ?

A_shah

It is not a good idea to connect both inputs at amp at same time.
My amp has a switch on the back of the amp to 'select' either the RCA or XLR.. but I would still not connect BOTH at the same time.
One problem is there may be some back emf to the preamp not in use.. which could damage it's electronics.

I use THREE preamps.. But I have one main preamp, and the second and third are plugged into the main one as if any ordinary source. (You can use the tape out, or the volume controlled out from your secondary preamp)

My main preamp is a Bryston BP-26 (with SEVEN METER XLR to the Bryston 4B-SST² amp)
I use a second preamp VAC Standard, as a glorified' tube buffer for digital sources via RCA
And the third preamp, an Audio Research Sp-15 just for the fine tubed phono stage from my Kuzma Stabi Stogi TT via XLR to the Bryston BP-26




I have no problem with daisy chaining the wonderful ARC, and only a small audible loss with the VAC, though the tradeoff in sound is OK for the benefit of tube buffing the digital signal from my old DAC.

Elizabeth,
thank you but that is exactly what I did , and I switch of the D-S 2 and the use the Parasound Halo and then when I used the D S -2  I turn off the Parasound this way I get to use my main speakers , However I was wondering if their is any harm to the electronics, So I disconnected the Parasound and use a 2dry set of Kef LS 50  speakers . although the set up seemed to be working fine !
WOW a VAC for buffer pre amp !!! that is impressive

DaveC113

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thank you ,
But it works ? what I did was use the XLR with the Parasound Halo and the Kismet amp. and the RCA  outputs to the RCA inputs of Kismet from  the Don Sach's 2 pre-amp , I just turn off one unit and the other unit just works fine , vis versa , but I am wondering if their is any harm to it ?

I'd only have one plugged into the amp at one time... since there is no switch the unused cable is directly attached to the input and may act as an antennae and pick up noise. Not that you'd necessarily hear it as noise but it could cause a degradation in sound quality. It's either that or a switch, which will have a small effect.

With the XLR it's not a bad idea to see if the manufacturer of the pre recommends pin3 be floating or grounded. It's been a while since I looked but I think pin3 is floating, which is the safest option but it could be that grounding pin3 is better, or even using a resistor equal to the input impedance of the amp between pin3 and pin1. Probably TMI but since we're on the subject... ;)

Elizabeth

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WOW a VAC for buffer pre amp !!! that is impressive

I first bought a small cheap Chinese buffer. (It was useless for my desires)

So I was hunting around for a reasonable used tube preamp to use as a fancy buffer.. I saw a VAC Standard for $1,400. on Audiogon. I had no idea what VAC was at the time, but in a few minutes of research I discovered it was an early model from a pretty fancy $$$ company.. So I bought it.
The person selling it had purchased it used and arrived not working. He sent it to VAC.. which was taking too long for the repair (to him) and he bought another better preamp in the wait period. So I got a VAC factory refreshed and upgraded with better parts (some capacitors and remote added).. for a 1/4 of it's new cost plus upgrades. Great deal.
And for everyday listening.. It is perfect to buffer my older DAC.

Delta77

I'm a little confused on mixing Balanced and RCA connectors on the same cable..

  (1) Can I do it ?

  (2) Would there be any advantage using cables with mixed connectors in my set up ?
        OPPO (Balanced to RCA)  Candela preamp  (RCA to Balanced) Stratos amp

  (3)  Is it safe bypass the preamp and go strait from OPPO to Stratos via Balanced connections on both ends ?

My set up :
OPPO 205. (RCA to RCA) ODYSSEY Candela (RCA to RCA) Stratos 2 ch amp. 

 The OPPO has both Balanced and RCA outputs ,,
 The Candela (preamp) has RCA connectors only ,,
 The Stratos (amp) has RCA and Balanced inputs (not truly Balanced ? )..

Elizabeth

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I'm a little confused on mixing Balanced and RCA connectors on the same cable..

  (1) Can I do it ?

  (2) Would there be any advantage using cables with mixed connectors in my set up ?
        OPPO (Balanced to RCA)  Candela preamp  (RCA to Balanced) Stratos amp

  (3)  Is it safe bypass the preamp and go strait from OPPO to Stratos via Balanced connections on both ends ?

My set up :
OPPO 205. (RCA to RCA) ODYSSEY Candela (RCA to RCA) Stratos 2 ch amp. 

 The OPPO has both Balanced and RCA outputs ,,
 The Candela (preamp) has RCA connectors only ,,
 The Stratos (amp) has RCA and Balanced inputs (not truly Balanced ? )..

Really should have started a new thread for this question.

But..
(As an aside, but not good for your issues...
It is easy to split up a XLR out into two separate RCA. Using the XLR positive and ground for one RCA, the negative and ground for the other RCA. Best to use two full RCA cables, with the wires from a XLR body.
Remember the negative/ground is in reverse polarity compared to the positive/ground RCA.   For the opposite, taking a RCA to an XLR, you only can get 1/2 of the signal anyway. The positive, and the ground. You have NO negative signal to work with))

But in reality for your purposes..
There is NO advantage to trying to force use of the connections mix. Use the RCA.. period. I promise you will not find any magic trying to screw around with modified XLR/RCA cables. And you may find out screwing around just cost you $$$ because you blew something to Hell.

The CD to amp is no problem, but either the CD player or the amp MUST have a volume control.
One problem may be the CD direct to amp may not sound right. (typically lean) due to mismatch impedance. issues but there is a danger of the CD being turned on at full volume and blowing up your speakers or amp with the full volume blast prior to your jumping up to turn it down... If you have EVER done it,, you will avoid the possibility.. Trust me.

Delta77

Really should have started a new thread for this question.

But..
(As an aside, but not good for your issues...
It is easy to split up a XLR out into two separate RCA. Using the XLR positive and ground for one RCA, the negative and ground for the other RCA. Best to use two full RCA cables, with the wires from a XLR body.
Remember the negative/ground is in reverse polarity compared to the positive/ground RCA.   For the opposite, taking a RCA to an XLR, you only can get 1/2 of the signal anyway. The positive, and the ground. You have NO negative signal to work with))

But in reality for your purposes..
There is NO advantage to trying to force use of the connections mix. Use the RCA.. period. I promise you will not find any magic trying to screw around with modified XLR/RCA cables. And you may find out screwing around just cost you $$$ because you blew something to Hell.

The CD to amp is no problem, but either the CD player or the amp MUST have a volume control.
One problem may be the CD direct to amp may not sound right. (typically lean) due to mismatch impedance. issues but there is a danger of the CD being turned on at full volume and blowing up your speakers or amp with the full volume blast prior to your jumping up to turn it down... If you have EVER done it,, you will avoid the possibility.. Trust me.

Thanks for the totally informative answers..( easy to understand )..
Your answers fall right in line with my gut feeling,,
And I think your dead on with the OPPO directly connected to the amp , in relationship to Both the Impedance imbalance,  and the Max volume Danger ..

A_shah

Thanks for the totally informative answers..( easy to understand )..
Your answers fall right in line with my gut feeling,,
And I think your dead on with the OPPO directly connected to the amp , in relationship to Both the Impedance imbalance,  and the Max volume Danger ..
Burt,
Call OPPO tech support and they may confirm this,  I believe your OPPO 205 can be directly connected the Stratos, you can use the XLR between the Stratos & the OPPO, not sure about the impedance thing , but Klaus probably put in WBT input to your Stratos (my Kismet has the top of the line WBT's )
So really their is no advantage to you unless you have a very long run say 15 feet or more, than XLR come into play  to reduce noise as they are active and balanced on the OPPO ,
My case was different, I wanted to use the same power amp. Kismet with two different pieces of equipment basically "shutting one off "when the other one is use. , since Don Sachs' pre-amp has a switch in the front to switch it off , that simply left Parasound with XLR to feed the Power amp when the other pre-amp stays shut. it worked fine but their was some sort of an antenna  effect,  for some reason my sub woofer attached to the DS 2 input/out puts would continue to be active when I used Parasound despite the fact the DS 2 was shut off ! although did not find the  sound bad or distorted, when I pulled the PC of the D S 2 it was still their,  except not that much volume , So  I simply disconnected the Parasound XLR and used my 2dry KEF Speakers with the Halo and let Don's pre-amp and Stratos/Kismet work with  my Maggie !.7i, I just put 2.25" x 24 X 18  Boos Maplewood Blocks under the speakers  from Amazon, boy or boy not only did they clean up my Hi frequencies but gave me very good Bass , voice/ Vocals are so clear !

Armaegis

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I just want to chime in that the safest way to convert XLR to RCA is with a transformer.

Most of the time, splitting an XLR balanced signal into two single ended ones (of opposite phase) can work... however, there are a few devices out there where doing so will release the magic smoke. The same can be said for converter cables that ground the negative pin of the XLR.