[eddiek997]

I have a Tube Amp that I use for my 2channel system and am itching to try this out with my HE500s - I do love that tubey warmth.
The amp is an Onix SP3 MKii with 38wpc output into 4/8 ohms. It has fully rolled NOS tubes and sounds fantastic with my B&W CM7's but when my kids are asleep, headphones are needed.
 
The manufacturer has since gone out of business (despite this fantastic value for money and wonderful looking amp) and I have no way of knowing if they used a common or floating ground system. Because it's a tube amp, my understanding is that you shouldn't run it without a load connected to the speaker outs and therefore cannot just put a meter across the negative terminals and check for continuity.
 
I could just buy a balanced cable and be done with it but, I JUST bought a moon audio blue cable (Furutech 1/4 jack, not balanced) and really don't want to buy another cable as I love my setup with the Lyr/Bifrost with Siemens CCa tubes. HOWEVER, I really want to find out how good/bad the HE500's sound from the Onix.
 
Should I just as BTG audio to make me a jumper cable with 1/4inch Female to 4 conductor speaker cable (so I can keep using the Moon cable) and risk damaging the 500's or can anyone see another solution to
a. minimize risk.
b. minimize cost.
c. both.
 
 
Thanks in advance for your time should you reply....

 

 

• Preamp: 12AX7
• Phase Inverter: 12AU7
• Driver: 6922
• Power: 5881

 

[eddiek997]

Incidentally, for those who are interested in completely maximizing their HE500's, this thread (jergpad mod) is essential reading.
 

 

[weverb]

Quote:

Should I just as BTG audio to make me a jumper cable with 1/4inch Female to 4 conductor speaker cable (so I can keep using the Moon cable) and risk damaging the 500's or can anyone see another solution to a. minimize risk.
b. minimize cost.
c. both.

 
Beautiful looking amp. Maybe the combo of these items would work?
 
http://www.amazon.com/HOSA-STEREO-PHONE-1-TIP-1-RING/dp/B000068O5C/ref=wl_it_dp_o_pdT1_S_nC?ie=UTF8&colid=1LG5QC765M7N&coliid=I1GY0VPL2NAMKI
 
http://www.amazon.com/IEC-1-Feet-Speaker-Wire-Males/dp/B003U48NIY/ref=wl_it_dp_o_pC_nS_nC?ie=UTF8&colid=1LG5QC765M7N&coliid=I2YZ2XILB93S3F

 

[zilch0md]

Quote:

 
Beautiful looking amp. Maybe the combo of these items would work?
 
http://www.amazon.com/HOSA-STEREO-PHONE-1-TIP-1-RING/dp/B000068O5C/ref=wl_it_dp_o_pdT1_S_nC?ie=UTF8&colid=1LG5QC765M7N&coliid=I1GY0VPL2NAMKI
 
http://www.amazon.com/IEC-1-Feet-Speaker-Wire-Males/dp/B003U48NIY/ref=wl_it_dp_o_pC_nS_nC?ie=UTF8&colid=1LG5QC765M7N&coliid=I2YZ2XILB93S3F

 
Hey, thanks for that first link weverb!   

          
I had looked hard  for a stereo 1/4-inch TRS female to dual RCA male adapter, but couldn't find it.  All I could find was the 3.5mm stereo female equivalent.
 
Unfortunately, that second link won't work with the adapter at the first link:
 

 
 
You would need to insert one of these:
 

 
http://www.amazon.com/RCA-Jacks-Inline-Coupler-AH210N/dp/B00005T3G5
 
 
 
 
       - OR -
 
 
You can use this combination of adapters:
 

http://www.amazon.com/IEC-1-Feet-Speaker-Wire-Males/dp/B003U48NIY
 
 

 
http://www.amazon.com/Parts-Express-Stereo-Female-Adapter/dp/B000TTHVYK
 
 

 
http://www.amazon.com/Planet-Waves-Female-Stereo-Coupler/dp/B0002E52S4
 
 
Disclaimer:  Both combinations REQUIRE that the speaker amp's terminals share a common ground, as is the case with the Emotiva mini-X 
 
Thanks,
 
Mike
 
UPDATE:  I've found what appears to be a higher quality, yet less expensive substitute for speaker wire to RCA adapter shown above:
 

 
http://www.amazon.com/gp/product/B009B8EJYU

 

[eddiek997]

Quote:

 
Beautiful looking amp. Maybe the combo of these items would work?
 
http://www.amazon.com/HOSA-STEREO-PHONE-1-TIP-1-RING/dp/B000068O5C/ref=wl_it_dp_o_pdT1_S_nC?ie=UTF8&colid=1LG5QC765M7N&coliid=I1GY0VPL2NAMKI
 
http://www.amazon.com/IEC-1-Feet-Speaker-Wire-Males/dp/B003U48NIY/ref=wl_it_dp_o_pC_nS_nC?ie=UTF8&colid=1LG5QC765M7N&coliid=I2YZ2XILB93S3F

Thank you,
 I did see these listed earlier in the thread but I see that the Hosa TR adapter uses 24awg which is basically cat5 and that seems highly undesirable for high(ish) end audio requirements.... Still worried about combining the grounds....

 

[eddiek997]

aha... I found a schematic for the amp... now to decode it and see if it does indeed share a common ground..
 

 

[eddiek997]

So....
I had a 1/8th stereo to rca stereo breakout adapter and a 1/8 to 1/4 cable lying around and did this..
 
Cut the rca jacks off the 1/8 to stereo cable

 
Strip back the jacket from the signal side of the wire (the ground is bare)
 

 
Terminate with banana plugs (grounds to black connection)

 
Connect the 1/8 to 1/4 adapter cable..
 

 
Plug in my regular cable to the female 1/4 and give it a whirl...
 
Should work right?

 

[Armaegis]

Yeah it should work as long as the amp has a common ground. 

 

[eddiek997]

Thank you.
 
Tried it first on my trusty old Sansui 5050  (although the signal meter doesn't work)
 

 
I was nervous at first (im sure you all were) and was very taken aback by the presence, definition of the lows and mids but was very bright at the top with sibilance clearly evident. But then I started noticing the voice coil in the left side was putting so much pressure on my ear that I could actually feel it.
Unplugged immediately and went into the 5050/s headphone jack but the sound was awful.
 
I know this thread was about the Emotiva but I think that the type of amp was incidental, it was more about $$ as opposed to $$$$$$ and the Sansui cost me $50 3 yrs ago on flea bay so I think that counts.
Now, onto the SP3 tube amp....

 

[Happy Camper]

You are going to fall in love with that tube amp with those 500s. Plenty of power but that tube goodness.........Insert big drool here..........

 

[eddiek997]

Quote:

You are going to fall in love with that tube amp with those 500s. Plenty of power but that tube goodness.........Insert big drool here..........

Believe me, that amp with the B&W's make me a, well, Happy Camper. Ear to ear smile, goosebumps kinda stuff.

With the kids in bed though, out come the cans.....

I was about to try it earlier but the pigtail I made with the banana plugs doesn't have enough cable to span the left and right sides of the amp (binding posts are about 6" apart and I made a 3" cable (story of my life 3 inches short of a useful pigtail))..
 

 

[eddiek997]

@armaegis - Thank you - I put a multimeter in continuity and touched the two negative terminals and got confirmation that there's a common ground. I'll extend the cable tomorrow and try it then.
 

 

[eddiek997]

2nd attempt at home made cable.
 
I found a Radio Shack 1/4inch female to stereo rca breakout cable. Cut the ends off, stripped back and terminated with some Monster quick lock banana plugs I had lying around (I like that they have a rubber insulator so I don't inadvertently short them together). 5 minutes total...
 

 

 

 

 

 

[weverb]

Quote:

 
Hey, thanks for that first link weverb!   
          
Unfortunately, that second link won't work with the adapter at the first link:

Disclaimer:  Both combinations REQUIRE that the speaker amp's terminals share a common ground, as is the case with the Emotiva mini-X 
 

 
Your welcome.
 
Sorry, thought the adapters were implied as both ends had male connections. Will spell out next time.

 

[weverb]

Quote:

2nd attempt at home made cable.

 
And the listening results are.....

 
I still have not gotten brave or purchased the parts to try this on my Simaudio integrated. Keep getting tempted reading this thread. Keep thinking about just buying the HifiMan 5m cable and cutting the end off.
 
http://www.head-direct.com/Products/?act=detail&id=139