Gilmore Reference Balanced?

[Torpedo]

It's not about preserving absolute polarity, which AFAIK is preserved in my system, since listening with phones I can't really say if it's "correct" or not, even less considering many recordings have it completely messed up.

My interest comes from knowing if using both SE outputs at the same time I'm loading the same amplification rails, or each phone would be using a rail for its own. As I see it, having each SE output using different phases of the balanced configuration, would be the same as having two separate SE amps, one with opposite signal polarity than the other one.

Rgrds

[n_maher]

I think only Justin can answer this unless there's a detailed internal picture that you can point me to.

[Torpedo]

I think only Justin can answer this unless there's a detailed internal picture that you can point me to.

Thanks Nate. I don't have detailed pics other than the ones Justin posted at the beginning of the thread. Let's see if Justin shows up later and wants to clarify. Otherwise I can open my unit and try to get some decent pics, or just see for myself if sound quality suffers any changes by plugging a second pair of phones into the other output. On the Rudi this has a very clear impact in the sound.

Rgrds

[luvdunhill]

Thanks Nate. I don't have detailed pics other than the ones Justin posted at the beginning of the thread. Let's see if Justin shows up later and wants to clarify. Otherwise I can open my unit and try to get some decent pics, or just see for myself if sound quality suffers any changes by plugging a second pair of phones into the other output. On the Rudi this has a very clear impact in the sound.

Rgrds

perhaps due to change in output impedance with a capacitor coupled amp? more likely than phase, IMHO.

[Torpedo]

I never thought the change in sound on the Rudi had anything to do with phase. IMO it's for additional load. Not sure if the RPX-100 is capacitor coupled though. I think both outputs use the same amplifier section.

Rgrds

[justin]

the 1/4" outputs are in parallel and connected to the + phase

[Torpedo]

the 1/4" outputs are in parallel and connected to the + phase

Thanks a lot for replying Justin That was my guess.

I'm quite pissed, I haven't been able to listen with HPs in the whole afternoon. I'm waiting for a delivery, if I use phones I don't hear the street door intercom bell, so here I am with a new toy not being able to enjoy it

Rgrds

[spritzer]

I never thought the change in sound on the Rudi had anything to do with phase. IMO it's for additional load. Not sure if the RPX-100 is capacitor coupled though. I think both outputs use the same amplifier section.

Rgrds

The RPX-100 has a capacitor coupled output and changing the load impedance will therefor have a large impact.

[justin]

The RPX-100 has a capacitor coupled output and changing the load impedance will therefor have a large impact.

it would also be a large impact if the amplifier has a high output impedance

[Torpedo]

The RPX-100 has a capacitor coupled output and changing the load impedance will therefor have a large impact.

Yes it has, and not only in the volume level . Fortunately we seldom use two phones at the same time.

[luvdunhill]

ah, a load dependent amplifier.. real quality stuff.

[spritzer]

ah, a load dependent amplifier.. real quality stuff.

It's better then an ESP amp that damages the phones it's driving. Rudi sure makes quality stuff...

[Torpedo]

It's better then an ESP amp that damages the phones it's driving. Rudi sure makes quality stuff...

You're really bad guys The RPX-100 could be better made and using better parts for the price, but soundwise isn't a bad amp provided you use the "high-gain" output and just a pair of phones loading it.

It is quite powerful and manages to drive any of my cans efficiently, with a nice "I'm not here" character, I mean that it lets my sources offer their sound which I know well after several years together, and also allowing you to hear the cans own signature. However I'm quite sure there're more affordable options delivering all that. It's just that I haven't tried them

[n_maher]

I think the general problem with it is the ~$3k price tag coupled with such steller specifications as:

Humm Level : Not measurable

[cclragnarok]

Actually, the KGSS specification also says that the SNR is "inaudible."

Of course, inaudible is not really the same as not measurable.

[luvdunhill]

The RPX-100 could be better made and using better parts for the price,

better parts? doubtful. Better schematic and builder? definitely

[justin]

Actually, the KGSS specification also says that the SNR is "inaudible."

Of course, inaudible is not really the same as not measurable.

Unless you own some very expensive test equipment, easiest way to test SNR is to just plug in a super sensitive pair of IEMs and listen for hiss/hum. If nothing can be heard, you have a very, very good SNR.

[cclragnarok]

Unless you own some very expensive test equipment, easiest way to test SNR is to just plug in a super sensitive pair of IEMs and listen for hiss/hum. If nothing can be heard, you have a very, very good SNR.

I'm not sure I want to do that with my KGSS. Otherwise, as an UM2 owner, I agree with you.

[spritzer]

The SR-003 is very sensitive...

[cclragnarok]

The SR-003 is very sensitive...

I probably shouldn't try one of those then. I find the gain on my KGSS to be too high even for the Omega IIs.

[spritzer]

I probably shouldn't try one of those then. I find the gain on my KGSS to be too high even for the Omega IIs.

The gain isn't the problem, more likely your source is too hot i.e. its output level is above the 2v(4v) spec. That can be fixed by attenuating the signal before it enters the amp. There was a thread on this a few months back...

[cclragnarok]

The gain isn't the problem, more likely your source is too hot i.e. its output level is above the 2v(4v) spec. That can be fixed by attenuating the signal before it enters the amp. There was a thread on this a few months back...

Actually, I guess the main problem is that the stepped attenuators don't have enough steps. I'm always on the first few steps, and I think they are spaced farther apart than the steps in the middle.

I just bought an Echo Audiofire 2, which will hopefully work well as a 24-bit computer transport. I will then use foobar to make small adjustments in volume.

[spritzer]

Don't get me started on the steppers... You can always add inline attenuators to drop the level and they are cheap-ish.

[cclragnarok]

Don't get me started on the steppers... You can always add inline attenuators to drop the level and they are cheap-ish.

That might be the best solution if the problem is bad channel balance at low volume on pots.

With the stepped attenuators, channel balance is not an issue. The only problem is the size of the steps. Even if an inline attenuator is used to move me to the middle steps, the steps might still be large enough to annoy me.

Assuming that the implementation of the foobar v0.8.3 volume control is good, it should not degrade sound quality much if I have a 24-bit transport, and I only make small adjustments there. I can set up keyboard shortcuts to adjust the volume 0.5 dB at a time, so it should be pretty convenient except for the fact that it'll only work when foobar is on top.

Like I mentioned in another thread, none of my previous 24-bit computer transports (Transit, 0404 USB, etc) worked without clicks and pops when I have my wireless card enabled. Fortunately, my Echo Indigo DJ had a huge hardware buffer (IIRC, it buffered up to ~25 seconds), so the Audiofire 2 should work fine if its buffer is even close to that size.

[spritzer]

I'd take a small drop in fidelity (if any) on the Foobar side rather then loathing the amp.