[Holy Zoo]

Unlike my first thread, I hope this is in the right forum.

So, still on my search for a headphone amp.

In the running at the moment are:

Creek OBH-11 (no crossfeed, of course)
Corda Headamp
Headroom Little

I've been poking around head-fi and elsewhere reading up about the benefits of cross-feed - I think I have a basic handle on things... except for one thing...

I've read that a time delay can (should?) be part of a cross-feed circuit - but isn't required.

So, I'm not certain if a time delay is part of the Corda and Headroom amp's cross-feed circuit.

If there *is* a time delay in one/either of these amps, it brings on another question: how do they do the time delay? I'd be most worried if they did it via a digital delay. Since my source will be a Sony SACD player, I'd really like to introduce a "low" quality digital delay to the mix.

thanks for any enlightenment you might provide!

 

[DanG]

I'm not sure I understand what you mean by a "digital delay." If you are asking whether any delay used in making a more natural crossfeed is part of a digital decoding algorithm, it is not, since all three amplifiers mentioned do not take a digital signal, but an analogue one.

 

[Holy Zoo]

Quote:

Originally posted by DanG If you are asking whether any delay used in making a more natural crossfeed is part of a digital decoding algorithm, it is not, since all three amplifiers mentioned do not take a digital signal, but an analogue one.

The amp may only take a analog signal, but that doesn't mean that it can't do digital processing "inside the box" to perform a time delay.

 

[Rotareneg]

The Corda (which I have), uses a passive filter, while Headroom amps, such as the Total Airhead (which I also have) use an active filter. They're both completely analog, no digital processing involved. The delay is caused by the phase shift as the crossfeed signal goes though the filter circuit.

 

[KurtW]

Rotareneg is correct, the delay is analog in both. One difference is that the Corda will not change the balance of the sound when you switch in the crossfeed, whereas the HeadRoom will boost the bass slightly. The theory is that bass that is in one channel only will be reduced when you use crossfeed, but bass is usually in both channels. I've never noticed a bass reduction on any music in the Corda, but the bass boost is always noticable in the Headroom. The treble is cut as well with the crossfeed on in the HeadRoom, but all but the airhead series have a switch that mostly restores the treble. There is some ripple in the frequency response curve due to comb effect of the active filter, but it's fairly small and not very noticable. Another difference is Headroom designs in a very slight rolloff in the very high frequencies, where the Corda is super flat, with or without crossfeed. Of course, even without the crossfeed circuits, the two amps will sound slightly different due to the different op amps they use, etc.

 

[Holy Zoo]

Thanks Rotareneg, for the answering my question (and aleviating my fear)!

Kurt - thanks for the info on the HeadRoom's bass boost.

Reading on the HeadRoom site, they state the following about the redesigned amps:

Quote:

Supreme, Cosmic, Home, MaxedHome, Max, and MonoMax now sport High/Medium/Low gain switch to optimize volume setting for headphones of differing efficiencies, and a re-designed, High/Low/No high frequency boost filter switch delivers improved coherence and better user selectability.

Does anyone have one of the new models? (are they even out yet?). I'm wondering if the new filter switches address Kurt's concerns.

 

[nick danger]

I'd like to know if someone has compared the Creek OBH-11 and the Corda amps. From what I have read they are both pretty flat with satisfying bass presence. If the difference between the two is the crossfeed, I'd be willing to go for the Corda. Any reviewers of both amps?

 

[legoman]

Quote:

Originally posted by nick danger I'd like to know if someone has compared the Creek OBH-11 and the Corda amps. From what I have read they are both pretty flat with satisfying bass presence. If the difference between the two is the crossfeed, I'd be willing to go for the Corda. Any reviewers of both amps?

I second that. A comparison of both would be a great thing, especially for all of us that are low on cash....

legoman

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"...because without crossfeed things don't sound so relaxed"