Review: PreSonus Central Station (DAC, Preamp, Headphone Amp)

[Ferbose]

Quote:

Originally Posted by Naga crAp, so the headphone amps dont get any benefit from the master volume and it's resistor-chain volume control ( which seems to behave like a stepped attenuator in many respects ) hmm - im curious if the headphone amp circuits on this are related to those in the HP4 edit, i just remembered talking to someone about balanced 580s out of the HP4's monitor out - would only be that much sweeter running balanced out of the speaker outs on this w/ that kind of volume control another question, what are the " speaker trims" and what are they usedfor?

Headphone amplifier is an active device. It will need its own volume pot no matter what. There is no benefit for it to receive signal from the passive volume control circuit.

Speaker trims are variable resistors that can be used to adjust the relative levels of L and R channels, to get stereo balance.

 

[Ferbose]

Here is a good link to explain how passive preamps work and the common pitfall of such designs.
http://www.soundstage.com/articles/pete02.htm

After reading the article above, it should be clear that PreSonus Central Station's volume control is very different from stepped attenuatotrs. A normal stepped attenuator is just a replacement for rotary potentiometers. Using it instead of a rotary potentiometer does not alleviate any of the impedance matching problems that plague passive preamp designs.

Consider, for instance, the circuit in fig. 1b in the linked article. To obtain desirable impedance values, the resistor in-series with the volume pot should also change as volume pot's resistance changes. In most passive preamp designs, it is not possible to swap the series resistor, and hence optimal impedance at different volume settings cannot be achieved. Using a stepped attenuator instead of a rotary potentiometer does not solve this problem at all.

To change series resistor values, one has to lay down a bunch of resistors and use relays to swap each resistor in or out of the signal path. Once there are resistors and relays, there is no point in using a rotary potentiometer or stepped attenuator, because their function can be replaced by a bunch of fixed-value resistors and relays. This is why PreSonus Central can use only resistors and relays in the signal path to attenuate signal. It seems clear to me that the best solution to passive volume control is using resistors and relays.

 

[Ferbose]

I took Central Station to 2006's first So-Cal meet, and did quite a few A/B comparisons against other wonderful gears. Imagine my surprise when I found that its internal DAC can compete with Esoteric DV-50 and its heapdhone amp can compete with Grace m902. There were other head-fiers who also participated in these comparisons and shared the same opinions, so it's not just me going crazy. You can read more about these comparisons in post #1 here or at this thread:
http://www6.head-fi.org/forums/showp...52&postcount=8

 

[jvbb2005]

Quote:

Originally Posted by Ferbose I took Central Station to 2006's first So-Cal meet, and did quite a few A/B comparisons against other wonderful gears. Imagine my surprise when I found that its internal DAC can compete with Esoteric DV-50 and its heapdhone amp can compete with Grace m902. There were other head-fiers who also participated in these comparisons and shared the same opinions, so it's not just me going crazy. You can read more about these comparisons in post #1 here or at this thread: http://www6.head-fi.org/forums/showp...52&postcount=8

Thanks for the update. Now you are driving up the prices of Central Station at ebay

Will be nice if more head-fiers who had the luck to attend the So-Cal meet to chim in to give their opinions. I need more reviews to support my decision to spend 500 bucks on a piece of audio gear which I never had a chance to hear.

 

[jvbb2005]

One more question, Ferbose. I don't think you have answered me where CentralStation is made. Does it say on the retail box?

 

[Ferbose]

Quote:

Originally Posted by jvbb2005 One more question, Ferbose. I don't think you have answered me where CentralStation is made. Does it say on the retail box?

Mine is made in China.

To audition Central Station, smply buy it at Guitar Center.
At my local Guitar Center, the salesperson gave me a discount so it is $500 after tax. And since the box is not sealed, he said I can return it without re-stocking fee if it look snice. This way, it is the same price as buying online, and I get a two-week test period. I ended up keeping it.

 

[ssingh0]

doesn it have a preamp with phantom power for condensor microphone?

 

[Ferbose]

Quote:

Originally Posted by ssingh0 doesn it have a preamp with phantom power for condensor microphone?

No, it is not a microphone preamp.
It has a built-in mike and a mike input for communications in the studios.

 

[ssingh0]

Quote:

Audiophiles not on a budget should still check out its preamp function

I thought preamp was only used for speakers... what benefit does it hold for head-fiers?

 

[Ferbose]

Quote:

Originally Posted by ssingh0 I thought preamp was only used for speakers... what benefit does it hold for head-fiers?

Head-fiers are not limited to music enjoyment only on headphones.

Who said it can't be used for headphones? For example, you could connect two monoblock tube power amps to it, and drive K1000.

In my own case, I often listen to speakers and K1000 simultaneously, using three integrated amps at the same time. I bought Central Station as a master volume control feeding signals to all three amps. It is an awesome experience and probably the best way to enjoy K1000. Credit WMCamus for discovering this, LOL

 

[ssingh0]

Quote:

speakers and K1000 simultaneously,

?

 

[Naga]

thanks so much Ferbose!

I have an HP4, and I think this thing can out do the DAC in my emu 0404; hopefully soon I can try the Central Station for myself.

EDIT: Have you tried the HD 580 or 600 w/ the Central Station?

 

[Ferbose]

Quote:

Originally Posted by Naga Have you tried the HD 580 or 600 w/ the Central Station?

Only briefly at the meet. No problem there.

 

[Naga]

one last question, i notice it's digital inputs section is labeled 192 KHZ / 24bits - it can still accept a normal 44.1 KHZ cdplayer/dvd player right?

 

[Ferbose]

Quote:

Originally Posted by Naga one last question, i notice it's digital inputs section is labeled 192 KHZ / 24bits - it can still accept a normal 44.1 KHZ cdplayer/dvd player right?

Definitely.