Help and opinions needed on pre-amp situation


For this one, I would like to hear from enthusiats instead of people who sell stuff. I’ve been using integrated amplifiers for all my years in this "hobby." I recently went to mono blocks- a pair of the class D Atma-Shpere’s to be specific. I’m using balanced XLR connections straight from a Lumin S1 streamer/dac/preamp into the mono blocks using Lumin’s LeedH volume processing deal. It’s a nice and simple setup with nothing else in the signal path.

The question is: am I missing out on better sound by leaving out an Atma-Sphere MP-3.3 tube preamp? Will adding a preamp improve, diminish, or retain the existing sound quality- as far as soundstage, imaging, depth, tonal balance etc is concerned? This preamp deal is not cheap (for me). Has anyone been in this situation? Did the preamp improve the sound, keep it the same, or make it worse? Am I better off just leaving it as-is with my minimalistic setup?

A couple of other things to consider:

My turntable is collecting dust since changing over to the mono blocks, I didn’t listen to vinyl often even with the integrated since my digital front sound better then my vinyl gear. If it made $ense, it would be nice to have the ability to listen to vinyl again.

At some point I may also have to connect a projector to my system to play audio. Then the issue becomes that projectors do not have balanced XLR output. Most are HDMI. I’m not sure if the MP-3 preamp will work or if a different preamp is better choice here etc. I’d like to keep with the same brand for obvious reasons if possible.

Has anyone been in this situation before and pulled the trigger? If you have- your input, suggestions, and opinions would be greatly appreciated.

veerossi

A great preamp will add the musical richness to a system 99% of the time. The systems that sound better without are a real rarity. In the rare occasions that they are not required, I suspect they belong to folks that appreciate detail over musicality. Because without a good pream the sound tends to sound highly detailed and a little dead.

@veerossi To add the phono section to the MP-3 is inexpensive if its ordered that way.

Regarding sound quality there are a number of variables. The most common thing you run into is that most of the balanced line equipment made for high end audio does not support the balanced standard even though it might really be balanced.

As best I can make out, the Lumin is an example; I say this because the balanced output has twice the voltage of the single-ended; if it supported the standard the voltage would be the same. One of the goals of the balanced line system is to eliminate ground loops and this is done by ignoring ground in the balanced connection insofar as the signal is concerned. The RCA connection does not ignore ground; when you see the voltage double what it usually means is that the RCA connection is one of the two XLR outputs (probably the non-inverted output, pin 2 of the XLR) and there is a second circuit that creates a single-ended inverted signal for pin 3 of the XLR. What's happening here is both signals reference ground.

The MP-3 doesn't do it that way. Its output, although direct coupled, acts very much like a simple line transformer with only 2 wires at its output- one tied to pin 2 of the XLR and the other to pin 3 with no connection to ground. So the advantage might be that the MP-3 can control the interconnect better, reducing artifact that the cable might otherwise have (and of course one of the advantages of that is you can run really long interconnects, allowing your speaker cables to be as short as possible; at home my amps sit on top of my speakers...). Of course if you have any other sources like a turntable or tuner then the advantages of a preamp are magnified. I use my DAC to accept HDMI for the home theater.  

 

@veerossi

I am kind of in the same boat as you , do I need or want a preamp ?

I currently have a passive pre with input select and a stepped attenuator .

The question is what do I want from an active preamp ?  I already know that it has to have a stepped attenuator , I would like to have a mono/stereo switch and a balance control ( for older mono records ) but do I need gain ? If so how much ? I'm still on the fence about tube or SS since the phono pre is tube and the CD player has tubes in the output .

So you have to ask yourself what do you want or need ?  Tone controls ? left/right speaker switch , reverse polarity , a/b speakers or the same that I am looking for ?  

A preamp is for input switching. Goods ones are neutral.

Unless you are searching for a tone control.

Go to Ralph with your needs and desires.

Tnanks for the responses. Keep em' coming.

I have no idea how good or bad the Lumin Leed h voume control is in the grand scheme of things. The Lumin S1 was their top of the line/flagship offering prior to the X-1. In the menu it has a setting for "Analog Output Level" and has "Normal" or "Low" for choices. Not sure if that has anything to do with what @atmasphere Ralph mentioned about the balanced output.

Seems like results can vary quite a bit and nothing definite either for or against a preamp. This is going to turn into an experiment. Yes, @vair68robert: I don't care what people have to say: tone control would be great and same goes for balance and a/b speakers, channel gain (MP-3 has this), balanced, tube, and with a remote control for volume. 

I see PS audio has a no hassle trial period. Upscale Audio has a trial also, but not sure if theirs is hassle free or credit towards something else, restock, etc. Any input on the BHK preamp? I also have my previous integrated amp that I need to sell. PS audio take trades, so maybe that could workout. Moonshot here, but if anyone in Socal has an MP-3 sitting around that I can borrow, let me know. I'll pay. That would be fantastic and would put this whole thing to rest. If you know any other companies offer a no hassle/ no strings attached trials, please let me know. Whether new or used, I am not interested in purchasing something to find out waste of money and then be stuck with sitting on it and having to deal with selling it. Also what about these Vincent ones or Zesto? Will they be synergistic with Atma-Sphere or should i only stick to Atma-Sphere since that's probably what they are designed for?