Folks,
I borrowed a XP-12 PL preamp this past weekend in order to compare SQ with the preamp and without (just using Topping D90LE). I've been using the D90LE connected directly to the X150.8 amp since the tube BAT preamp was not cutting it (see previous comments).
To no surprise the D90LE direct connection is still preferred at this point. Where the sound stage / depth was expansive with the D90, everything shrank noticeably with the XP12. Aside from music tracks I've run some Chesky stage depth and width test tracks, which produced similar test results. Compared to the BAT with the X150.8, there was less haze with the PL preamp. The XP12 did solidify vocals and instruments to an extent. But I would also say (and probably the biggest takeaway) in general I felt the XP12 was not as engaging compared to the D90, or with the BAT amp/preamp combo I used to have (yes the distortion🙂 When I found new tracks on Qobuz that sounded well recorded, after demoing on the XP12, I immediately wanted to remove the unit to get a sense of how the tracks were different. Always found that they were enjoyable without the preamp.
Even though I miss some tube power amp attributes, I will say having the PL X150.8 in the system (with just the DAC) is providing certain levels of engagement and fun, especially lower registers. There is always the XP-22 to try out (2-chassis), but price wise doesn't make sense since it would have to be highly engaging to override what is in the system now.
Tweaking what I have (X150.8/DAC) is more interesting right now, but would look to experiment with other lo gain/options that are balanced switchable inputs and with a remote. I may take a look at some of the low noise Topping headphone amps with adjustable gain settings.
I borrowed a XP-12 PL preamp this past weekend in order to compare SQ with the preamp and without (just using Topping D90LE). I've been using the D90LE connected directly to the X150.8 amp since the tube BAT preamp was not cutting it (see previous comments).
To no surprise the D90LE direct connection is still preferred at this point. Where the sound stage / depth was expansive with the D90, everything shrank noticeably with the XP12. Aside from music tracks I've run some Chesky stage depth and width test tracks, which produced similar test results. Compared to the BAT with the X150.8, there was less haze with the PL preamp. The XP12 did solidify vocals and instruments to an extent. But I would also say (and probably the biggest takeaway) in general I felt the XP12 was not as engaging compared to the D90, or with the BAT amp/preamp combo I used to have (yes the distortion🙂 When I found new tracks on Qobuz that sounded well recorded, after demoing on the XP12, I immediately wanted to remove the unit to get a sense of how the tracks were different. Always found that they were enjoyable without the preamp.
Even though I miss some tube power amp attributes, I will say having the PL X150.8 in the system (with just the DAC) is providing certain levels of engagement and fun, especially lower registers. There is always the XP-22 to try out (2-chassis), but price wise doesn't make sense since it would have to be highly engaging to override what is in the system now.
Tweaking what I have (X150.8/DAC) is more interesting right now, but would look to experiment with other lo gain/options that are balanced switchable inputs and with a remote. I may take a look at some of the low noise Topping headphone amps with adjustable gain settings.
What about a stepped attenuator passive preamp? Maybe a nice unit from Khozmo would do the trick.
https://khozmo.com/product-category/preamplifiers/
There is also Zen Mod's Iron Pumpkin which could be very cool. But I agree with Zen mod. Adding more gain stages can cloud the sound a bit. However, in some cases, I have heard improvements with preamps in how they shape the sound to be better. Generally I like things direct.
The topping is a nice DAC. I have one. I would suggest putting the money towards another DAC or two to try different sounds. I got a nice DAC recently that I have been going through, playing with the circuit on and upgrading. It sounds phenomenal and stomps all over the topping D90 in my opinion.
https://khozmo.com/product-category/preamplifiers/
There is also Zen Mod's Iron Pumpkin which could be very cool. But I agree with Zen mod. Adding more gain stages can cloud the sound a bit. However, in some cases, I have heard improvements with preamps in how they shape the sound to be better. Generally I like things direct.
The topping is a nice DAC. I have one. I would suggest putting the money towards another DAC or two to try different sounds. I got a nice DAC recently that I have been going through, playing with the circuit on and upgrading. It sounds phenomenal and stomps all over the topping D90 in my opinion.
passive no
Iron Pre is a way, with or without autoformer, so no or with 6db gain, but in this case autoformer could bring some welcome flavor (taste dependable) but gain is more than not needed
though, in this particular case - if using only one source, no need for any interface
Cool, that makes sense. My only thought was that apparently digital attenuation is not supposed to be great. I haven't done any research real research on the subject though. Right now I am going from DAC into my amp instead of using a preamp as I think it sounds better.... So I suppose I am one to argue...
all roads are leading to Rome
best ones are those of your personal choice
best ones are those of your personal choice
Too much attenuation is not good, but also.....
https://archimago.blogspot.com/2018/09/musings-measurements-look-at-dacs.html
Cool. So under normal listening conditions with our 16dB+ gain amplifiers, it is not a problem... I am glad I didn't overthink it before.
At this point I do have a CD player (Oppo) and streamer (iFI Zen), and wanted a switching source with remote. It may be unfounded, but I did want a physical attenuator between the DAC and amp, in the case the digital volume glitched and cranked out speaker damaging sound. Attached is an old ESS "very" high level explanation of the digital vs. analog. I need to read Rayma's link since I do follow Archi's blog. Curious what DAC your enjoying.
I understand your concern. The topping D90 is a very reliable DAC that seems to be pretty failsafe. I would definitely not push and hold the volume button while music is playing as the volume changes too quickly IMO... I push it so it moves in single steps at a time. The D90 can put out I think 4v in balanced mode. The X150.8 is at max power at something like a 1.8v signal I think.
If you haven't had a problem up until now, I don't think that you will as these DACs don't seem to fail or glitch often as far as I am aware.
My other two DACs pop and make noises once in a while if the USB cable is dirty or in poor condition. The topping does not do that. If there is an issue with the digital signal, the DAC just cuts out and then comes back quietly.
Khozmo makes great stepped attenuators. I have one and it is my favorite of the three nice stepped attenuators that I have. If you want to play around with a passive preamp, that would be the route I would go. However, Zen Mod suggests not to bother and he has spent a lot of time playing attenuators.
If you haven't had a problem up until now, I don't think that you will as these DACs don't seem to fail or glitch often as far as I am aware.
My other two DACs pop and make noises once in a while if the USB cable is dirty or in poor condition. The topping does not do that. If there is an issue with the digital signal, the DAC just cuts out and then comes back quietly.
Khozmo makes great stepped attenuators. I have one and it is my favorite of the three nice stepped attenuators that I have. If you want to play around with a passive preamp, that would be the route I would go. However, Zen Mod suggests not to bother and he has spent a lot of time playing attenuators.
The current DAC is a Musical Fidelity A3.24 which started out as a complete underdog. it sounded okay... I have done some significant mods to it some of which are replacing all of the low voltage ceramic caps with film caps throughout, nicer electrolytic caps as the originals were getting quite old, I replaced the opamps with some AD825s and I have also replaced the differential pair with K170 JFETs. Oh and I replaced all the BJTs with lower voltage faster BJTs. I still have a few things to do to it but the sound is night and day compared to before. It wakes up the room. It is holographic, great imaging and much more detailed than before. The biggest difference came from switching out the BJTs with nicer units and putting the K170's in the differential pair (altering bias etc of coarse)
Everything is throughole on this DAC which makes it really easy to work with. The amps get switched out all of the time.
Everything is throughole on this DAC which makes it really easy to work with. The amps get switched out all of the time.
There's no need for a preamp if you don't have an analog source. I suggest a better DAC instead.
I'd like to read up more about gain and attenuation. More math, the better too. if anyone can post links, that would be greatly appreciated!
Pursuing the thread of trying out different DACs line driven into the X150.8, I took advantage of Amazon's Prime Day last week and picked up a Topping D70 Pro Octo. I'm now solidly in the camp that the X150.8 is the anchor (no pun intended), where it is highly resolving to upstream information. With the D90LE, there were huge gains in spatial resolution, and to some extent lower end into X150. The D70 seems to be resolving much more which includes the lower registers. Where extremely low frequency information on the D90 was a little diffuse and nondescript, the D70 hit the lower registers with much more definition/detail. Where I seem to really notice what the X150 is putting out in the low end is recording space ambience and size.
I have recordings (CDs) that now I'm hearing much more space (Cowboy Junkies - Trinity Sessions), and lower end resolution. After having my Zu Def III speakers (with built in sub array~12Hz) for over 12 years, I've never really heard the low end to this level. I'm actually understanding the speaker's full potential.
So this update was not as much around one DAC pitted against another, but more around the night/day differences the amp is opening up and passing down stream. It's been a long time but now I'm rifling through my CD collection.