Monoprice Monolith Liquid Platinum Headphone Amplifier by Alex Cavalli

I’m finding the Amperex PQ’s brilliant with my LP with both the Abyss 1266 and ZMF Blackwood Autuers. Great tone, pace, dynamics, and headstage are all excellent. Though now I’m strongly considering putting my Abyss up for sale and picking up a GOTL.

 

Viva tubes on eBay store $64.57 shipped for gold lions use POPUPSAVINGS 15% off

https://www.ebay.com/itm/Brand-New-...n-Lion-Reissue-6922-E88CC-Tubes-/122620297209

 

A better place for this post would be
Deals thread or used deals thread

 

My bad, posted in deals thread, please delete these

 

Well, dealing with Monoprice's eBay support has been pretty much worthless, but I just returned the whole LP and should be getting a replacement shortly (all this to get a matching set of tubes...). Some preliminary thoughts on the LP with (non matching) EH's and 1960s NOS Amperex PQs with HE500s (w/balanced cable) and Modi Multibit:

On sound:
Resolution, clarity and head-stage are all incredible compared to the Lyr 1. I didn't know the HE500s were capable of this kind of detail retrieval, I can easily pick out every sound in a mix and trace it back to a nice black background. Extension is much better on both ends of the spectrum. The Lyr with the Amperex PQs in comparison gives a forward, relatively clear but full midrange but above and below the midrange there a lot of mud (no detail, separation or black background). On the flip side, I'm on the fence about the tonality of the LP with HE500s. My biggest issue is a hardness in the lower trouble that quickly becomes fatiguing with both sets of tubes I tried. I think the HE500s themselves are probably at the root of this, but I never noticed it with the Lyr. The Lyr (with PQs) was NEVER fatiguing. Because of this I often find myself reaching to turn down the volume on the LP. While the Lyr/HE500 combo is all about the midrange, the LP puts more highlight on treble. I would describe the overall tonality of the LP/HE500 combo as clear, dry and a little flat with a slightly accentuated treble. Someone in this thread used the word "plasticky", and while I wouldn't have chosen that word myself, I wouldn't argue with it either.

On tubes:
Compared to the Lyr 1, Im finding the LP is significantly less tube dependent. I tried the Lyr 1 with three different sets of tubes and each gave a very different overall sound. I wasn't happy with the Lyr/HE500 combo until I tried it with NOS Amperex PQs. I ended up liking those so much I lived with that combo for several years. Well, those "magical" Amperex's didn't do a whole lot in the LP IMO. It sounded different but not drastically so. I didn't get any of the warm euphonic midrange I got with these tubes in the Lyr. So far Im actually preferring the stock EHs, they had tighter bass, better dynamics and seemed more balanced overall.

On gain:
The gain on the LP is almost an issue with my HE500s. For me I start to get useable volume and channel balance between 8 and 9 o'clock on the volume knob. Im doing most of my listening between 9 and 10 o'lock which means there isn't any extra leeway. With anything more efficient than HE500s I think it could be a be a real problem.

So far Im loving the technicalities of the LP, but it seems to be missing something in terms of musicality with HE500s. To me, the overall tone is dry, vocals sound a little recessed and flat and the lower treble is hard and sometimes fatiguing. After getting used to the LP, the Lyr sounds muddy and is missing so much clarity/separation/resolution that it would probably be hard to go back to. Yet, I still love the full sounding, somehow simultaneously lifelike and lush midrange it provides. Its a unique sound that doesn't even pretend to be "accurate" but I find it quite enjoyable. Im hoping I'll come around to the LP with time (and matching tubes). I'll update once I have more time on it.

 

Thanks for the thoughtful write-up. Sorry the tube mis-match became such a hassle for you.

I agree regarding detail retrieval. One concern I had about LP vs my SS amp (Bryston BHA-1) was that I might lose detail. Definitely not the case, even/especially with Utopia. So far I like my Gold Lions best (vs. stock) with Utopia and Auteur. Amusingly, I have constantly fought the 'fatiguing' battle with Utopia (changed SS amps, went to R2R DAC, various cables). No fatigue at all with LP/Gold Lions/Utopia. I guess it's 'your ears, my ears'. I actually wonder if I would enjoy the T1g2 with LP. I owned them, but sold them quickly once I found that their sound hurt my ears after about 20 minutes.

Interesting...I just received some NOS Amperex PQs. While I wouldn't call the mids 'lush', I find the overall tonality of these tubes quite satisfying, and I love them with my Ether 2. It's the first time I've heard the headstage of E2 be really great -- open/spacious/airy/resolved. I had been 'meh' about the Ether 2/LP combo with both stock EH tubes and Gold Lions while LP/Gold LIons with Utopia & Auteur immediately sounded amazing. As far as 'tube dependency'... this is my first tube amp, so I can't express an opinion. I did note a significant difference going from stock EH tubes to Gold Lions with Utopia/Auteur. At the same time, very little difference between stock & GLs with E2, but much more when moving to Amperex PQ.

I'm in the same range as you (8:00 - 9:00, so actually a bit lower) with Utopia, which are very sensitive/efficient. No channel imbalance at useable volume. I wonder if it's just variation between pots and I got the unicorn? Different output voltage from our DACs? Something else which hasn't occurred to me?

 

@lcmusiclover Regarding tubes, mine are early 60s USA PQs, I don't know but there may be a lot of variation in sound between different PQs? There was definitely an immediately noticeable difference in sound between the PQs and EH, but it wasn't the game changing experience I had with the Lyr. With the Lyr it literally sounded like a different (and much better) amp when I installed those tubes, whereas the LP it sounded more similar than different (it still sounded like a LP). The PQs also seemed to highlight the hard treble issue I was experiencing with my HE500s, which was unexpected since they are so smooth in the Lyr. Maybe I should give the GL's a shot.

About the gain, now that you mention it it's not so much channel imbalance that's the issue, it's more that I don't get usable volume until between 8 and 9 o'clock at which point it starts ramping up quickly and by 10 o'clock its too loud. I think I generally listen at pretty average SPLs, Id guess mid 80s DBs, probably a little lower with the LP since the treble is limiting how loud I can listen without fatigue.

 

Yep, I barely nudge my volume to go from quiet to LOUD with Utopia. More range with all my other cans (EFO, E2, HEKv2, Auteur). I have a preamp (Emotiva XSP-1), but I'm shopping for a passive preamp, since I like the sound of my system without the Emotiva -- hoping a passive will give me volume control & source selection without coloring the sound as much (at all?)

I heard a (to me) big jump when I went from stock EH tubes to Gold Lions.

My PQs are 'Made in Hungary'. I'm a total tube-newbie btw.

As far as the Gold Lions, I found they did a lot for my dynamics, but didn't wow me with my planars. Don't know if it has anything to do with driver type, or if it's just a coincidence that all my dynamics are brighter.

 

I'm using stock tubes with HD650 and when the volume is at listening level there is channel imbalance. I have to turn it up a bit too loud to have channel balance. Is there some way to reduce the gain without lowering the computer digital volume?

 

Wow even with 300 ohms there is too much gain on this thing?!

 

Apparently the #1 problem with the LP. The original description indicated that there would be switchable gain, but that didn't make it into the final product.

Solution is a passive volume attenuator or a preamp.

 

Monoprice just increased price of this amp by 15%. Now ~$800.

 

What a load of shit

 

$770 at Monoprice's website. Probably there was a lot of interest in this amp, and they think the price increase is justifiable.

https://www.monoprice.com/product?p_id=33305

 

More than likely the increase in price was due to import tariffs from China. Expect to see similar increases on all kinds of electronics.

 

Up to $795 on eBay — $5 more than amp + shipping from website.

 

I'm using and can easily recommend the goldpoint SA1X as a passive pre-amp. It's completely transparent sound wise, only downside is cost (was also considering the Axiom II which is a bit cheaper, not sure if anyone else has experience with it). Having a usable volume knob though is night and day, definitely a design oversight for the amp. Even with my 600 ohm T1's the volume becomes un-listenable past 10 o'clock (and my LP has a channel imbalance under 8).

If you're a T1 owner you should take a hard look at the LP, as it has transformed my T1's (late first gen). This is probably due in part to modding them to be balanced (which is dead simple to do with the stock cable). The sound stage, imaging and tonality all saw noticeable improvements vs the Valhalla 2.

Tube wise I'm using Phillips Miniwatt SQ's. To be honest I didn't fully burn in the stock tubes so it's hard to do a direct comparison, but the most obvious change was an improvement in clarity with the Miniwatts. @nickwin I also received a pair of mismatched stock EH tubes, we should have just swapped so we both had a matching pair . I was more amused then anything else as I don't plan to use them in the LP, although there was no discernible channel imbalance so maybe they're at least measuring them. Might throw them in the Valhalla and use it at work.

 

Interesting. I’ve actually been thinking about the T1g2 (which I dropped like a hot potato soon after I acquired them). Given how I love LP/Gold Lions/Utopia together, I suspect LP w/ the right tubes might really help the T1.

On the other hand, I’m not sure T1 can do anything Utopia doesn’t do better.

Different topic: glad to hear Goldpoint is working for you. No remote though? I’ve been looking at the Hattor Mini:

http://mockingbirddistribution.com/hattor-audio/mini-passive-active-pre/

Allows 3 sources and 2 outputs w/ remote.

 

I don't know if I'd recommend going out and buying a T1 vs any of the newer TOTL headphones, but if you happen to have one on hand then the LP will likely convince you to add it back to your regular listening rotation. This was the case with me, I actually picked up the LP to use with the new ZMF Verite and the fact that it improved the T1 to the level it did was just a happy accident. I will say though that my T1 will now be seeing a lot more usage (before it was approx. 95% He-6 / 5% T1). Note I can only speak to the 1st gen T1, I'd be curious to hear though if the 2nd gen also sees a similar improvement.

New topic: No remote, to be honest I just set the SA1X to 13 on the dial and forgot it exists, no real need to adjust it. I have a bit of an custom setup though as I'm using a 150 watt power amp with my He-6's, so I run a separate SA1X into the power amp for safety purposes (which has been modded to reduce the gain a bit). I'm using a ISO Selector SoftSwitch (http://www.arx.com.au/worldwide/audibox-iso-selector.htm) to switch between the two SA1X pre-amps (with gungnir multi as a source). This way the volume knob of the SA1X -> power amp can always start at zero and I avoid accidentally blowing up the He-6s (which seems a fair trade-off vs the extra cabling). The Hattor looks like a solid option, but unfortunately I have no experience with it.

Edited to add: The T1 will likely never be bested when it comes to bright treble .

 

Yes, the word ‘trepaning’ frequently occurs in T1 impressions