Review and Measurements of Lounge LCR MKIII Phono Amp

[Lounge Audio]

In that case, I'd take seriously the results of independent testing and use it to improve the product. Amir has given you for free what a consultant would have charged you thousands for. Don't "defend" the product, evolve it.

What makes you think I don’t? Did you not see my FR test? What do I do with his sweep if those bumps don’t show up for me? Hmm evolution? Since 2011 there has been mk1 2 and 3, Gold, Silver, Max and Tube. From no trim pots to trim pots for both highs and lows. How much more evolving do you want? Since when did a consultant post problematic results on a public forum?

 

[SIY]

Many possible explanations. Perhaps a variation from unit to unit? Perhaps variability or calibration in your rather old test gear? Perhaps variability from other sources (e.g., frequency settings- I noticed in your YouTube videos that when you'd call out a frequency, the dial on the signal generator was set to a somewhat different place)?

If I were you, I'd investigate why that's happening, and certainly invest in some more modern test gear. AP is, of course, the gold standard, but for your purposes, you can get something which will serve your needs for considerably less.

 

[Lounge Audio]

Many possible explanations. Perhaps a variation from unit to unit? Perhaps variability or calibration in your rather old test gear? Perhaps variability from other sources (e.g., frequency settings- I noticed in your YouTube videos that when you'd call out a frequency, the dial on the signal generator was set to a somewhat different place)?

If I were you, I'd investigate why that's happening, and certainly invest in some more modern test gear. AP is, of course, the gold standard, but for your purposes, you can get something which will serve your needs for considerably less.

I can get to an AP soon enough and the units have been tested before that way. I have analog means to do a pretty good job myself. I’m going to state again that results such as have been posted here do not represent what I have seen over the years with my spot checks. Just for example the FR test I show is being calibrated with a frequency counter, increase you didn’t notice. For a third time, my offer is still up to have the owner to send me the unit.

 

[SIY]

And my offer still stands to get a unit to do comprehensive testing in a way that you and Amir don't.

 

[Lounge Audio]

And my offer still stands to get a unit to do comprehensive testing in a way that you and Amir don't.

Thank you. Maybe you missed in a prior post here that I am already consulting with an engineer that retired from Jensen transformers. I have been a member of the Hollywood Sapphire Group for 18 years. Plenty of members there will, and have let me use their gear to check things and get consultations. Go to www.hollywoodsapphiregroup.com and see the list of names that are basically at my disposal.

 

[SIY]

Then I certainly hope you use those resources to fix the design and consistency issues that have come to light here.

 

[Lounge Audio]

Then I certainly hope you use those resources to fix the design and consistency issues that have come to light here.

I will. However you are operating under the assumption that the anomalies shown in the tests performed here are representative of a global failure. As you probably know, a sample of one can’t be used to conclude that a discrepancy is a global one. Hence, that is why I persist on asking to get this unit to evaluate.

 

[SIY]

I will. However you are operating under the assumption that the anomalies shown in the tests performed here are representative of a global failure.

I'd use the word "inconsistency." I know of two people with 21st century measurement capabilities (and the smarts to use them properly) who have tested these boxes and both have reported pretty severe frequency response errors. As well, the anecdotal descriptions are all over the place regarding tonality- that may be because of the inherent unreliability of anecdotal reports, it may be because of widespread inconsistency, it may be some of both.

On a positive note, I congratulate you for not slapping a silly price tag on this. $300 is a very reasonable deal, especially if the potential issues of consistency can be rectified.

 

[patient_ot]

Is this starting to remind anyone else of the Schiit Yggdrasil DAC testing? IIRC results were in dispute so a second device was tested - outcome was similar. Maybe Amir ought to test another Lounge unit to be sure?

 

[Lounge Audio]

I'd use the word "inconsistency." I know of two people with 21st century measurement capabilities (and the smarts to use them properly) who have tested these boxes and both have reported pretty severe frequency response errors. As well, the anecdotal descriptions are all over the place regarding tonality- that may be because of the inherent unreliability of anecdotal reports, it may be because of widespread inconsistency, it may be some of both.

On a positive note, I congratulate you for not slapping a silly price tag on this. $300 is a very reasonable deal, especially if the potential issues of consistency can be rectified.

The two units you are referring with the inconsistencies (I assume these are two units that are not part of the DUT used on this thread) are proof to you but until I am able to evaluate them they are anecdotal to me. Don’t get me wrong, I’m not saying there can’t be inconsistencies here that deserve attention on my part. At this point, until this thread, I have never had a complaint about RIAA compliance. Whenever I am contacted by owners (notice I say “owners” not “customers”; because there have been people that purchased units secondhand and I treat them as though they purchased directly from me) I have done all that I can do to rectify their problems. This has extended to me making cables and power line filters at cost or for free to isolate system problems that the owner has tagged my product as being the source.

Thanks for mentioning the fact that I keep my prices under control. This is in spite of the units being wholly manufactured at my shop from blank PCB on up. We here at Lounge feel very fortunate to have a steady stream of orders coming from dedicated vinyl listeners no less!

 

[SIY]

I didn't use the word "proof," you did. Certainly suggestive- if you have independent measurements using 21st century test gear to the contrary, we'd all be interested in knowing about it. I'd also be interested in quality measurements of EQ versus level, which can be a weak point in inductor-based EQ.

In the meantime, if you or anyone else wants to send me one for a comprehensive set of measurements (Amir and I disagree on what's necessary, but my way is certainly more intensive and takes the cartridge into account), I'm ready and willing.

 

[dinglehoser]

@SIY @amirm @Lounge Audio

I'm the owner of the unit in question. I'm happy to send this thing on whatever journey the three you of you see fit, because, you know, science! (Also, that's one less thing I'll have to move!)

 

[SIY]

I'm sure Robert will want it directly, but if possible, I'd like to have a crack at it first to verify Amir's measurements and add a few of my own, then I'll send it on to him.

If that's OK with you, please send me a PM.

 

[dinglehoser]

My suggestion would be for Amir to first send to SIY, so he can run his characterization on the same unit. Then, SIY could send to Lounge for evaluation/confirmation. If Lounge then also decides to tweak the unit, I ask that there be an audit trail of all changes/adjustments made, then the unit can make its rounds with Amir and SIY again.

I love this forum for its rigor - this debate is no exception! Thank you, all.

 

[dinglehoser]

Additional context for the unit in question: I bought it directly from Lounge in October 2016. It's always been paired with a VPI Scout Jr. with an Ortofon 2M Red cartridge, with short (3') Blue Jeans LC1 interconnects (see here for tech specs: https://www.bluejeanscable.com/store/subwoofer/LC1-design-notes.htm). Aside from some persistent audible hum, I've had no functional issues with the device. I'll withhold my public comments re: subjective opinion.

 

[amirm]

I took measurements at the two points your FR graph deviates the most for in-band audio.

Hmmm. Is this what a production unit looks like?

And what is the signal generator? You only show a scope, the meter and frequency counter.

 

[amirm]

Me
" Start playing different material through your system. I think you will notice that you hear more differences in pressing/mastering quality than before. Also with less smearing you can turn up the level more without things getting shouty or congested. The smearing I am referring to comes from many technical aspects in phono preamp designs. In my experience two big culprits that cause smearing are surface mount components and active feedback RIAA topology. For the surfacemount components (called SMD) the capacitors made this way are almost always trading compact size for performance. As for the feedback RIAA the time delay of the high frequencies feeding back through usually a consumer grade op-amp will cause some ringing that smears the high frequencies. What this does for your listening experience is make the phono preamp have a static sameness to the high frequency response."

Seems like you bamboozled him with technical jargon. Such tactic doesn't work here.

How exactly did you determine SMD parts cause smearing? Who says you have to use all SMD parts in a design? You can just as well use a through-hole capacitor if you feel that is a big deal.

SMD designs shorten paths which is greatly helpful in analog designs. We have DACs and headphone amplifiers which achieve 50-70 dB better performance than your design. And both have raving reviews from customers as well.

As to feedback and ringing, that only happens with illegal audio signals like square waves with very fast rise times. You have one of those coming from an LP? If so, let's see a measurement graph of such.

Until then, these are the voodoo arguments that I was talking about. You don't do SMD design and manufacturing so it must be a bad thing. You don't understand the nature of feedback so that becomes a bad thing too. You throw out star-trek language at lay customers who can't counter. Please don't use them against us. It only deteriots your position here.

 

[amirm]

Thread starter again
"Doing more deep listening. I ditched the platter mat, and that actually tightened up the sound a bit more.
What's weird/cool is that I've never been able to hear these kinds of differences before I embarked on my massive upgrade campaign...it's a blessing and a curse. Mostly a blessing.

"

Sadly this had nothing to do with your product or said mat but how our brain functions. We make a change, the focus on the sound and hear detail that was always there but not captured by our brain. It is like looking down in the dirt and finding a coin in there when you go digging. You wouldn't see it otherwise because you weren't digging!

 

[SIY]

And what is the signal generator? You only show a scope, the meter and frequency counter.

In the YouTube video, you can see that it's an old Leader signal generator.

 

[patient_ot]

Here are some claims I often see thrown out by manufacturers and vinylphiles alike:

Passive RIAA is better than active RIAA equalization.

Surface mount components are bad.

"Discrete" designs are better than anything that uses op-amps.

Tubes sound more "natural" than solid state phono preamps.

Point to point wiring with tube components is best, rather than a PCB design.

Negative feedback of any sort is bad, non-negative feedback designs are superior.

SUTs are better than "MC head amps" for LOMC cartridges.