Line Magnetic 219ia vs Mc225

Charles, i didn't feel you were being argumentative with anyone. All is good!

Excellent idea to go listen to these various LM amplifiers. Let us know your listening impressions. 
Charles 

I have the 219ia and the 518ia. They are great. Drive B&W, Sonus Faber and Harbeth with ease. Excellently well made. If they were made in the US you could triple the price and not blink.

I don't think I'm explaining myself correctly here. Aside from my comments about how to use comments and reviews, I'm not debating sound quality. That's beyond the scope of most of my comments. I'm saying that if you don't match your components properly, the system won't work. Good or bad sound is just irrelevant. You need a system that will work.

I asked why Shindo puts gain pots on their amps. The simple answer is, they need them. With high efficiency speakers, gain has to be considered at every level. Having the right amount of gain, for each of the components in the system, is critical for it to work. First, you need basic volume control. I'm sure we all understand that with a pair of really efficient speakers and a powerful amp, you can have a situation where the volume control is way too sensitive. Turn it just a little, and you get full volume.

You guys are not considering are all the amps in the system.   

" I listen at low to moderate levels generally. Even 2 watts will have the cornwalls blaring."

You're right, and that's where the problem lies. The speakers are so efficient, its easy to forget there is a power amp in your phono cartridge, phono preamp and line stage, aside from the one that actually drives the speakers. If your speakers only need 2 watts to get them going, its technically possible to drive them with a good line stage. In practical terms, this means your speakers are the equivalent of a powerful microscope. You will hear things with these speakers that you would not normally hear with less efficient designs. And what you end up hearing, besides music, is noise. If you don't have the gain set properly for each component, you can end up with a great deal of noise to go along with your music. It can be on a scale that makes your run of the mill ground hum, that would drive most people crazy, sound minor.

Someone above mentioned you need high quality, clean sounding equipment. Absolutely correct, but with high efficiency speakers, its not enough. As clean as the Shindo amps are, they still feel the need to put global gain settings on their amps. Without the ability to adjust gain for the amp itself, you can still have noise issues regardless of how expensive and well made the amp is. Same thing for your sources and line stages. For example, I have a very good CD player. It does come with its own volume control, but the main reason I bought it, is for the global gain settings aside from the volume control. Most of the time it gets used with speakers similar to what most people here are using (efficiency wise). I have a pair of speakers I sometimes use that are 94db. If I don't open up the CD player and lower the gain, you get a hiss so loud, you can't enjoy the system. But understand, this has nothing to do with how good the CD player is. It's a 10k Stereophile A+ unit. (If I remember correctly).

So, just as an example, I know I can take my CD player and a pair of Shindo amps, connect them to your new speakers, and get the system to work properly. Will the system sound good? Maybe, but we're not at that point yet. Please don't think I'm trying to start an argument here. I just have a little experience with some of the problems you can encounter with components like this. Not everyone has a CD player that has the type of adjustments mine has. This could be a real problem for someone in that the system just won't work. When I say you need to try the equipment first, it's not for the luxury of better sound, but just for basic functionality. 

[Edit: I composed the following before seeing mb1audio’s post just above].

Hmm. The comments by mb1audio prompted me to find this Stereophile review of the Line Magnetic LM-518ia. (I couldn’t find reviews of any of the other LM amplifiers that included measurements). With respect to that model, at least, a couple of things strike me as being significant concerns if the amp were to be paired with 102 db speakers:

1)The measured signal-to-noise numbers are definitely in the worrisome category, given that 102 db speakers will be used. I note that the reviewer used the amp with a number of different speakers, but I’m pretty certain that none of them are rated higher than 93 db. JA’s comment:

Switching an A-weighting filter into circuit improved these [signal-to-noise] ratios to, respectively, 65.6, 67.4, and 68.8dB, which will be barely adequate with high-sensitivity loudspeakers.... Repeating the spectral analysis with the volume control at its minimum setting didn’t lower the noise floor. This suggests that the noise occurs after the volume control, which means that, unlike other amplifiers, reducing the volume won’t improve the S/N ratio.

2)Another of JA’s comments:

The maximum voltage gain, measured into 8 ohms, varied with the output tap, but was appropriate for an integrated amplifier: 40.2dB (16 ohm tap), 38.6dB (8 ohm tap), and 36.5dB (4 ohm tap).

In most circumstances those numbers are indeed appropriate for an integrated amplifier, but are significantly higher than I would consider to be optimal for use in conjunction with a 102 db speaker. The result may very well be having to use the volume control on the amp, and/or the volume control on any source components that provide a volume control, at undesirably low settings.

Unfortunately detailed specifications or measurements don’t seem to be available for the other LM models that have been mentioned. But given the foregoing the comments by mb1audio raise some very valid concerns IMO. Hopefully reports of user experiences involving the other models and similarly efficient speakers can be found.

Regards,
-- Al