Locutus,
Out of curiosity, what audio interface are you using? I am myself looking for an asio compatible sound card. I know you're not using it for that, but I thought I'd ask anyway. If you like the sound of its mic pre-amps, and if you can do 2-channel recording with decent condenser mics, that's better than any interface I've owned, since all I've used up to this point were dirt cheap ones that sometimes barely worked. Lol
Also I have a fair bit of information about a possible recorder option for you. Just a disclaimer, the below long post is not a sales pitch, though I am trying to be thorough so you'll know what you're getting into if you decide to follow in my footsteps. I'm just telling you my personal experiences, take them with a grain of salt.
I think either the Olympus Ls-100 or the Zoom H5 may be two good options to look at. I've not tried the LS-100, though I think it has what you're looking for, in addition to voice guidance. Its mics are also pretty good too, and from what I heard it has excellent mic pre-amps. I can't say whether it has XLR inputs but I think it does.
I purchased the Zoom H5 recently. It was not terribly cheap, I think I got it for around $350. However the reason I went for it was because I was coming from a Zoom H1 background. The H1 was a fine recorder, especially for its low price, but it was starting to fail. I still have it and use it, and if I make sure everything's working well beforehand, it normally does work. But I wanted more. I didn't want to get the H2, H4, etc. because they are a little older. The H5 is a 4-track recorder, with two tracks allocated to the internal mics and the other 2 tracks being used by 2 quarter-inch/combo XLR jacks. So, you could use your XLR mics with it with no issue. Because it can function as a 4-track recorder, you can also record with the internals simultaneously,which you said is something you want. The H6 from my understanding is the same as the H5 but is a 6-track unit, and they have an 8-track one as well, I think it's the F8.
So far I've only used the H5 for stereo recording, I've not yet set it in multitrack mode and tried anything with it. I think it gets a little complicated if you do that, but I anticipate that it would be workable.
The H5 menus are complicated but almost all of them are manageable, with the exception of a few such as the USB control and mixers. I've not yet figured those out, but they were not a priority with me when I got the unit, so I am not especially worried about them right now. But if you get almost any Zoom recorder, you will have to learn its menus. This is a deal-breaker for a number of blind people. I understand their frustrations, I have them too, but I don't like sticking to accessible recorders, because there are so few, and so far as I know, Olympus has pretty much taken over that market. I prefer the sound of zoom so that's what I went for. The hassle of going through menus was something I was willing to accept, but that'll be something you'll have to decide when you make your choice as to what to buy.
A word about the internal mics on the H5, H6, and I'm pretty sure the F8 as well. The internal mics can actually be removed and replaced. Zoom provides alternative mic capsules which you can purchase for different use cases. I'll briefly describe the capsules below. The H5 comes with the XY-H5 capsule, the H6 comes with the XY-H6 capsule, not sure about the F8. But all the capsules can be purchased separately, so if you get the H5 but later want the H6 mics on it, you can very easily do that. Removing and replacing the capsules is easy. From what I've been told it's kinda like how you would replace camera lens, but I've never done that so I can't compare.
Now for the capsules, just a brief summary of each.
Xy-H5 capsule comes with H5 recorder. It's an XY mic with a 90 degree field, and it also has a 3.5MM jack for plugging in external mics. It really shines with louder sounds, or at least it's supposed to. For quieter stuff it's a little noisy and the stereo image isn't terribly wide, but it's a good mic. Can't say anything about the price since I got it with my H5. It also came with a windscreen in the box, which in general all Zoom mics need a windscreen as they are cartioids.
Xy-H6 capsule comes with H6 recorder. It's an XY mic with a 90 degree field. However you can change that by twisting the capsules, I believe away from you, until they click stop. This expands the field to 120 degrees, which creates a wider stereo image which I rather like. and it also has a 3.5MM jack for plugging in external mics. It really shines with quieter sounds, I can say that with experience. Its noise floor is quite a bit lower than that of the XY-H5. Can't say anything about louder sounds as I haven't tested, but for your solo harpsichord and violin stuff, I'd absolutely recommend that capsule if you decide for some reason you only want to use internals. It's my favorite stereo mic so far for general recording. Price is $75 or so. I didn't receive a windscreen with mine so I'll have to order one.
SG-H6 is a shotgun mic that can be purchased. It only picks up sound directly aligned with it, so it's useful for recording isolated sounds in a more noisy environment such as birds outdoors or speakers at a conference. I don't have this one but I've heard it's not the best. It has some noise and from what I heard it's not a great shotgun because it is pretty small and thus can't isolate distant sounds well. Still it's an option if you're into that sort of thing and have the money to spend.
MS-H6 is a mid side mic that can be purchased. I don't want to go deeply into MS recording details (that can be explored elsewhere), but basically the mic allows you to record a center perspective and a side perspective, and then you can later mix them in post-production to tweak the stereo image. You can sort of do that with the XY mics with a channel mixing plug, but this one has a different pickup pattern which is more optimized for MS mixing I think. You can also adjust the center/side balance on the recorder from what I'm told, or you can just record in MS-Raw so that a dedicated MS plug-in in post-production can work with it. I don't have this one but I've heard it's not the best. It has a lot of noise in a lot of the recordings I heard, but the stereo image it can produce is staggering. Some of the stuff I heard took my breath away with just how much of the space I could perceive. If you are not recording quiet sounds, it would be more useful.
SS-H6 is a combination of the SG and the MS mics I mentioned above. Basically you have a shotgun picking up the middle and a normal MS configuration picking up the sides. What it is meant for is recording isolated sounds in the center with control of stereo ambiance. You likely wouldn't want to be doing field recording with this. For solo instruments it could be useful if you want a center-stage sort of perspective. You can also adjust the center/side balance on the recorder, or you can just record in MS-Raw so that a dedicated MS plug-in in post-production can work with it. For what it's made for, I think it could work well, but it's finicky. I can say this from experience. The image is either really focused, or it is so wide that there really is no definition and thus the perspective gets really blurry and unsettling. You have to know how to use it, which I don't quite know yet since I've never attempted this kind of recording before, and I've learnt most of what I know from experimentation. I think it is a decent capsule if you use it right and if you keep in mind that it's not a standard stereo mic that you can just sit anywhere and record indiscriminately. There weren't many samples of this that I could find, only maybe one or two, both of which weren't very revealing, so I bought this on a gamble. I like it but I'd caution anyone who's buying it to not expect anything concrete from the outset like I did. I think with this mic especially you have to experiment with it to know what you'll use it for to really get a feel of it. It does not come with a 3.5MM connector, so you can't connect external mics to the capsule itself, you only have the quarter inch/xlr combo jacks for mics at that point. I purchased this for a little under $150 I believe and it came with a windscreen which looks like a fox tail. In fact that's what my family and I jokingly call it. It's pretty effective though.
There's also another capsule that replaces the two internals with two XLR/quarter combos I think. That's pretty cool if you think you'll need it.
If you want to hear recordings or ask about anything I've said, feel free. If you do eventually decide to get the H5, I can help you with menus. I wrote up a menu tree that is almost complete, with the assistance of my mom. It covers most settings though there are some parts which we found confusing so I left those out.
Let us know what recorder you ultimately decide to get. good luck!
Make more of less, that way you won't make less of more!
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