ARC SP10. That’s a pretty old preamp, back in the days when a lot of tube preamps had that big tube bloom and coloration. Problem was, in most cases, they had that rich sound but not very revealing, things get lost, slow and the bottom end although fat was not as controlled as modern tube preamps. Local shop just took a SP10 in on trade and sent it back to ARC to go through. I had quick listen and pretty much what I remember about old ARC preamps. If you want that kind of sound but much better I’d look for a ARC LS5 MK III. It’s fully balanced and only balanced out so you’ll need an amp with XLR inputs. That was a great preamp in its day.
Today most tube preamps, including ARC, are a lot more neutral such as your MW LS100 which I’ve not heard but I suspect it falls somewhere between the SWL 9.0 SE and LS36.5 which I’ve owned both and still the later. If you’re by chance using the stock power cord I’d strongly suggest replacing that. When I bought my LS36.5, Dan Wright suggested I get a WyWires PC which I did and it really opened up this fine preamp. Before you chase your tail on buying a different preamp I’d look at the power cord and also the Daedalus isolation devices, three, underneath your LS100 will probably amaze you. Dan sells the DID’s and being a MW owner, he’ll likely give you a decent discount.
The order I would suggest first is the DID’s, power cord then fuse. Yes I did the fuse in my LS36.5 and it dropped the noise floor a little and opened things up. I use a NOS rectifier tube and cryo 6H30’s with Herbie tube dampers. Just bringing this up if you’re hard set to upgrade, the MW LS36.5 is fine preamp.
The latest version of ARC preamps I’ve had in my system was a LS 25 MK II and I preferred the MW SWL 9.0 SE. By comparison, I found the LS 25 leaner and had little to no PRaT that the MW has. The LS36.5 is at another level of the two by a considerable margin.
I’m sure the other preamps you mentioned are wonderful as they get plenty of good press, and so does your LS100. I’d look at my suggestions as it will probably be less money in the end and I bet it will bring out how great your current preamp truly is.
Today most tube preamps, including ARC, are a lot more neutral such as your MW LS100 which I’ve not heard but I suspect it falls somewhere between the SWL 9.0 SE and LS36.5 which I’ve owned both and still the later. If you’re by chance using the stock power cord I’d strongly suggest replacing that. When I bought my LS36.5, Dan Wright suggested I get a WyWires PC which I did and it really opened up this fine preamp. Before you chase your tail on buying a different preamp I’d look at the power cord and also the Daedalus isolation devices, three, underneath your LS100 will probably amaze you. Dan sells the DID’s and being a MW owner, he’ll likely give you a decent discount.
The order I would suggest first is the DID’s, power cord then fuse. Yes I did the fuse in my LS36.5 and it dropped the noise floor a little and opened things up. I use a NOS rectifier tube and cryo 6H30’s with Herbie tube dampers. Just bringing this up if you’re hard set to upgrade, the MW LS36.5 is fine preamp.
The latest version of ARC preamps I’ve had in my system was a LS 25 MK II and I preferred the MW SWL 9.0 SE. By comparison, I found the LS 25 leaner and had little to no PRaT that the MW has. The LS36.5 is at another level of the two by a considerable margin.
I’m sure the other preamps you mentioned are wonderful as they get plenty of good press, and so does your LS100. I’d look at my suggestions as it will probably be less money in the end and I bet it will bring out how great your current preamp truly is.