Buy an Audio Research SP10 MkII or an SP11 MkII ?


Help

I love that big image, valvey pre-amp sound but I don't know which pre-amp to choose ... an SP10 or SP11..... Quandry ! What do you think ... or should I be looking for something else .... help.

I have ...
Audio Research D115 MkII *2
Kinergetics SW800
CAL Tempest MkII
Oxford Crystal Reference Turntable with Airtangent and Koestsu Rosewood Signature

Have fun
growlar

Showing 4 responses by jafox

Another vote for the SP-10 if you are dead set on this or the SP-11. I owned the SP-10 for 8 years and loved it, even with its rolled-off frequency extremes, rather high noise floor, and yes, constant replacement of the phono-stage tubes. But oh man, the midrange bloom and dynamic contrasts to die for at the time. The ultra-low noise RAM 6DJ8 tubes worked beautifully in the 80s.

When ARC returned to all-tubed preamps in the early-mid 90s, the LS5, one listen to this with the companion solid-state PH2 and my SP-10 was for sale.

If you want what the SP-10 offers, I suggest you use the same $2500-3000 or so and listen to an LS5 II or III and keep your eyes out for the matching PH2 on the used market. This combination has ALL (yes, all) the strengths of the SP-10 but has refinements across the board. The SP-10 really is only good for phono playback as its line stage is mediocre at best. I realized how true this was when the LS5 destroyed the SP-10 for line level sources. So if CD playback is also a big part of your listening session, I would consider other options.

Concerning the SP-10's claimed gain of 72db, I would be skeptical of this claim relative to newer products. What good is the gain if there is so much more noise in the background. The LS5 II has 30db and the PH2 48db for a total of 78db and this combination had far more gain and S/N than the SP-10 when I made the change. The SP-10 just barely worked with cartridges at 1mv so I stayed with such models: Sumiko Virtuoso and Shinon Red in the 80s and early 90s. The Benz Glider of today would be a comparable output cartridge.

When I upgraded to the Koetsu Rosewood Signature 2 years ago, the LS5/PH2 combination was not enough to handle this so I changed to the BAT VK-P10 and then Aesthetix Io phono stages which have upwards of 70db each! But I ran each of these at 54 db - the extra 6db over the PH2 was what I needed. There is no way the 0.6 mv Koetsu will work well with the SP-10 unless you have found miracle tubes and the unit has gone through a major upgrade of parts.

John
Holy cow, I never could have had success with a 0.2mv cartridge with my SP-10. Mine was an unmodified MK II, and like I mentioned above, used RAM tubes. Perhaps the Sovteks or other available tubes of today are quieter which allows for higher gain. But still, the SP-10 was simply too noisy for me after I switched to the LS5/PH2. And, I kept the low noise RAM tubes when I sold the SP-10 and used them in the LS5 which worked mighty well. But again, they were not used in a highly critical phono stage. So it could indeed come down to quieter tubes of today.

Yes, the SP-10 was an outstanding product, but much has happened in the 20 years since then and to spend $2500-3000 here, unless you are a collector, just makes little sense.

John
Rcprince: Yes, with the LS5 being truly balanced XLR ins/outs only, this does have the potential to change things for someone whose system is all RCA connections. At the beginning, I used adaptors for my single-ended CD player and tuner. The '-' phase input is simply grounded so only the '+' is used and this worked mighty fine. Just about any amp these days has balanced inputs. And whatever you do, stay away from those BL1,2,3 conversion boxes. The extra stages and interconnects do far more harm than the benefit of converting single-end/balanced.

Growlar: The Mk I had 2 types of tubes for the 10 total. This was at the time when a shortage of 6922 was thought to become a reality. The II switched to 10 6922's when these tubes, Sovteks, were suddenly plentiful from the former USSR. There was a claimed reduction in noise. Both of these models had a switchable 30db/12db gain. But I always ran my II at 30db as the 12db setting had a reduction in 3-dimensionality.

The MK III took the audio circuit from the Ref 1 and amazingly retained all of the II's sonics. How they did this was beyond me, but it was far more neutral on the top. The I/II had a little excessive sibilance in the upper freqs that can be a bit annoying once you hear the III seconds later. But the II has a little more bass weight and authority. The III's strength of more natural tonal balance and its higher resolution, especially in the mids, won me over after owning the II for 7 years. The III typically was factory set as 12db, but a change of 8 resistors takes it up to 18db. I changed mine to 18db and this worked much better for phono sources. And ARC claimed the noise level to be a little lower with the 18db.

As for the holographics of the SP-10, oh man yes, the LS5 in any version has this in spades. Without it, I would have abandoned ARC as none of their other products had this. The LS2/15/22 all failed miserably in this area. If you're a fanatic of harmonic richness, 3-dimensionality, long decay of notes, for the money, the LS5 is unbeatable.

As for a phono stage, it's pretty tough to find one that has the same magnitude of strength in terms of bloom and decay unless you start to get serious at expense. I have an Aesthetix Io and this with Telefunken tubes brings on a level of decay and 3-dimensionality that simply was far ahead of the solid state ARC PH2 and tube BAT VK-P10 phono stages I had before.

I wish there were a way for you to hear the SP-10 vs the LS5 for line sources so you could hear for yourself how dated the SP-10 is here. For me the LS5/PH2 really did it all that the SP-10 did. I was not wanting for more bloom with this pair following my 8 years with the SP-10. But something like the LS5/Io or even more so, my current BAT 31SE/Io destroys the LS5/PH2 in the magic. But now we are way beyond your budget.

I have heard that people use the SP-10 for its phono stage only, using the tape out lines to drive a line stage. That could be an ultimate option for you by starting out with the SP-10. But still, you have to keep the line stage tubes in the SP-10 to keep its power supply stable.

Ultimately, if you want that tube phono magic, and in the line stage as well, it's going to cost you no matter what. Just try and listen to these products, next to each other in the same system so you can hear for yourself their strengths/weaknesses.

One final thing to remember, just because a unit has tubes does not guarantee anything that you will get the tube magic warmth, bloom, decay, etc. You have to listen to hear it for yourself.

Sorry for rambling so darn much.

John
Growlar: I like your idea of the evolution process. You will indeed enjoy the heck out of the SP-10. And then some day if you have the itch, persue that next level of refinements. But I guarantee you that so many newer products that you will audition will not make you dance and smile like the SP-10 causes you to do. Half the fun is discovering such a special product. So just go for it!
John