CAT phono versus SP-6A phono


Brad V & I did a “shoot-out” between my CAT SL1 Sig Mk 3 & his ARC SP-6A. Both are tube preamps but the CAT is a 1999 model whereas the SP-6A must be 30 yrs old (made during ARC hay-days of preamps, which I believe was between 1970 & 1980).

The shoot-out was a healthy competition with neither preamp trouncing the other rather each played to its own strong suit of sound. What was remarkable was that the SP-6A held its ground pretty (damn) well despite its age. It must be noted here that Brad V did send his SP-6 to Richard Gray (of Richard gray Power Supply Company) to have the unit brought up to spec. Additionally, Brad has put some brand new EI Elite 12AX7 tubes in the phono section. The circuit & power supply resistors & capacitors are all original. The SP-6A was set to its max. phono stage gain of 60dB. The CAT has a built-in & unchangeable 72dB of gain from phono in to preamp out.

The rest of the system was: Bellavista Sig. ‘table w/ OL Silver 250 & Goldring 1042 MM cart , Symphonic Line RG4 Mk3 power amps, B&W DM604S2 speakers, & TARA Labs speaker cables.

We used an Earl Klugh & Dire Straits LP for the test. What we found was the SP-6A has a sweeter mid-range that was more forgiving & had more bloom. The CAT on the other hand was more accurate in that it did not add any sweetness of its own to the sound & it (therefore) had less bloom. If the music is not recorded “sweetly” then the CAT let us know that. If the opposite of “sweet” could be called “dry” then in comparison the CAT was on the “dry” side. Since the SP-6A was more forgiving in the mids & highs, it had a tendency to roll-off the high freq. extremes. The opposite was true for the CAT – since it was more accurate, the high freq. extension was much better.

The bass on the SP-6A was flubbier than that from the CAT. The CAT had tighter & deeper bass than the SP-6A. It was able to grab the woofer driver by the b---- & command it much better than the SP-6A.

We did run a 3rd experiment where we connected the ‘table to the SP-6A phono stage & took the output from the ARC tape-loop & fed it into the CAT line stage. This seemed to give us the best of both worlds – lush mid-range, high freq. extension & great bass.

So, in conclusion, it came down to “what sort of sound do like?”. Accuracy or musicality. Atleast in these 2 designs if you chose “accuracy” then you unit called the music just like it was recorded – nothing added & nothing subtracted (atleast to both Brad’s & my ears). If you chose “musicality” then the unit added some forgiveness to the music, created a lush midrange & added some mid-range bloom, which probably didn’t exist in the original music/recording. This lushness was not overpowering or artificial but was easy to detect in comparison to the CAT’s sound.

Hopefully Brad V will jump in & add his comments as well.

It’s back to the much talked about choice - accuracy or musicality! Maybe there are preamps out there are both musical & accurate. Does anyone know about such preamps?
128x128bombaywalla
If you like the SP6 but want some of the benefits of the CAT try an ARC SP10II.
bombaywalla
I just left ozzy62 and EXCELLENT system there.His analog
sound GREAT
Hey Blcube,

Yes, I know Ozzy too + I have heard his system as well. Yes, it does sound excellent. Must be sounding much better these days after he put NOS tubes in his phono stage.

I have the exact same tonearm as he does!

You will have to agree that the OL Silver 250 sounds much better than the modified Rega tonearm you had on your Bluenote 2 yrs ago.

The Borghese must be very good as you say but I cannot believe that the OL Silver 250 is not as good.
Re. the ARC preamps - yes, I'm finding out that the SP-10 & SP-10 Mk2 were some of the finest ARC SP series preamps ever made.

Another data point from my perspective - I had the opportunity of hearing a ARC Ref 1 (connected to a Symphonic Line Kraft 250, Newform Research speakers, LP12, ARC PH-1 phono). That sound of that system did not impress me at all! It seemed like the sound was veiled & wanted to break free but somehow was trapped & couldn't! I felt that the SP-6A was much better. Quite remarkable since it cost much, much less than a Ref 1.

I understand that the Ref1 & Ref2 are hybrid tube designs like the SP-9. So much for hybrid designs if not executed just so!!

My speakers are a bit on the dark side so the accurate CAT preamp works great with them. My friend's are much more neutral & an ARC-type pre works great in his system. If I had the SP-6A in my system, it would be a bit to "syrupy" for me. I'll have to find someone w/ a SP-10 & compare that to my CAT.