Analyzing a 'mod'.. or discrepancy.

Tubes Asylum

Questions about tubes and gear that glows. FAQ

Okkay, so yesterday I'm doing my yearly once-over on my gear, and I get into my ARC sp6a preamp. I've had this unit for almost a year, and am quite satisfied with the sound. I'm looking at the circuit board, and I see many coupling caps replaced with angela / scr metalized polyprops. No biggie, all values agree with the runes.
Then I get to the last tube on the linestage, the one leading out to the power amp. These output couping caps caught my eye because they're not Angela/SCR, they're 'Aeon' or something like that, and instead of the 15mfd specified in the runes, it's 5.6. Previous owner obviously performed a 'mod'.
My question: What would this do to the sound? Was this in a quest for 'more bass'? 'less bass?' I'm familiar with using coupling caps to 'tune' a stage's sound, but I've never dealt with cathode followers before. The cap in question is circled in red in the schematic snippet below. It comes out of the cathode follower's cathode and leads to the power amp output.
When I got this preamp, I had Klipsch SF-2. My first impression, vis a vis my Sansui CA2000 sand preamp was "this pre is a bit thin on bass". Then I got my Fortes, and I have tons of bass. (The SF-2, in all honesty is quite thin from the low midrange and down, which is why they're banished from my system.)
I'm ordering the correct values. I'm interested to hear the results of bringing it in line with the original designs. I'm just curious as to the asylum's thoughts on this pre-existing 'mod'.
Please pardon the bad image quality on the scan. The cap in question reads "C10 15" (mf) and then a voltage rating.

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The Cable Cooker

Topic - Analyzing a 'mod'.. or discrepancy. - thoriated_tiger 10:54:58 09/30/04 (5)

Not much of an impedance issue, just sound quality... - serus 20:05:07 09/30/04 (0)

Re: Analyzing a 'mod'.. or discrepancy. - Audiopro 11:39:47 09/30/04 (3)

After I replace these caps... - thoriated_tiger 11:50:16 09/30/04 (2)

Mostly... - Russ57 18:00:33 09/30/04 (1)

Not really stressing.. - thoriated_tiger 18:47:58 09/30/04 (0)

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