Rickresource Rickenbacker Forum

Hi all,

I've been reading a lot about the .0047 cap bypass mod on certain basses, i.e., stock push/pull tone pot on later model 4003s and folks doing the bypass mod on C64s, etc. I know I have the cap in my 78 4001, but I was wondering if the following models had the cap as a stock item:

1) 60s 4001
2) 60s 4001S (i.e., McCartney's and Squire's basses)
3) 4001 V63

My sense is that McCartney's had the cap as did Squire's (horseshoe issues on those two basses notwithstanding) but was also curious about the other models.

Thanks!

1 and 2 have the cap, 3 does not.

Thanks for the quick response Jeff. Interesting that they left the cap out of the V63 since it was intended to emulate the 4001S. Wonder what the thinking was there. Nevertheless, I'm about to pull the trigger on a C64 MG and will have the cap bypass mod put on it so I can have the best of both worlds. Can't wait!

SMR 78 wrote:Thanks for the quick response Jeff. Interesting that they left the cap out of the V63 since it was intended to emulate the 4001S. Wonder what the thinking was there.

JH has said that the cap was in the circuit because amp/speaker technology way back when (1960's) was not what it is today. In order for a capped bass to sound like it was intended to, one would need an antique amplifier.

Following that same line of reasoning...Now that amp/speaker technology has been upgraded, RIC not installing a .0047 cap would make the V63 (or the 4003) run through a modern amp sound similar to an RM 1999 run through an antique amp.

Why RIC put the cap back in the C64 is the question! And I guess the answer is because the C64 was intended to be a more accurate reproduction than the V63.

SMR 78 wrote: Nevertheless, I'm about to pull the trigger on a C64 MG and will have the cap bypass mod put on it so I can have the best of both worlds. Can't wait!

Congrats in advance when you get it!

My $.02: Don't bother with the push/pull. Bypass the cap and don't look back!

Interesting. I'd heard the thing about amps "of the day" not being able to handle the signal right with all the low freq's, so the cap was there to cut them. But, I'd never equated that to mean that with the cap, the old amps would sound like a modern amp and no cap in the bass (or vice-versa)...

Yeah. I still don't get that, either.

Hard to say without doing a comparison. Anybody got an RM1999 and an antique amp?

I'm actually glad they put the cap in the C64 - Squire and McCartney had the cap at least until whenever their horseshoes went out, so I'm looking forward to dialing in some of their sounds as best I can with the cap and the toaster / horseshoe combo. I say some, since to me Macca sounds capped on Sgt Pepper and MMT but toaster for certain White Album and Abbey Road tunes and Wings up to '75 when he got the high gain in the bridge. Squire always sounds capped to me (i.e., he's bringing in the horseshoe). But I've read so many ringing endorsements of the tone of the horseshoe without the cap that I definitely wanted to have that option.

Now to wait for delivery day

cjj wrote:Interesting. I'd heard the thing about amps "of the day" not being able to handle the signal right with all the low freq's, so the cap was there to cut them. But, I'd never equated that to mean that with the cap, the old amps would sound like a modern amp and no cap in the bass (or vice-versa)...

I don't think it was so much to cut the low frequencies that the amp couldn't handle, it was to help the clear up higher frequencies that the older bass amps had a hard time producing.
If it were to cut low frequencies that the amps couldn't handle, the cap would have been on the bass (neck) pickup.

I´d support that. Remember that the 4000 didn´t have the cap - and the amplifiers used would have been about the same. The way I understand it is that the cap brightens the sound of the horseshoe while still allowing bass added to the sound via the neck toaster.

I absolutely love the tone of my '71 with the toaster and capped bridge pu combo!

Yeah, I have to say, I like the tone with the cap, both on my '76 4001 and '84 4003, of course, I'm used to that sound since I've never had a Rick bass without the cap until my 4004. I'm going to have to try those with the cap bypassed just to see how it sounds. I wouldn't mind adding a selective bypass, but I'm a bit hesitant to modify those two, especially the 4003 since it's pretty much mint and kind of a unique one. Somehow pulling the original pots and adding a new one with the switch just doesn't seem right. I'll have to think of a way I can keep 'em pretty much original but add a switch to bypass the cap...

cjj wrote:Yeah, I have to say, I like the tone with the cap...

<snip>

Somehow pulling the original pots and adding a new one with the switch just doesn't seem right. I'll have to think of a way I can keep 'em pretty much original but add a switch to bypass the cap...

+100!

I'd like to leave the pots untouched on my bass, as well, as in how they left the factory. However, I don't know of a way to short the cap without *some* kind of mod that's going to manifest itself on the bass's exterior (e.g., a toggle switch).

I think I've got a nice way to do it. I'm kind of busy with other things right now, but when I get it done, it'll be pretty cool. Not mess up the exterior and not change any pots. Probably even less obtrusive than my mods to turn my 4004 into the 4004Cjj...

Cool, looking forward to it.

The only thing I could think of in the past would be to replace the stock mono 1/4" jack with a 1/4" Switchcraft switching/transfer jack. That, used in conjunction with either a cable having a TRS or TS plug, would allow the cap to be bypassed or not. But I never sat down and figured out if it would/could work...

Before the pot/switch arrival, what people did was use a mini toggle switch in the bridge pickup cavity and dress the wires to the .0047uF cap. You reach into the cavity and flip the switch. Unobtrusive and other than a couple solder blobs on the cap leads, original.