Reissue Dearmond RC1100 demo

**Para** · 08-01-2015, 05:39 AM

Hmm you really don't want overtones.

**nopedals** · 08-01-2015, 06:02 AM

Anybody have a schematic for the volume and tone box? I am assuming the RIs don't come with a box or schematic, correct? And that would be part of the sound of the originals. There used to be a schematic for the old box on the web. As noted above, running down 250k thumbwheels may be a challenge as well.

**Cunamara** · 08-01-2015, 09:11 PM

Scuffling around on the web, it appears they had a 1 meg volume pot and 300k tone pot. There was a .047 cap and a .0015 cap with a switch to select between the two. The controls were in a metal box which served as the ground (earth across the Pond from me) as well as the container and shield.

I have an old Kent monkey-on-a-stick pickup which sounds similar and is a quiet as can be when full up- all that shielding (full metal box around the pickup and the control circuitry) does a great job despite the pickup being single coil. It's quieter than any of my humbuckers.

**Patrick2** · 08-01-2015, 10:27 PM

Not too long ago, I had a tech tell me that he once had to open up an original RC1100 to rebuild it. He was surprised not to find any magnet in the pup. He knew that was impossible, but . . . no magnet was to be found anywhere. He contacted a pup builder and was told that the magnet was actually the bobbin itself. When it was molded, there were fragments of magnetized metal introduced into the mold along with the resin. So, the bobbin became the magnet. Any truth to this?

**Para** · 08-02-2015, 06:39 AM

I would have thought that a 1 meg pot would be rather bright sounding.

**rpguitar** · 08-02-2015, 09:14 AM

I installed mine with a 500k pot that is low profile enough for the pickguard (to clear the top). Sounds fine and rolls off just enough brightness for my taste with a smidge of volume reduction. Not a scientific contribution I guess, just a single data point.

**pingu** · 08-02-2015, 09:47 AM

Originally Posted by Patrick2

Not too long ago, I had a tech tell me that he once had to open up an original RC1100 to rebild it. He was surpriced not to find any magnet in the pup. He knew that was impossible, but . . . no magnet was to be found anywhere. He contacted a pup builder and was told that the magnet was actually the bobin itself. When it was molded, there were fragments of magnetized metal introduced into the mold along with the resin. So, the bobin became the magnet. Any truth to this?

don't have any info on that but it wouldn't
surprise me ... as they are very thin

i did read somewhere that the 1000 pu had
2 separate coils one for the 4 low strings and
one for the 2 top strings ... to balance the
relative volumes better ....

**Para** · 08-02-2015, 11:14 AM

Interesting, that means the pole pieces are screwed in the bobbin. I always understood they had 2 coils wound round different size magnets.

**Franz 1997** · 08-02-2015, 11:41 AM

Originally Posted by Patrick2

Not too long ago, I had a tech tell me that he once had to open up an original RC1100 to rebild it. He was surpriced not to find any magnet in the pup. He knew that was impossible, but . . . no magnet was to be found anywhere. He contacted a pup builder and was told that the magnet was actually the bobin itself. When it was molded, there were fragments of magnetized metal introduced into the mold along with the resin. So, the bobin became the magnet. Any truth to this?

A few years ago I bought an original DA 1100 from a US "dealer" , which arrived DOA. Since it seemed I had little to lose, since it didn't work, I opened it up. The problem was a corroded lead wire, but while I was in there I noticed the lack of a conventional magnet. Instead, the magnetic component was magnetised....rubber! I managed to fix the pickup, but was curious and verified on the net that indeed, the magnets were rubberised ferrite on original DA 1100s.

Just out of curiosity, I looked at the reissues on the Cordoba site and the new 1100s are also specified as ''rubber magnets". Incidentally, original 1100s often read 12K ohms or more, although the reissues are specified at around 6K

**Cunamara** · 08-02-2015, 12:36 PM

Originally Posted by Para

I would have thought that a 1 meg pot would be rather bright sounding.

If the tone pot was 1 meg like some folks do in Teles, yes. For the volume pot being 1 meg, I think it would basically make it transparent- as you roll off the volume the tone would change very little if at all until you'd rolled it off a lot. Like a treble bleed circuit on the volume pot without the extra cap and resistor. The switch between the two caps would modify the response of the tone pot.

**nopedals** · 08-02-2015, 02:03 PM

Here is a peek inside the control box of a circa 1965-1970 dearmond model 55. Perhaps some electroinics experts could describe what is going on there. A different pickup, but a dearmond single coil with volume and tone and pole piece screws, so I don't know why the model 1100 boxes would not be the same.

Reissue Dearmond RC1100 demo-wp_20150802_007-jpg

Reissue Dearmond RC1100 demo-wp_20150802_007-jpg

**KirkP** · 08-02-2015, 02:22 PM

The model 55 treble control is series RC connected to the pickup, before the volume pot. The output is the center tap (wiper) on the volume pot. Nothing unusual.

**2bornot2bop** · 08-02-2015, 02:38 PM

Originally Posted by rpguitar

I installed mine with a 500k pot that is low profile enough for the pickguard (to clear the top). Sounds fine and rolls off just enough brightness for my taste with a smidge of volume reduction. Not a scientific contribution I guess, just a single data point.

C'mon man, let's see it. It ain't everyday one gets to see a classic updated with an 1100. You've got great pho-tog skills!

**rpguitar** · 08-02-2015, 08:18 PM

My photo skills suck, but, ok...

Reissue Dearmond RC1100 demo-image-jpg

**2bornot2bop** · 08-02-2015, 09:03 PM

Originally Posted by rpguitar

My photo skills suck, but, ok...

Thanks! That's *itchin! Now, while you're at it, what about the Slaman? It arrive yet?

**rpguitar** · 08-02-2015, 09:32 PM

Separate post required for that! The Slaman is my #1 these days, it's a terrific guitar. That and the newly electrified S400 are occupying all of my time. I need to do demos, but I've been too busy with all manner of things... Sorry! I am notably lax in my NGD reporting duties.

**Patrick2** · 08-02-2015, 09:38 PM

Originally Posted by Franz 1997

A few years ago I bought an original DA 1100 from a US "dealer" , which arrived DOA. Since it seemed I had little to lose, since it didn't work, I opened it up. The problem was a corroded lead wire, but while I was in there I noticed the lack of a conventional magnet. Instead, the magnetic component was magnetised....rubber! I managed to fix the pickup, but was curious and verified on the net that indeed, the magnets were rubberised ferrite on original DA 1100s.

Just out of curiosity, I looked at the reissues on the Cordoba site and the new 1100s are also specified as ''rubber magnets". Incidentally, original 1100s often read 12K ohms or more, although the reissues are specified at around 6K

Thanks Franz. That's pretty much what I was talking about.