Help converting Cornet2 for MC.

robertwstephens · « **on:** 16 May 2006, 08:40 pm »

Hello!
I want to convert to a moving coil cartridge using my Cornet2 and need some advice. I want to use the Lundahl LL9206 step ups. Can I put them in the Cornet2 chasis away from the transformer or should I get the stand alone case? I think I would wire them to the input jacks and the go from the Lundahl's into the circuit board. I want to get a Denon DL-103R catridge and can set it up for 14,20 or 26 dB of gain. It is .25mV and 14ohms impedence. Any suggestions on which gain I should use for this cartridge? I have a Grado reference platinum cartridge right now and am looking to upgrade as usual. Thanks in advance for the help! Peace. Robert

analog97 · « **Reply #1 on:** 16 May 2006, 09:23 pm »

Robert,

I use a Denon 103 (0.3mv) with the Cornet2 and have a separate transformer chassis. Mine is a Denon and is 20db (10x) gain. That is PLENTY of gain for my system. I can not comment on the Lundahls, but it just seems to me the headaches of fitting them in the Cornet2 (and possible hum, etc troubleshooting) do NOT outweigh the benefits of a separate chassis. Each must choose accordingly. Good luck.

hagtech · « **Reply #2 on:** 16 May 2006, 11:05 pm »

You can put the trannys inside the chassis near the first 12ax7. But you cannot route the wiring past the power tranny to the back of chassis. That's the problem. It's the wiring that picks up hum (magnetic).

jh

hagtech · « **Reply #3 on:** 19 May 2006, 12:58 am »

I found some old LL9206 I had laying around (used them in a Cornet2 prototype), so I thought I would try install them into a Classic Cornet. Well, they fit easily. I epoxied them right to the I/O panel above the input jacks.

Wired them up for 1:10 gain. One channel worked fine, but the other had a broken secondary coil (9-10). I must have unsoldered the internal joint with all of the handling and messy deconstruction from the original circuit board. Anyway, the wiring wasn't all that hard. I just used a thin bare copper wire to wind around each post.

Too bad it's no good. This would have been a nice unit, as it also has upgraded capacitors. The important thing is that this can be done. Just keep the cabling away from the power transformer.

jh

robertwstephens · « **Reply #4 on:** 19 May 2006, 03:20 am »

Thanks for the info Jim. You went above and beyond the call of duty as usual. Peace. Robert

analog97 · « **Reply #5 on:** 26 May 2006, 09:08 pm »

I have a Cornet2 and have been using an inexpensive Denon Tx and this project intrigues me. Maybe my "nerd" gene has been up-regulated. However, the I/O jacks on JH's picture of the Classic Cornet are different from both the type of jack (PCB-plug-in) and placement. Plus, the wiring would require this novice to have a pretty clear picture of how/where the wires are routed. Also, it seems to this novice that an insulated wire, type-to-be-specified, would also be necessary. If anyone has a really good picture of the inside of a Cornet2 that has the standard plug-in RCA's with the Lundahl 9206's, I would greatly appreciate it being posted. I'd really like to try this. Thanks for any info, folks.