Bugle to Cornet first listening and construction notes

BillEpstein · « **on:** 11 Jan 2006, 02:09 pm »

I took both to visit a friend who's a very experienced tube diy'er. He has an original Cornet playing through his own 300B amp.
It was immediately apparent to me how much better the Cornet images and retrieves inner detail but my friend was amazed at how good the all solid state Bugle sounded.
My Cornet has a non-stock chassis and Grayhill-switched inputs for phono and aux 1 and 2. His main concern about the build was the excessive length of the transformer leads (I cut them at 5" as suggested) and the fact that they weren't twisted together. I don't know why I didn't think of doing that.
This morning I twisted and braided the primary and secondary leads which still leaves them somewhat long. I'm going to get more quick-connects and go back and re-twist the leads, then cut them to the necessary length and only then attach the quick connects. I would humbly suggest the instructions might reflect this unless, Jim, you think otherwise.

Carlman · « **Reply #1 on:** 11 Jan 2006, 03:15 pm »

I'm convinced the Bugle is the best value in a solid-state phono preamp. The battery-op version sounds better than the AC-equivalent, to me though... so, if you leave it on, that's another $2 of batteries gone. Do they make rechargeable 9V?

BillEpstein · « **Reply #2 on:** 21 Jan 2006, 10:18 pm »

I got my 9V charger at Radio Shack, it's a combo uniy about $14.
And I think the 15V DC supply is more dynamic and just as quiet!

JoshK · « **Reply #3 on:** 21 Jan 2006, 11:12 pm »

I'd use a 12V SLA. I think there is a regulator in the power supply but if not it'd be easy enough to add one to drop the voltage to 9V. I think I asked about this to Jim and he said it was quite popular among Bugle owners.

robertwstephens · « **Reply #4 on:** 22 Jan 2006, 03:55 pm »

Could you submit a picture of what your project looks like with the twisted leads? I am on the home stretch of my cornet 2 build and have not assembled the transformer yet. I am curious about what you are suggesting. Peace. Robert

BillEpstein · « **Reply #5 on:** 23 Jan 2006, 12:37 am »

It's kinda helter-skelter but these aren't the typical AC connections, either. But Grandpa says to always twist AC, right?

robertwstephens · « **Reply #6 on:** 23 Jan 2006, 12:46 am »

Thanks for taking the time to post the picture! Peace. Robert

hagtech · « **Reply #7 on:** 23 Jan 2006, 02:35 am »

You gotta be careful when twisting pairs. They have to actually be "paired", as in equal and opposite currents. Otherwise, you are creating unwanted coupling between circuits. Don't just twist everything together. That's one reason I didn't specify a twist for the tranny leads. What you have is likely worse than no twist at all.

For this application it's not going to matter too much. The leads are far enough away from the sensitive circuit points, and the heat sinks offers shielding for the I/O connectors. If you have to twist, do the two green wires, the two red, the two yellow. Also twist the L and N coming in off the line. Short is good. And for sure, do NOT twist primary with secondary!

jh

BillEpstein · « **Reply #8 on:** 23 Jan 2006, 01:11 pm »

Thank you for that. The difference between the 2 photos is pretty scary.