More uses for a Hammond choke?

[tpatton]

I have two Hammond 155J chokes in each of my two Seductions, replacing 1K ohms resistors.  They seemed to help noticeably. Can I alsouse Hammond chokes either in my Paramour II's or in my S.E.X. amp?  If so, can someone tell me where to use them and which specific ones to get?  Thanks!

[Paul Joppa]

Paramour II is easy. The stock plate choke (Triad C7-X, which I think is currently made by Hammond - 10 henries, 90mA, 270 ohms) can replace the 270 ohm 5 watt resistor in the power supply, and there is even a place to mount it behind the power transformer.

In the original SEX amp, the 680 ohm 3 watt resistors (T6 to T11 and T26 to T31) can be replaced with chokes. The 154G at 700 ohms, 9 henries, 40mA looks suitable. I don't see a place to put it, btu Bottleheads are pretty inventive...

[ssssly]

I'll double check that it was the 154G. But when I built my Crack I had mocked up some Hammond chokes to replace those resisters. The would have fit. Mocked up some braces that screwed into the bottom of the base to hold them in place. Also needed taller feet. Was about 2" I think.

Ended up putting some very large motor run caps in for the PSU caps instead. Unfortunately in the stock base, both would not fit.

[tpatton]

Thanks, Paul.  I've just ordered a pair of CX7's from Newark, promotional price $8.14, not bad when compared with the twice-as-expensive Hammond 155J's.  I'll leave the SEX amp alone.  It's hard to imagine that my Paramour II's can sound better than they do right now, but it will at least keep me out of (other) mischief to do this little project.

[tpatton]

I looked for, and couldn't find, that Paramour II 270 ohms resistor that Paul J said I could replace by a C-7X choke.  Then, finally, I saw a C-7X choke already there--put there when I did the Magnequest transformer/choke upgrade.  Is there anywhere else I could put the two C-7X's I just bought from Newark?  In a SEX amp or in a Seduction?  Almost certainly not.  Next question: would anyone like to buy my two extra C-X7's for $16 plus shipping?  That was a sale price: they're ordinarily over $10 apiece.  If I could use them in the SEX amp, I wouldn't mind building a new chassis for it, to make room for them.  But using them in the SEX amp, as I said, seems very unlikely.

[tpatton]

Let me mention (what I should have said earlier about my Paramount II's) that my SEX amp has undergone the Magnequest transformer/choke upgrade.  Might this possibly make a pair of C-X7 chokes usable in it?  I can make physical space for them, by building a larger chassis. But no resistors are in sight, I would guess, for these C-X7's to replace.

[Paul Joppa]

In the previous SEX amp, there is a 680 ohm resistor between T6 and T11, and another on the other side (T26 and T31?) Those can be replaced with chokes. I don't know if there's room, but mounting them on the side walls of the base so they are under the output transformers will keep the magnetic fields perpendicular fro minimum interference.

This does not apply to the new version 2.1 SEX amp.

[tpatton]

I guess this is obvious, but just to be dead sure: is the C-X7 choke, 270 ohms, okay to replace a resistor more than double that ohms value?  If so, I can use my C-X7's, and am happy about that, and also about the fun of a new project: building a new, roomier chassis for my SEX amp.

[Paul Joppa]

Yes, it's OK. It will raise the high voltage by 12 or 13 volts, which is not a big deal out of 366 volts at T11.

[tpatton]

I put the C-7X chokes into my SEX amp without doing a new chassis.  I had already put a 1" strip below the stock chassis, for some reason, so was able to mount the chokes just above it, screw holes 1/4" above the stock chassis bottom.  I extended the chokes' wires considerably, so I can still get the top plate and everything built onto it out, clear of the chassis, if it ever needs to be worked on.

I hadn't listened to the SEX amp for some weeks--Paramour II's instead--but still, I thought the new chokes made for a dramatic improvement.  In the noise floor, in particular.  With no signal, I measured 0 millivolts for the left channel and 1 millivolt for the right.  That's only a shade better, if any, than the Paramour II's, but my impression was of a significant improvement.

I can't download a picture here--I don't know how to reduce pixels and make my pics small enough--but if you want to see how I did what I described above, email me at [email protected].  Thanks to Paul J in particular, for encouraging me to make this move and for telling me how.