Hammond 1750 Series FYI - Paper Wound

[rp]

I stumbled upon this page, it has the bobbin type info that their PDF doesn't. Apparently, some of the Hammond guitar line OTs are wound on paper. Who knew, all these years I always figured they were just lower rated (ie re-rated for 80hz rather than 20Hz) or maybe just a cheaper wound 1600 series.

They must have retooled for the paper winding. Makes me rethink the effort they put into their guitar line, maybe it's very good? The old paper wound Hammonds I used to pull out of Traynors were great.

http://www.hammondmfg.com/guitarLineOT.htm

[David Root]

Very nice! Thanx for posting it. The .pdf now lists the bandwidth too, which is also new.

Tell me, how are the Traynor OTs different than the Fenders of the same size? I know Traynors don't sound like Fenders, but you have some experience with the old Traynors.

EDIT: I looked at the 100W Traynor and Fender .pdfs and part of the answer has to be the big difference in primary inductance, 53H Traynor, 22H Fender. This is reflected in the noted bandwidths, 50-12kHz Traynor, 70-15kHz Fender. I think the Traynor is bigger and heavier, same as a 100W Marshall OT is. The Marshall 100W OT pri. impedance is 76H! I believe the BF Twin OT was overwound on a 50W core, to reduce bass output so speakers wouldn't blow so easily, whereas the Traynor & Marshalls use a properly sized 100W core.

So the Traynor is more towards a 100W Bassman OT I think. Might be a good OT for a 100W Dumble build?

[randalp3000]

thanks, I've been on this page many, many times and never noticed the paper/bobbin column.

The 1760L Bassman OP with the 4,8,16 ohm taps is reasonably priced and sounds pretty good. I have 2 of the 1750V ac30 transformers and really like them. I also have one of the 50watt Traynor OP's that was going to be used for an AC50 build but I'm over that now and looking for a new project. Why are the Vox and Traynor transformers so much more expensive?

I wish CE stocked more of these and more of the Hi Fi OP's with the EZ wire secondaries. I need to contact Hammond to see what it takes to become a dealer.

I've had really good luck with these power transformers also. They have 115 and 125V primaries. The power around here is usually between 121-125v so it helps keep voltages in check especially the filaments.
http://www.hammondmfg.com/263.htm

[rp]

Tell me, how are the Traynor OTs different than the Fenders of the same size? I know Traynors don't sound like Fenders, but you have some experience with the old Traynors.

No idea comparative-wise, I was referring to the old Hammond iron in '60s-'70s Traynors. I was living in Montreal in the early '90s, it was pretty depressed then, lots of little urban hick mom & pop music stores and chock full of very excellent pawn shops. I used to grab YBA1 Bass Masters for ~$100 USA. For that you'd get 2-4 EL34 Mullards or 7027s, 3 Rogers 12AX7s, a handful of mustards, 3 husky paper wound Hammonds from about 1969, and a nice chassis to work on. You could pretty much grab one a week! I built 3 5F6A/Marshalls using Traynor 50W iron and all sounded great.

I used to look forward to heading out into 20 below to see what fun stuff I'd find that day. I really enjoyed my time in the past, the modern world has killed off a lot of good things, including scavenging. Grabbed a MINT '57 Rolex Submarine for $1000 USA in a Montreal pawn too. That stuff is all gone now, the modern world has killed off my favorite pass time of scavenging for cool shit. Nothing but '80s Chinese crap in thrifts and pawns now.

[rp]

I was just looking at the 1750L for a Rocket as i need 4 ohm taps that the 1750V lack.

I've had really good luck with these power transformers also. They have 115 and 125V primaries. The power around here is usually between 121-125v so it helps keep voltages in check especially the filaments.

I've said this before here, screw the 200 Series PTs. Those 115/125 taps will give you either too low an HT with a proper filament V or the opposite. Use the 115V taps and you get above 7V on the heaters - what damn use is that? For a little more use the 300 series, they are dead on and if your amp ever needs to travel it can.