Hi
I´m building a trainwreck express clone and I am using the hammond 1650h
Datasheet with secondary hookup data:
http://www.hammondmfg.com/pdf/5c0051-52.pdf
I want to be able to use both 4 ohm and 8 ohm cabinets, but the wiring one these transformers is a bit tricky, as seen in the datasheet.
Will it work if I wire it up, as I have drawn in the attached file?
Thanks in advance
I´m building a trainwreck express clone and I am using the hammond 1650h
Datasheet with secondary hookup data:
http://www.hammondmfg.com/pdf/5c0051-52.pdf
I want to be able to use both 4 ohm and 8 ohm cabinets, but the wiring one these transformers is a bit tricky, as seen in the datasheet.
Will it work if I wire it up, as I have drawn in the attached file?
Thanks in advance
The spec doc says "......Due to the unique interleaving of the windings BOTH secondary windings must be engaged to meet specifications..." To me that means both windings need to be driving their own respective speaker jack, and at the same time, for the figures to be accurate. Maybe this is for driving 2 different "types" of speakers at the same time? Woofer + horn?
I also was questioning the secondary. Is this tranny already purchased? It really is designed for hi-fi use since it has UL primary and a freq. response of 30-30kHZ. Also agree with jjman about secondary needing both windings to be hooked up. Most guitar OT's only need a response about 50-70 Hz on the low end and about 8-10kHz at the top.
Last edited:
No,
It means all windings must be used, as in if you want it used as a 4 or 8 ohm secondary, BOTH 4 ohm windings must be connected in parallel and in phase (look at spec sheet for correct wiring). If you want 16 ohms out, both 4 ohm windings must be in series to get 16 ohms.
Because the transformer is configured weird, a simple impedance selector switch can't be used to select output impedance.
If you haven't bought the transformer yet, get the 1650H-A version, it has the common 0-4-8-16 ohm winding configuration that is standard. It costs a few dollars more.
Hammond transformers are indeed made for Hi-Fi use but work well in Guitar and especially bass amps. Don't worry about the UL taps, just tape them with electrical tape and don't connect them to anything.
It means all windings must be used, as in if you want it used as a 4 or 8 ohm secondary, BOTH 4 ohm windings must be connected in parallel and in phase (look at spec sheet for correct wiring). If you want 16 ohms out, both 4 ohm windings must be in series to get 16 ohms.
Because the transformer is configured weird, a simple impedance selector switch can't be used to select output impedance.
If you haven't bought the transformer yet, get the 1650H-A version, it has the common 0-4-8-16 ohm winding configuration that is standard. It costs a few dollars more.
Hammond transformers are indeed made for Hi-Fi use but work well in Guitar and especially bass amps. Don't worry about the UL taps, just tape them with electrical tape and don't connect them to anything.
Last edited:
Already bought, unfortunately.
I dont really need the 16 ohm winding. If I only use the 4 & 8 ohm option, wouldn't it work with a standard rotary switch?
I dont really need the 16 ohm winding. If I only use the 4 & 8 ohm option, wouldn't it work with a standard rotary switch?
Wiring for 4 and 8 Ohms is identical, just select the approriate output lead. The "tricky" switching is only required if you want 16 Ohms too. A simple toggle swirtch will do for 4 and 8 Ohms. When selecting a speaker impedance switch remember that 50 Watts into 4 Ohms is 3.5 Amps RMS. Most switches will handle that but do check.
Also - this has been considered before and you can purchase a switch to do 4 8 and 16 Ohms.
https://www.tubesandmore.com/products/P-H1600
Cheers,
Ian.
Also - this has been considered before and you can purchase a switch to do 4 8 and 16 Ohms.
https://www.tubesandmore.com/products/P-H1600
Cheers,
Ian.
Last edited:
- Status
- Not open for further replies.