OT for ac30: A470s or classictone's ac30 tranny (40-18049)?

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Roe
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OT for ac30: A470s or classictone's ac30 tranny (40-18049)?

Post by Roe »

Have anyone comparred a dyna type a470 to an ac30 OT? is the latter more lofi or what?

This is for an ac30 inspired build with top boost, ef86 and the normal channel. I'm using a weber 6v30 kit, mustards and sozos, and some old resistors.
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Roe
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Re: OT for ac30: A470s or classictone's ac30 tranny (40-18049)?

Post by Roe »

from what I can gather the a470 is beefier than a typical ac30 ot.

Triode electronics says that the A-470 is intended for HiFi use, and that it has a broader band-width which isn't as desirable for guitar amplifiers. They add that the broader bandwidt tends to make your guitar tone rather shrill on the high end. Also, the a470 has UL screen taps which would not be used in the AC30 circuit.

The 40-18049 on the other hand is much closer to the original transformer that came in the AC-30's, The winding style is the same, and it also employs a paper bobbin like the original.
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Roe
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Re: OT for ac30: A470s or classictone's ac30 tranny (40-18049)?

Post by Roe »

any comments?
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Cliff Schecht
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Re: OT for ac30: A470s or classictone's ac30 tranny (40-18049)?

Post by Cliff Schecht »

That's bullsnap about the A470 being no good for guitar use. Heck almost every build I do for myself uses hi-fi transformers. I'm not worried about the high end in a transformer either, I'm worried about the low end response.
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sliberty
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Re: OT for ac30: A470s or classictone's ac30 tranny (40-18049)?

Post by sliberty »

The only value I can add in this thread is to say that I used an a-470 in my Rocket build, and the results are nothing short of wonderful.
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M Fowler
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Re: OT for ac30: A470s or classictone's ac30 tranny (40-18049)?

Post by M Fowler »

Not sure about what your asking but I have used the A-470-S in a few builds and they sound great.

www.rjguitars.net sells the Heyboer HTS-8093-1 which is based off this OT and I have used that OT with great results as well.
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C Moore
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Re: OT for ac30: A470s or classictone's ac30 tranny (40-18049)?

Post by C Moore »

Roe wrote:from what I can gather the a470 is beefier than a typical ac30 ot.

Triode electronics says that the A-470 is intended for HiFi use, and that it has a broader band-width which isn't as desirable for guitar amplifiers. They add that the broader bandwidt tends to make your guitar tone rather shrill on the high end. Also, the a470 has UL screen taps which would not be used in the AC30 circuit.

The 40-18049 on the other hand is much closer to the original transformer that came in the AC-30's, The winding style is the same, and it also employs a paper bobbin like the original.
Can I ask a general question?
How or why would a "Hi-Fi" OT make the treble frequencies of a guitar amp sound shrill. I always read that "big iron" enhances/improves bass response. Why would it do the opposite for the higher frequencies?
Thanks
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jaysg
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Re: OT for ac30: A470s or classictone's ac30 tranny (40-18049)?

Post by jaysg »

I've heard that the basic Heyboer AC30 OT is great and the MM Woden is the shiz. ymmv

PS. That said, apparently you still have to buy the Celestion Blues if you're serious about it.
Roe
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Re: OT for ac30: A470s or classictone's ac30 tranny (40-18049)?

Post by Roe »

I have some blues laying around anyway. I'll prob go for the vox ot. it has less bandwidt than the 470
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Roe
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Re: OT for ac30: A470s or classictone's ac30 tranny (40-18049)?

Post by Roe »

update: the Magnetic ac30 works well. seems to sounds like a vox should.
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Reeltarded
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Re: OT for ac30: A470s or classictone's ac30 tranny (40-18049)?

Post by Reeltarded »

If I am enamoured with a Voxy sound, I am probably not trying to emphasize the lowend.

TB tingles to me are in the Cut.
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