Original early '70's G12h 75hz - recone with 55hz cone?

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vmaxvmax
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Original early '70's G12h 75hz - recone with 55hz cone?

Post by vmaxvmax »

Hi,

I have a few old early T1217 '70's G12H Greenbacks that came out of an Orange 4 x 12 cab which I chopped up back then due to the weight...

One of them is in my 1974x style 18 watt self build. It sounds good but I wonder if a bit more bottom end weight might be possible without adding any 'messiness' in the bass.

I recently re-coned one with a genuine Celestion T5535BWR kit (the same cone that Celestion use in their G12H Heritage speaker) as advised by Celestion. It sounds good now it's played in. The originals sound a little more 'airy' and their cones seem a little lighter/more flexible, most likely due to their age. Both the originals and the re-cone sound equally good if ever so slightly different.

One of the other originals needs a re-cone now. I'm wondering about using a 55hz Heritage T5537/R re-cone kit... Is it likely to give me a little more bottom end whilst retaining the overall sound of my 75 hz speakers without 'messing' up the bass?

I have no experience of the original 55hz models... What do you reckon? Anyone tried this?

Thanks for any views in advance.
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Re: Original early '70's G12h 75hz - recone with 55hz cone?

Post by zaphod_phil »

First of all don't trust Celestion's advice. The people who really knew those speakers no longer work there, and the factory that made the original legendary-sounding Pulsonic cones burned down many years ago. Unless your current cones are badly wrecked don't change them, as your speakers will lose their market value.

Opinions on the 55Hz cones are divided. Some people like them, some don't so much. If you're mainly playing single-coil pickups then they're probably a good idea. With humbuckers, possibly less so.
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Re: Original early '70's G12h 75hz - recone with 55hz cone?

Post by vmaxvmax »

Thank you for replying!
zaphod_phil wrote:First of all don't trust Celestion's advice. The people who really knew those speakers no longer work there, and the factory that made the original legendary-sounding Pulsonic cones burned down many years ago. Unless your current cones are badly wrecked don't change them, as your speakers will lose their market value.
Unfortunately I don't have that choice as the speaker in question was re-coned some years ago (not by me but for me...) but with the wrong cone - it's way too stiff and sounds very 'boxy' compared with both the original unchanged speakers and the speaker I recently re-coned myself. As I said the one I re-coned recently actually sounds good and that was done with a re-cone kit advised by Celestion - so in this instance the advice was good! :) Clearly I would rather not have to re-cone - though the value doesn't matter to me as I have had them from new and don't intend selling them (my children might feel differently about their value though!).

I am aware that too often the original G12H's get re-coned with the wrong kits. Ebay sells loads of re-cone kits for 'Greenbacks' without seemingly any discrimination between models! :o

I assume that my properly re-coned speaker sounds like the Heritage (that is what the re-cone T5535BWR kit is for) albeit with an aged magnet.
zaphod_phil wrote:Opinions on the 55Hz cones are divided. Some people like them, some don't so much. If you're mainly playing single-coil pickups then they're probably a good idea. With humbuckers, possibly less so.
Due to my experience so far - i.e. the Celestion T5535BWR kit sounds as it should now it's played in if slightly 'tighter' than the 'untouched' ones - I am willing to trust the 55 Hz kit - if it will give me a bit more bottom end without going flabby on me - I don't want the mids and top to change too much. I do use a single coils but also humbuckers sometimes. It will go into my self built 18watt, single channel, single tone 1 x 12 with open back cab. The cab is virtually identical to a Marshall 1974 but slightly deeper (250 x 610 x 500 as opposed to 229 x 610 x 500).

I guess the problem is that I have not and will not have the opportunity to audition any 55 Hz Heritage speakers, so I'm asking for views (I know they will be subjective) on what the differences are in adjectives (bearing in mind that my re-coned speaker will still have the old magnet)...

If you or anyone else has been able to make that comparison - you experience would be appreciated.

I really appreciate your help. :D
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Re: Original early '70's G12h 75hz - recone with 55hz cone?

Post by zaphod_phil »

vmaxvmax wrote:As I said the one I re-coned recently actually sounds good and that was done with a re-cone kit advised by Celestion - so in this instance the advice was good! :) ....I am aware that too often the original G12H's get re-coned with the wrong kits. Ebay sells loads of re-cone kits for 'Greenbacks' without seemingly any discrimination between models! :o I assume that my properly re-coned speaker sounds like the Heritage (that is what the re-cone T5535BWR kit is for) albeit with an aged magnet.
Let me clarify a little more. The problem is that for the early Greenbacks, G12H's and Alnicos (from the 60s to mid 70s), even the "right kit" may be wrong, although still pretty good. Most of those early speakers used Pulsonic cones, which BTW sounded fabulous. Celestion also used Kurt-Mueller cones, and these became the only choice after Pulsonic's factory burnt down in 1974. So if your speakers are post 1974 then you probably do have the correct cones. If they're pre 1974, then you probably don't have the right cones, although they're still good cones in their own right. I hope that makes a little more sense now. :)
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Re: Original early '70's G12h 75hz - recone with 55hz cone?

Post by vmaxvmax »

Yes, understood! Thank you.

Mine are actually 1974 with the RIC (R1C?) cones - which would explain why the re-cone kit for the Heritage speaker sounds alright - it's probably as close as possible to my original cone.

I'm still interested to hear your subjective views on the what the difference between the 75hz and 55hz speaker is...
:)
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Re: Original early '70's G12h 75hz - recone with 55hz cone?

Post by zaphod_phil »

I've not personally had the opportunity to try out the 55Hz version. I suspect they would work better in a closed back cab than open back. I've only used the 75Hz variety and have been very pleased with them.
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Re: Original early '70's G12h 75hz - recone with 55hz cone?

Post by Mr_dB »

I think maybe if you're looking for more low end from a 1974x type amp, it would be more productive to play with coupling cap values, or the cathode bypass cap on the output tubes.
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Re: Original early '70's G12h 75hz - recone with 55hz cone?

Post by abnerfm »

vmaxvmax wrote:
Wed 08/28/13 8:20 am
I guess the problem is that I have not and will not have the opportunity to audition any 55 Hz Heritage speakers, so I'm asking for views...

If you or anyone else has been able to make that comparison - you experience would be appreciated.
Hi there. This is my forst post on this forum, so, I hope it will be helpful. I have both the 55 and 75 Hertz G12H Heritage speakers... not a world of difference... to my ears, the biggest difference is not in the bass response, but in "perceived brightness"... as weird as it may seem, the bass (55Hz) cone actually sounds BRIGHTER than the lead (75Hz) cone. The lead cone has a bit more mids. That's all.

Cheers,
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Re: Original early '70's G12h 75hz - recone with 55hz cone?

Post by vmaxvmax »

abnerfm wrote:
Tue 01/28/20 10:35 am
vmaxvmax wrote:
Wed 08/28/13 8:20 am
I guess the problem is that I have not and will not have the opportunity to audition any 55 Hz Heritage speakers, so I'm asking for views...

If you or anyone else has been able to make that comparison - you experience would be appreciated.
Hi there. This is my forst post on this forum, so, I hope it will be helpful. I have both the 55 and 75 Hertz G12H Heritage speakers... not a world of difference... to my ears, the biggest difference is not in the bass response, but in "perceived brightness"... as weird as it may seem, the bass (55Hz) cone actually sounds BRIGHTER than the lead (75Hz) cone. The lead cone has a bit more mids. That's all.

Cheers,
Hi, thank you for your reply! Sorry I have only just seen it as the thread is fairly old!

Very useful to hear you experience.
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