Vintage Celestion Guitar Speaker Cones

Vintage Celestion Guitar Speaker Cones

Tone Is In The Cone

Over the years Celestion have used various cones from different suppliers, all slightly different in tone.

Celestion have never really given any information out about their suppliers. Therefore a lot of the details about them that you might read elsewhere, often just turn out to be nonsense that has been repeated and passed down the grapevine over the years.

The information I have written on this page is based on my own experience dealing in vintage speakers. It may conflict with information you have picked up elsewhere, but is accurate to the best of my knowledge.

Quick links

About Recones
‘Large Rib’ Pulsonic
Kurt Mueller
‘Large Rib’ Kurt Mueller

Some Common Misconceptions Debunked!

The Kurt Mueller Myth

If your speaker has a ‘1777’ or ‘444’ stamp, it does not automatically mean it is a Kurt Mueller cone. These are actually Celestion part numbers and can be found on several different cone types.

1777 stamped Pulsonic cone - not a Kurt Mueller!
1777 stamped Pulsonic cone – not a Kurt Mueller.

Blank cones and handwritten markings

If your speaker has a hand written code, or is completely unstamped, this does not automatically mean it has been reconed. If it looks original and sounds original – it is probably original.

The ‘RIC’ cones from the mid 1970’s are particularly common to find with either a yellow chalk marking, or no marking at all.

RIC cone with handwritten 1777 code - not a recone and not a Kurt Mueller.
RIC cone with handwritten 1777 code – not a recone and not a Kurt Mueller.

About Recones

Old recones are usually fairly easy to spot because they will look a lot different to the original Celestion cones. Watch out for odd looking cones, over-sized or incorrect dust caps, unusual looking lead wire glue (the two black marks near the dust cap), and spider supports that overlap the frame rim or just look too new.

When reconing a speaker, the original gasket surrounds would often be re-used, especially if they have a date stamp on them. So an original gasket does not automatically mean the cone is original too. The white manilla gaskets are particularly easy to remove and re-fit.

Most speaker repair places will leave a sticker on the frame of the speaker somewhere and that is often the first visual clue.

Re-coned speaker with original gasket
Re-coned speaker with original gasket re-fitted

A common recone to find on older speakers is the Waldom recone kit, which usually has the cone stamp WF***.

Recones are not the end of the world and can still sound good if they are not coil rubbing. However, any collector value goes right out the window once the original cone is gone. So never pay top dollar prices for a reconed vintage speaker.

Celestion factory recones

Celestion would sometimes print a new date stamp when reconing a speaker. This is usually accompanied by an additional ‘RW’ stamp, and can often be found on the old alnico’s from the 60’s. Obviously if it is a very old recone from when Celestion were still using pulsonic cones then this should not affect value too much and will still be a desirable speaker to most people.

Early 60's Vox blue speaker, reconed & restamped - 13th July 1970
Early 60’s Vox blue speaker, reconed & restamped – 13th July 1970

Cone Types

Shown below are some of the most commonly found cones from the 1960’s and 1970’s.

Pulsonic Cones

The pulsonic cones first appear around mid 1962, most notably on the T530 “vox blue“. They are easily the most sought after cones by guitarists because they have a superior quality to their tone that cannot be found in any other speaker cone. Their slightly softer and more ‘fluid’ sound is particularly popular with blues and classic rock guitarists.

An early H1777 Pulsonic cone
An early H1777 Pulsonic cone

Pulsonic cones are highly collectable due to their association with the legendary guitar players of the period such as Jimi Hendrix and The Beatles, and their use in the old 60’s Marshall and Vox amplifiers.

A late 60's 003 stamped Pulsonic cone
A late 60’s 003 stamped Pulsonic cone

Legend has it that a fire at the Pulsonic factory in late 73 destroyed the magic formula for making those sweet sounding cones. Nobody has successfully managed to replicate them in my opinion, though several boutique brands have tried, as well as Celestion themselves with their Heritage greenback range.

There are various cone stamps to be found on pulsonic cones, largely depending on when they were made. Some stamps are less familiar than others, including the ‘1777’ stamp which people often incorrectly assume must be a Kurt Mueller.

A while ago I found an unusual T652 speaker with both the H1777 and 003 stamp on the cone. I decided to include it here as my evidence for the non-believers. Same cone, two different stamps:

An unusual cone with both pulsonic cone stamps.

Pulsonic cone stamps through the years

75Hz Pulsonic Stamps55Hz Pulsonic Stamps
H1777 or **/H1777mid 1962 to 1966SP444 or **/SP4441966 to 1967
003 or **/003mid 1966014 or **/014mid 1966
**/102/003mid 1962 to 1967**/102/0141966 to 1967
** 102 003mid 1962 to Apr 1971** 102 0141966 to Apr 1971
102/3 or 102 3Apr 1971 to Apr 1973102/14 or 102 14Apr 1971 to Apr 1973
3Feb 1973 to Apr 1974141972 to Apr 1973
1777Feb 1973 to Apr 19744Apr 1973 to Apr 1975
1777 (large rib)Aug 1974 to Apr 1975102/30Apr 1971 to Apr 1973
5Apr 1973 to Apr 1974
0444 (large rib)Aug 1974 to Apr 1975
'**' = a variable two digit number said to represent the week of the year the cone was made
Note - dates shown are for very rough guidance only - expect transitional overlaps.

‘Large Rib’ Pulsonic Cones

These cones are basically the same as the earlier pulsonic cones but have noticably larger ‘ribs’ (proper name is ‘corrugators’). They can usually be found on ‘creamback’ speakers made between mid 1974 to mid 1975.

If the fire in 73 story is true, these were possibly made from the remaining stock of pulp.

The typical cone stamps are ‘1777’ for a 75Hz cone and ‘0444’ (notice the leading zero) for a 55Hz cone.

Transitional Pulsonic cone
‘Large Rib’ Pulsonic cone

Their sound is very similar to the previously mentioned pulsonics, but you might notice they are marginally brighter at lower volume levels. The beauty of these cones is that because they were produced a little more recently they tend to turn up in better condition than the older pre-rola speakers and are usually a lot cheaper to buy!

Most people dismiss these cones as Kurt Muellers because of the cone stamps. A classic example of how a lot of guitarists use their eyes when evaluating gear, rather than their ears!

‘RIC’ stamped cones

Most commonly seen on greyback and creamback speakers from around August 1973 to mid 1975, and on most ‘G12’ alnico speakers made before mid 1962. These cones were probably made in house at Celestion’s Thames Ditton factory (in my opinion).

RIC cone
RIC cone

They are usually fairly easy to identify by their blue/grey appearance, and they do not usually have a ‘shadow’ around the dustcap like a pulsonic or mueller cone.

Their sound is quite distinctive, and they are generally under-rated by most people. Often described as ‘dark’ sounding which may be unfair. They are very nice sounding cones in my opinion, with a smooth sound that can tame a harsh sounding amplifier, and they can be superb for lead work, although do lack some of the sparkle found in other cones and can be a bit ‘boxy’ for rhythm playing. Try mixing with a pulsonic for the best of both worlds.

Other stamp variants found on non-greenback models include ‘NIB’, ‘ROB’ and ‘JIL’, which I am confident are cones from the same factory but made to different specifications. The NIB cone was standard on the 10″ speaker model 7442 used by Marshall all the way through from late 1960’s to mid 1970’s, and is a very highly regarded speaker amongst Marshall collectors.

Stamp variations:

It is common to find the RIC cones without any stamps or other markings, particularly around early 1974. So be careful not to dismiss them as recones. I have definitely owned more without stamps than with.

Another variation is a handwritten 1777, 1444 or 444 in yellow chalk. Again, these are not recones, and are fairly common for late 73/ early 74.

98700 cones

These are very rare cones and were only used for a short period. They can usually be found on creamback speakers made between May and July 1974 – with date stamps EG, FG, or GG.

The rare 98700 cone
The rare 98700 cone

Very little is known about them, but I can tell you they are some of the nicest cones you can find and are well worth looking out for. Please do not dismiss them as recones. The tone is slightly less mid focused than the pulsonics, so a bit flatter sounding, but still a very nice smooth & fluid tone, not harsh or gritty.

Kurt Mueller Cones

These are the most common cone to find on the late 70’s and 80’s speakers; the ‘blackbacks’, G12-65’s and G12-80’s etc. They first appear early 1975 and were used well into the 1980’s.

Their tone is a bit more aggressive than the pulsonic cones and may be more suited to your style if you play heavy rock. They are a good sonic match to the master volume Marshall amps of the period.

Kurt Mueller cone
Kurt Mueller cone

Usually stamped 1777 (75hz cone) or 444 (55hz cone), depending on the speaker model.

They tend to be pale grey in appearance wth a slight shadow around the dust cap. Although colouration does seem to vary and can appear darker or more blue in some cases – this can happen if a different dye has been used for the paper pulp.

Stamp variations:

The first Mueller cones from early 1975 are usually unstamped, or may only have a small single digit number written on them in marker or chalk, with a brown colouration to the doping.

Through mid 1975 some Muellers have their codes handwritten in black marker.

The white 1777 and 444 stamps only seem to appear on Mueller cones towards the end of 1975. Earlier 1777 stamps are unlikely to be Muellers, and are probably Pulsonic or large rib Pulsonic.

Some late 70’s and 80’s cones are stamped in black ink, and can often be difficult to see.

‘Large Rib’ Kurt Mueller Cones

These cones are a variation of Kurt Mueller (in my opinion – could be wrong) and can be found sporadically on blackback speakers and G12-65’s made in the late 1970’s. They basically sound near enough the same as the previously mentioned Kurt Mueller cones. However at low volume they are a little bit clearer and brighter sounding to my ears, which I do prefer.

Large rib Kurt Mueller cone
Large rib Kurt Mueller cone

​The most notable difference is the larger ribs on the cone and the lack of any cone stamp. The back of the cones are usually darker (more black in appearance) than the usual Kurt Mueller cones.


  1. Rick Zipp Zipp
    May 14, 2019 / 4:20 am

    I’d like to find out what drivers I have year etc etc
    FJ18X T2168
    1777 on cone
    Thanks for considering

  2. Mark
    May 19, 2019 / 11:39 am

    Hello Brian – i’ve had a speaker for 30 years unidentified and it would just be novel to know its identity though i feel its probably a Fane not a celestion. On chassis it has 1221457 and 1198 * (< * = 4 or a 1 ). It appears to have a large rib cone, 8 ohm with big magnet and the large dust cap. I just wondered if the codes gave it away to you ?.

    Great site – Kind regards

    • Brian Harding
      May 20, 2019 / 9:56 am

      Hi Mark, can you email me some photos please? It does sound like a Fane speaker to me. Most of them have the ‘122/’ prefix to the model number.


  3. Dominic
    June 7, 2019 / 9:12 am

    I have 2x T1281 G12H 55 Hz greenbacks from end 73 and beginning of 74, both have RIC1 cones. Shouldn’t they have been creambacks?

    • Brian Harding
      June 8, 2019 / 6:49 pm

      Hi, well end of 73 into early 74 would normally be greybacks, but you can find the green still being used into 74 yes. It is nothing to worry about. There were transitional overlaps. Also previous owners might swap them around or buy them online as spares.


  4. jonny
    July 17, 2019 / 2:52 am

    hi, i actually worked at meullers years ago for a while. the cones are made in a mesh mould 4 on a rotating machine,and the papers is poured in from a massive vat high up. there was a room full of these machines, we would churn out 1000’s per week, there was no custom, hand babying, intense criteria selection- bang ’em thru, like cheeseburgers , we are running to a timeline..if it works, and no faults- its all good. the paper pulp was just a speaker paper- what type i never saw any different type, what changed was the mesh grill and corresponding piece that pressed down. sometimes there would be 2 stuck together (rejected) but the moulds were all different. there was alot of steam, as the paper was dried out by the heated part, steam, dirt, dust.. sometimes scrap cones would be chucked back into the vat to go through the process- that was the dirtiest job you will ever have seen, climbing up there. the original moulds would be the way to get the original tone, as the thickness could vary, i sorted 1000 s out, chucked 1000’s. the experts in the field probably have original cones, they have measured, and cut through samples. thats my 002cts.. it is like the chase for period strat scratch plates, paying a fortune, or a 60’s wound pickup..

    • Brian Harding
      July 17, 2019 / 10:57 am

      Hi Jonny, interesting info, thanks for sharing.


  5. Chris
    August 8, 2019 / 5:07 am

    Thanks for the site and sharing this info. I have a 63-ish AC30 that has the original blues and was curious to learn more about the speakers/cones as they make all of my amps sound magical. They both are stamped RIC or R/C Rola Celestion. Even Jim Elyria’s Vox book doesn’t have much info on these cones and mostly focuses on Pulsonic and Kurt Mueller cones. Are there any vintage 10″ speakers that sound similarly smooth/dark you can recommend for an AC10?

    • Brian Harding
      August 12, 2019 / 12:23 pm

      Hi Chris, fwiw I’m not convinced the RIC code represents ‘Rola Celestion’. Just because there are other cone stamps on Celestion speakers that appear to be from that same cone manufacturer. I’ve definitely seen ‘NIB’, ‘ROB’, ‘JIL’, and there are probably loads of others I haven’t come across yet. As for 10″ speakers definitely try the 7442 model ceramic speaker. This came with the NIB cone as standard all through the 1960’s and never the pulsonics. Find them mostly in Marshall gear. 10″ alnicos are more difficult to find. Elacs were a popular choice at the time but they are quite bright and chimy. Goodmans would probably give you a darker tone than the Elacs.
      Hope that helps,

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