(All other models available by order only)
VINTAGE U.K. GREENBACK CLONE
In our opinion the BEST 10" and 12" guitar speaker available!!
If you're looking for a speaker that replicates that true Vintage sound, then this is THE ONE!
Take a deep breath.............This is an interesting (and long!) story that originally came about several years ago when I took an old Vintage Celestion Greenback out of an early Marshall 12" Quad cabinet and took it to Victorian loudspeaker manufacturers, Lorantz, the company who took over the old Plessey plant.
Plessey was the company who in turn took over the ROLA plant. (Rola-Celestion is the original manufacturer of the Greenback and other vintage speakers which were also tied in with JENSEN speakers in the USA)
Why I have mentioned all this is that now Lorantz is owned and operated by the original speaker designer and head engineer at the old Plessey plant, and all the original equipment, including cone molds, are installed at the Lorantz factory. It is now a husband and wife "boutique" business, very high in integrity and true to the business ethics of earlier times when things were more about quality and reliability and less about cutting corners and maximising profits.
What I wanted was a speaker that would tonally sound as close as possible to the Celestion Vintage Greenback. After testing and plotting the old Greenback Lorantz came back to me saying that the only way that they could get this type of sound was to use a old style nomex copper wound voice coil, considered to be out of date technology, which would only have a power rating of 30 Watts. (Seemingly ridiculous in this age of high powered speakers)
Why on earth would anybody want a low powered speaker that sounds like an old Celestion???
My reply was "Do it, and I'll order enough for a production run"
So they did, and a great speaker success story was born.
True vintage warmth and fullness like the old Celestions but with the added advantage of superior efficiency resulting in a louder volume level for the same input power....not only that, but if you do cook 'em, they can be cheaply reconed. They follow the frequency plot of the original Greenback virtually indentically....within 2dB!!!
Everybody that has used these speakers has loved them, including all Melmusic staff...every one of us here use Lorantz in our personal rigs and we've all had the choice of whatever speaker we've wanted to. We just cannot recommend them highly enough!!! - Brad Coates Mng Dir. MELMUSIC
A short but necessary note: Please don't email or call us asking whether this would be suitable for your particular amp...we really cannot say. Sound and tone are subjective things over which even the most expert opinions differ. Please read the spec. sheet and decide for yourself.
We can tell you however, that if you like the old Celestion Greenbacks then you will like these because they are as close to the tonal qualities of the original as is possible.
(reprinted here Verbatim)
A sample of loudspeaker products produced in the 80’s. 8” and 10” loudspeakers produced from ex- Plessey components, 12” and 15” loudspeakers employing Etone cast aluminum frame.
Lorantz Audio Services was established in 1975, starting with many speaker
components and speaker tooling purchased from the closure of Plessey
Rola Co. Lorantz Audio Services commenced producing 6”, 8” 10” and 12” loudspeaker for the local OEM market. The product range diversified to
meet customer requirements, and the business was incorporated in 1990.
In 1995 Hazel and Michail Barabasz of Lorantz were awarded the "Service to the Industry Award” by the Melbourne division of Audio Engineering Society for the development and manufacture of loudspeaker technology of the highest quality for a period of over 30 years.
Hazel and Michail recipients of the AES
Services to Audio Industry award 1995.
In 1995 we purchase A Mori Sieke CNC lathe to achieve consistent high quality control standards in manufacturing. This also enabled us to manufacture critical tooling and aided in product development. Later we purchased a Kiwa machining center. Pole pieces machined on our Mori Sieke CNC lathe.
We attribute our success to our high technical skills diverse abilities and our ability to meet customer requirements. We recognize the critical aspects of design, and manufacture.
By necessity we therefore manufacture the majority of our loudspeaker components ie cones, suspensions, voice-coils, front-plates, rearplates pole-pieces and speaker tools are produced in-house. Our in-house manufacturing skills are a vital ingredient in our success and offer numerous benefits, the principal advantages being:
This knowledge and understanding ultimately leads to the acceptance of superior materials and technologies which enhance product performance, culminating in product superiority. We also recognize the importance of employing third party products/technology where they offer superior performance. An important facet in manufacture is to know your limitations, this then becomes strength. The ability to recognize and embrace product refinement is our strength, has enabled us to maintain market share against strong competition.
We have specialized in the Pro market specializing in sizes, 8”, 10", 12", 15", and 18". As we manufacture our own components we have the ability to supply a diverse product range, and includes sub-woofers and special audio file products volume permitting. At Lorantz we understand the need to be competitive, we must offer superior technology, superior production techniques, endorse quality control concepts. These concepts have established Lorantz as a preferred supplier for export markets and demanding applications. Product knowledge is vital for long term prosperity and only achievable with a better working relationship between supplier and customer and liaison with tertiary facilities for research and local and overseas industry for new technologies and materials.
Before my days at Plessey Rola,
I joined Plessey when Plessey had acquired Rola and the loudspeaker division became known as Plessey Rola.
Regrettably I don’t know much about the Rola days that was before my time, but a lot of that product is still out there working. All I have are some of the Rola loudspeaker data books and adverts. Rola was a large company with a diverse product range, there was the Rola magnet division, Rola wire plant. At the Richmond premises they manufactured loudspeakers, Byer tape recorders, transformers TV yokes and TV components, vacuum encapsulated coils and transformers etc. I scanned some of the available Rola data which I kept.
The magnet, wire and press-shop plants were located at Harrisfield in Noble Park. The loudspeaker division was located the Company headquarters Richmond Victoria. This is a Rola advertisement in 1941, so the business was well established back then. Also these Rola products are the predecessors to or the origin for some of the Lorantz products., refer:
Rola G12 Loudspeaker made in 1948 (above).
We were fortunate to acquire this working example of a G12-Rola loudspeaker fitted with an F21 cone made 25th
Mar 1948, manufactured by Rola Co.,(Aust) Pty Ltd and we assume there were many models prior to this. So the
origins of our product go back a long way. The interesting feature of this loudspeaker were the patent No’s
applicable to this product: #5670/32, 10049/32, 10125/32, 14497/35, 16964/34, 18108/34, 18110/34,
101218//37, 110265/39, 112568/40, 116646 other patents pending. This suggests there was a very active and
innovative engineering department.
The Rola_data_book_1959 document includes a 1965 loudspeaker cone data sheet which detailed all the available cones types for Rola loudspeakers 8” to 12” diameter and their intended application for those interested. The model number was stamped on the spoke of the loudspeaker frame. The cone number was stamped in white ink on the rear face of the paper cone, when computers came into being the “F” part numbers became 5 digit computer numbers. The date of manufacture code is stamped on the rim of the loudspeaker rim the last two digit being the year of manufacture Brief review of good Plessey Rola days before 1975.
The origin of many Lorantz loudspeakers were built on successful Plessey Rola models, so it pertinent to look at the history. Plessey Rola was a large organization a fantastic company, cutting edge technology diverse manufacturing skills, the work was demanding. Plessey Rola had excellent toolmakers, press shop for producing speaker frames and magnet plant for production of both ferrite and alnico magnets, a loudspeaker cone production facility. A wire plant for wire production and highly skilled engineering department, diverse product range, get my drift. My first role was an R&D engineer with the group and I was appointed Loudspeaker design engineer for Plessey Rola in 1970. The work was challenging every day. In these good days Plessey were producing thousands of loudspeakers every day, at that time there was an abundance of work, and numerous electric guitar amplifier manufacturers, those I remember are Eminar, Goldentone, Phone, Savage, Strauss, Moody, Maton, Diason Etc. I took over as loudspeaker designer after Bill’s departure; Plessey had taken over Rola Loudspeaker division. Plessey Rola had two 12” electric guitar models the 12P and the premium model 12UEG, both being alnico models. I believe there may have been a connection between British Rola and Rola as there is a remarkable similarity between products, however if this was so it was well before my time. I arrived at conclusion based primarily on the close similarity as much of the tooling is similar to British Rola, (history goes back way before my time as speaker designer and I have no evidence to support this ). I concluded this only based on the remarkable similarity of speaker components and company names ie Rola Australia. Plessey Rola , British Rola and Rola Celestion. Was there a connection I am not sure if there was, if there was it was well before my time as loudspeaker designer at Plessey Rola, well before 1965?
Reference model tested at 20W rms cont at 200Hz (min impedance) for one hour without failure kept as a reference in our care.
Plessey Rola 12PEG Basic specifications:
This model was made with an F33cone nominal resonance 55Hz. This model was also available with F29 cone nominal resonance 75Hz. Both these models was discontinued and replaced with the C12P model.
Rola 12UEG (Laboratory 1960’s reference model) in my opinion the premium guitar model at that time. This is the OEM model (shown here) no magnet cover. This loudspeaker enjoyed a well established reputation in 1954 as World’s finest loudspeaker and in 1958. The 12UX is the twin-cone model.
This is the retail version Rola 12UX but the EG looks the same except for label. Premium Alnico Australian made loudspeaker in the 1960’s, in my opinion the premium guitar model at that time which we can still recone. This loudspeaker enjoyed a well established reputation.
The 12UEG is still a premium much sought after guitar loudspeaker and a real collector’s item, in my opinion one of Rola’s best guitar models. Available as bass model with an F20 cone having a resonance of 40Hz or the guitar model with an F31 cone having a resonance of 60Hz.
Basic Specifications for 12UEG data published 1961:
The evolution of the popular 2N3055/2N2955 50W transistor amplifier placed demands to upgrade the 12U model to handle 50Wrms. The spider platform was raised to accommodate the increased cone excursion; part of the alnico magnet was removed to permit greater inward travel without striking the magnet structure. The voice coil bobbin was increased in length which meant the coil winding was now further away from the cone. The coil winding was epoxy coated and oven baked to operate at elevated temperatures. This work preceded me, and laid the ground work for the higher power C12P loudspeaker.
The 12U50 was an excellent bass loudspeaker but the extra mass in the voice coil incurred a loss in top end efficiency and detail, hence I consider the 12UEG a better guitar model than the 12U50 (personal choice only). But the 12U50 is a better bass speaker than the 12UEG in my opinion. One must remember as the loudspeaker power handling is increased the bandwidth diminishes.
This model was also available with two different cones, you can distinguish between the models as follows:
12U50 MODEL was fitted with F19 cone or 12129 part number stamped on the back of the paper cone. If the cone is black then the cone is produces prior to the introduction of CFL cone technology. The model is stamped on the spoke of the loudspeaker frame the last digits being the impedance ie
12U52 MODEL was fitted with F20 cone or 12130 part number stamped on the back of the cone. If the cone is black then the cone is produces prior to the introduction of CFL cone technology. The model is stamped on the spoke of the loudspeaker frame the last digits being the impedance ie
When Plessey closed we made approx 2000 similar units in the 70’s identified as A308PA50 from surplus parts acquired from the closure, the guitar model was identified with a stamp stating “special guitar model”
Plessey C12P loudspeaker refurbished by Lorantz. Original
housing was Grey or Blue hammer tone baked enamel finish.
The Poseidon Nickel crisis in the late sixties pushed up the nickel price, a component of the alnico magnet to an uncompetitive level, customers chose ferrite magnet loudspeakers over alnico models as they offered better performance per dollar. The 12P alnico loudspeaker sales declined and at the same time the cone tooling was in need of replacement. It was then decided that to produce a new ferrite 12” loudspeaker called the C12P which was to be available in three models.
Unfortunately this model was so popular that this only unit we have as a reference. The demand was so high for
this model that production had difficulty meeting demand. The RRP price was $24.84 in 1974.
|Basic Specifications for C12P||Model||Model|
|Power Handling||30W rms||30W rms|
|Freq Response||35Hz-8 kHz||55 Hz-9 kHz|
|Impedance||8 ohm||8 ohm|
|DC resistance||6.9 ohm||6.9 ohm|
|Vas||206 litres||48 litres|
|Bl||9.7 T.m||9.7 T.m|
|Flux density||13,000 gauss||13,000 gauss|
|Weight||4lb 15 oz||4lb 15 oz|
You can distinguish between the models as follows:
The C12P model was fitted with F20 cone or 12130 (equivalent computer number) part number stamped on the back of the cone. If the cone is black then the cone was produces prior to the introduction of CFL cone technology. The model number was stamped on the spoke of the loudspeaker frame the last digits being the impedance ie
The last two digits on the rim of the frame is the date of manufacture which will be in range 1972-1975. The electric guitar model the C12PEG was fitted with F19 cone or 12129 (computer PN) part number stamped on the back of the cone in white ink. If the cone is black then the cone was produced prior to the introduction of CFL cone technology. The model number is stamped on the spoke of the loudspeaker frame the last digits being the impedance i.e.
The number on the rim of the frame is the date of manufacture range is 1972-1975 only last digit was used. The
above are the retail models however this does not define all the options which were available, numerous pulp
blends were available and special OEMmodels were produced for major customers.
I was responsible for designing and putting into production the C12P loudspeaker. The C12P could use the same cone options as the 12UEG and the efficiency was similar. It soon became a very important model an icon in the industry and found its proud place in locally manufactured HIFI, PA and guitar equipment. Tens of thousands were made each year.
Plessey Rola was one company which produced its own high quality cones from pulp and also sold cones.
A development project in conjunction with the CSIRO resulted in significant improvement in sonic quality, efficiency, bandwidth and reduced cone breakup, less distortion. Plessey speakers incorporating the new technique were identified under the term C.F.L. (Controlled Fiber Length). To distinguish cones made under the new technology the CFL cones were colored blue. In 1972 I was responsible for the introduction of C.F.L technology. This laid the ground work for testing and evaluating cone materials for enhancing sound quality.
As engineering manager I was saddened, disappointed and devastated to witness the closure of the loudspeaker manufacturing division which was an icon in the Australian audio industry. Plessey Rola ceased production of loudspeakers in Australia in 1975. Tariff protection had been significantly reduced ( a common practice today) with the result local manufacture of audio products and customers diminished, car manufactures opted for cheaper imported loudspeakers. Hence the demand for local manufactured speakers diminished making speaker production on the grand scale we were accustomed to was no longer viable. Is it good? Speakers today are much cheaper but it has come at a cost, our jobs.
My future was at crossroad I had spent most of my career in loudspeaker design; I had designing some very successful products but no longer had a paying job. I decided to have a go and purchased what tooling and parts I could afford from Plessey Rola to commence my own loudspeaker business, not blessed with money it had humble beginnings. I imported frames and magnets from Japan and commenced making the first Lorantz Loudspeakers in 1976 from available tooling in a garage.
The first Lorantz Guitar speakermodel C307PMI
Late 1970’s Lorantz Guitar model the C307PMI based around
the original Plessey C12P diaphragm. This is an original
prototype working reference model which we keep as a
reference to access aging properties of our loudspeakers.
Magnet assembly was similar, speaker frame was same depth but we made a buttercup spider to suit the new frame.
We made our own cone plant and refurbished the original 12UEG tooling, and so was reborn the Lorantz C307PMI loudspeaker.
For 1970’s data sheet C307P75/MI/8 We imported the best voice coil wire available at the time which had a temperature rating of 250°C which allowed us to upgrade the power rating from 30W to 50W; basically it was a 30W loudspeaker with a voice coil that could run hotter without failure. The success of adopting this new voice coil technology, building on the CFL technology established our reputation for making reliable great sounding loudspeakers. We quickly outgrew dad’s garage and relocated at the current factory.
Typical infinite baffle frequency response
of Lorantz C307P50-8 recorded at 2.83V at
1 meter B&K4133 microphone.
Measurements were sine sweep (nosmoothing) infinite baffle with purchased Ex Plessey General Radio chart recorder, Hemp pulp OFP cone body 1989.
The new high temperature voice coil technology meant our loudspeakers could comfortably handle twice the power rating without voice coil failure. In fact voice coils refused to fail, all the observed failures were attributed to mechanical failures, and we often observed that the paper edge had cracked fatigued and split. We had to improve the strength of an already optimized cone body. However we didn’t want to add anything to the base pulp which would significantly change the sonic signature of our loudspeakers. We had already established a reputation for making loud articulate loudspeakers from what we had learnt from CFL technology. Fortunately I had time and lots of different pulps. As I remember the hemp was picked up at a Magnavox auction in the 70s so I can’t claim to be the first to use it in cone production. I made cones from different pulps but the hemp cones were incredibly strong, nearly impossible to tear and sounded great. To my surprise when I optimized the Hemp pulp and added a small percentage to the base pulp the performance improved and from that time on we added Hemp to our pulp formulation in high power models to prevent cone stress failure.
Comparison Hemp cone (red curve)
and green curve without Hemp pulp.
The wiggles in the response below 1- kHz are attributed to boundary reflections in our test chamber which is used for comparison purposes only.
Comparative results are accurate but the spl is non anechoic.
Response of Hemp cone vs. non-Hemp cone, this response graph was recorded 80’s (no smoothing) using sine sweep recorder and includes boundary reflections. Note the higher top end efficiency and better control of the upper breakup modes. When I optimized the Hemp properties and added a small percentage our guitar pulp and wow the results were stunning, a strong durable cone with great detail and fantastic voicing qualities.
Want to read more about our optimized fiber properties (OFP cones) pulp technology.
The 12” electric guitar loudspeakers we make today are available in two ferrite magnet sizes “P” and “U” models.
C256P series having a 120 mm ferrite magnet and available in 30, 50 and 75 watt ratings
C304P series having a 120 mm ferrite magnet and available in 30, 50 and 75 watt ratings
C304U Series having a 147 mm ferrite magnet and available in 30, 50 and 75 watt ratings
C256P Guitar model C304P Guitar model C304U Guitar model
Current Lorantz range of guitar models the C256P, C304P employing 120mm ferrite magnet the C304U models employ the 147mm ferrite magnets.
The sonic quality of the 30W, 50W and 75 are similar, as these models employ similar cone tooling and cone pulps.
The 30W model is the brightest of the range it employs the lightest voice coil, the coil is wound on paper bobbin.
The paper bobbin has advantages and disadvantages. The paper bobbin is weak and allows the cone to breakup more than the stronger bobbins like fiberglass and Kapton. Paper bobbin can’t handle much heat hence the low paper rating even though the wire employed has a higher temperature rating than the bobbin. The paper bobbins don’t like high humidity as moisture greatly weakens the paper strength. The paper bobbins are known to shrink deform with heat and humidity and were replaced with Nomex and fiber glass in the 70’s due to their superior reliability higher power rating not necessarily better sonic performance. There appears to be a price or pain for everything good.
The 50W model is very similar to the 30W except the paper voice coil bobbin has been replaced with fiberglass, higher power rating and environmentally more reliable than paper. The cone body is also slightly heavier thus requiring more power for breakup and crunch. The 75 W model employs a heavier cone body again requires more power to breakup, also has a longer coil winding so its cleaner and the tone is slightly warmer due to the heavier coil and cone body. The coil is wound on a high temperature plastic bobbin material called Kapton.
The sonic signature of loudspeakers is primarily based on the physical cone shape and material properties. As the shape is similar to Rola Celestion we immediately acquire some prime characteristics. However our intention has always been to create a unique Australian sound. If you like the Celestion sound you should purchase a Celestion loudspeaker you are then 100% assured of a Celestion sound.
Primarily the sonic differences between our guitar loudspeakers and Celestion are the cone paper formulation.
Paper pulp has seen some radical changes in recent times. We are no longer permitted to cut down 300 year old trees to make paper pulp or for that matter guitar bodies. Hence all speaker manufacturers today are struggling to reproduce the paper quality derived from 300 year old trees when good wood was plentiful; today we use regrowth forest where the average tree age is 5-10 years. Many of the solvents lacquers employed in the past have also been discontinued as they were environmentally nasty or casnagenic. Paper cone material matching is a problem today, for all loudspeaker manufacturers as paper quality is a vital ingredient. It’s an art form just as important as making musical instruments, it’s part of the musicality. That is basically why the vintage gear is collectable, even though the engineering often was not that great, it’s part of our evolution, and you don’t miss it till it’s gone.
Plessey Rola initiated a research program in conjunction with CSIRO to use Australian pulp I implemented CFL (control fiber length) into cone production at Plessey Rola in the 70’s and this pulp formulation was used in guitar cones at that time without hemp. Late seventies at Lorantz I added Hemp pulp to the guitar cones to prevent surround fatigue as the power ratings. These failure issues were the result of higher amplifier powers being available and guitarists playing with more bass than in the past, resulting in the cone surround splitting fatiguing.
Our paper pulp formulation has now been implemented and recognized world-wide. Due to the high tariff protection prior to the 70’s our renown musicians could not afford imported gear and cut their teeth and derived
their fame with local manufactured gear. that’s how they evolved, they were unique.
Getting back to old days the70’s when I designed and fine tuned many guitar loudspeakers for local manufacturers at Plessey there is no one guitar loudspeaker that will suit all amplifiers. Where the standard model didn’t cut it often the guitar loudspeakers were modified to achieve the desired tone, I don’t see too much of that happing today as the local guitar amplifier business has gone small and boutique. Loudspeaker manufacturers are not interested in small business they are forced to rationalize their product range to survive or increase profits, so unfortunately today you have to find a guitar loudspeaker that works well with your gear that is the nature of business today.
Based on your feedback we strive to make to make the best Guitar loudspeaker possible however I have never found the wholly grail where one model suits all, I don’t believe such a thing exists for the same reason there is such a choice of beers and wines.
The principle difference between the "P" and the "U" models is the magnet size. The increased magnet size has the following sonic benefits:
(a) The U model is louder
(b) The bass response in the “U” range is tighter.
(c) The mids appear louder as the bass is more damped and tighter and mids are relative to the bass level.
(d) The tone is more detailed as the voiceoil now follows the electrical signal much better due to the stronger magnet force, so you are in control, ie the speaker hides less or more dtail.
Basically, these models sound more like Celestion’s modern re-issue of the Vintage Greenback, whereas Melmusic’s models sound exactly like (within 1 dB!) a real vintage Celestion Greenback.
The “U” model would be more suited to a Jazz player using say, a Roland JC120, or the player wanting to get that slick American “Toto” kind of sound, IMHO.
Lorantz Spec/Data Sheets listed HERE