Guitar Output Transformers

It is all about tone.

The output transformer is a crucial and vital part of the guitar amplifier. The tonal quality of the electric guitar will never be better than the characteristic properties of the output transformer.
It really is as simple as that.

Lilienthal guitar transformers is made in a close cooperation between passionated musicians and dedicated engineers. The guitar players has the first and final word here.

2k:2,4,8Ω, 100W
4 x EL34, 4 x KT88/6550

May be used for JMP, JCM 800, CM 900, Dual Showman, Twin Reverb and many more
3k2:4,8,16Ω , 50W
6L6, EL34
May be used for JMP, CM 800 etc.
4k:2,4,8,16Ω , 50W
6L6, 2A3, 300B,
May be used for AC30, Bassman, Deluxe, Deluxe Reverb, Super Reverb, Tweed Bassman etc.
EL34, KT66, 6L6, 807,
7-8k:4,8  Ω , 20W
EL84, 6V6,
May be used for Blues Junior, Reverb, Tweed Deluxe etc.

2k5, 15W
6L6, KT66*, 2A3, 300B
5k, 15W
6L6, KT66, 6V6, EL84, 300B


Guitar OPT ( Output transformer )  are normally made by the use of laminates in the shapes of E and I.( While writing this Lilienthal Eng. is the only company known to us that does not use EI laminates for guitar OPT )
The common metal used are Silicon Steel, which comes in dozens of qualities. Some of these are very cheap. The best ones are known as Cold Rolled Grain Oriented Steel (GRGOSS ) These are also available in a varity of qualities and prices.
Transformers made of laminated EI, apart from being the cheapest possible, posseses a number of disadvantages.These are avoided by the use of the more expensive C-cores.
All Lilienthal Eng. guitar output transformers are made by single or double loop C-cores.  In order to obtain the best possible tone quality, we only use the best available GRGOSS and other advanced metals.( Nickel, Amorphous etc. )

How are guitar transformers different from HiFi transformers ?

Well, in principle they are not. The same basic calculations and techniques are used*. But in several ways the qualities and properties you wish for in a guitar transformer differ vastly from those you look for in a HiFi transformer. A HiFi transformer needs to be as neutral as possible. It must add nothing and detract nothing. Consider it as a glass window. It must be as clear and transparent as possible in order to expose a full and clear view to the musical stage. In other words a HiFi transformer should not add a personal signature. The “personality” of a HiFi transformer is indeed that it has no signature. In short: No distortion. It must remain linear at all times and is not allowed to interpret the music signals.

Guitars on the other hand are musical instruments and the tone quality and timbre is quintessential. Here we do need to express personality and characters.The transformer in a guitar amplifier must respond to the signals, the touch and play of the musician. We need it to “talk and sing”. A guitar amplifier must be touch sensitive in order to respond to the musical articulation as intended by the musician. This ability is achieved in the combination between the design of the valve circuit and the merrits of the transformer.

The “glass window” in a good guitar transformer allows the musician to add the colours he likes.The manner in which the transformer handles the complex harmonics of the guitar, plays a major role as we express ourselves in that advanced language called Music. A poor transformer will mask the personality of the guitar player as well as the specific tonal quality of the guitar, pick ups, amplifier circuit, valves and speakers. Guitar amplifiers drive the output transformer in manners that will never happen in a HiFi set up. ( Well – if it does, you are in trouble ! )

Distortion and excessive overdrive are part of the sound marks of electric guitars, and this fact demands for quite special skills from the output transformer. Technically the dynamic linearity of a guitar transformer is different from a HiFi transformer. Certain alloys sound better than others, and certain annealing of the core tapes are better than others and so on.

(* parts of the mathematical formulas used to compute transformers, must be altered due to the nature of electric guitar signals. Also the winding technique and materials have to be selected to this specific task, if the best performance is the goal.)

Nobody knows exactly how to measure the quality of a guitar amplifier. Lilienthal Engineering rely on extensive listening tests and the feedback from experienced guitar players when developing our guitar transformers. The musician has the final word with regards to guitar transformers in our company.

Can a HiFi output transformer be used for guitars and vice versa ?

Well, it is possible to use a HiFi transformer for guitar, but it is very very unlikely that you will become satisfied with the results. You will find it cold, harsh and less articulated or inclined to express the musical timbre. Yet, as a matter of fact, some few people actually prefers this notation in sound as part of their musical language.

Using a guitar output transformer for HiFi is a bad idea, if you want high quality.
Apart from the fact that a guitar transformer would be way to small (Power and core size ) it is designed to cover the frequency range from a guitar and it can not handle the range necassary for High Fidelity. We will experience a relatively narrow frequency range, less low freq power, more colouration and as a consequence more distortion.In less words “Lo Fidelity” 

We make three types of guitar transformers, based on the sonic quality. As we have no objective vocabulary for specific sound characteristics we have marked these with the tempered notations of: “Neutral”, “Medium” and “Hot”. Please, remember that these are only subjective words.

Hot is likely to be used for blues, Jazz or expressive instrument voice.

Medium warm used for classic rock guitar in all its colours.

Neutral for clean, tight harmonics or heavy. ( Excessive use of distortion pedals )

However, In the end, what type of output transformer you prefer is all a matter of personal taste and preference. It depends on your own subjective musical expression, the style of your playing and not least the amplifier circuit, the specific power valves, speakers, guitar and pick ups. All types of our guitar transformers will sound like you have a bigger and more open amplifier, compared to most others transformers. More tone, tighter and punchier low end, more plastic deeps and highs, better dynamics and more details. This is not a bad swap.

Finally an important note of technical advice. As our range of guitar transformers usually have lower losses and a broader freq response, in other words more highs and lows and quite better dynamics, a direct swap from a traditional or standard quality transformer may in some cases present a problem with regards to the global negative feedback loop and/or the tonepack. If you experience a harsh or hard top, this is because a better transformer allows more electronic feedback. ( Not to be confused with acoustic feedback ) In order to correct this, please reduce the NFB. ( Higher resistor and/or smaller capacitor ) If in doubt , please consult your local worksshop or contact us with the informations on the actual amplifier and transformer. We will be happy to help you. In case of “motorboating” a continuous low frequency pulse that sounds similar to an old motorboat, swap the two anode connections from the output transformers to the two power valves.

Enough said. We all claim we make the best transformers, dont we…? I will let you be the judge. You do not need to buy our transformer. You can hire a few and decide it for yourself.

Evaluation kits:

You can order three transformers of your choice as a kit for experimentations. This will be done at the basis of hire/rent. You will need to pay for the shipping in full, both ways, and a fee at a weekly basis and a deposit of the value of the transformers. The final rent price has not yet been decided while writing this. After max 3 month of hire, unless other agreement has been discussed the hire will be cancelled and the full fee will be charged. At this point we consider it as a final sale. The transformers you can hire in this kit are likely to have been used by other customers. Hence they may show signs of use in form of scratches and so on. If you decide to purchase any of the transformers you may keep the one you choose or return them all to us, in which case you will receive a new unused item of the transformer you have picked.

Why do we charge a fee for this service ? Well, we can not make a living from transformer hire and we must use labour to pack and send these and upon return we need to carry out a full test program to make certain that the transformers are perfectly all right and undamaged.

We offer unlimited guarantee on our guitar transformers, except in the case of open ( burned ) primary winding, as this can ONLY happen in the case of amplifier error, such as a short circuit or similar. In case of a defective Lilienthal guitar output transformer, please ship it to us and if it is indeed an error on our side we will provide you with a new transformer at no cost.

The most common valves in guitar amplifiers are 6V6GT, EL84, 6L6GC, EL34, KT66 and KT88/6550. But really almost any valve will make good guitar amplifiers, and most certainly the traditional valves are not in any way the best. They were chosen at the period only due to price and availability.

Type code: H = Hot, M = Medium, N = Neutral

A matter of WARNING.

Valve amplifiers maintain high Voltage of lethal nature. It is not a job for the untrained amateur to replace the transformers in such devices. Please, leave that to qualified personnel at your local guitar workshop.


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