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http://www.eurotubes.com :
Hi Alberto-
Engl typically uses Chinese tubes in their amps. Most Chinese tubes have a flabby, boomy low end, a harsh cardboard like midrange and a very shrill and brittle high end. When they distort they are not smooth they are very hairy and grainy. The JJ Electronic tubes in contrast are very linear tubes which allows your EQ to respond more like it should. They have a deep, tight low end, a natural and harmonically rich mid and a sweet high end with a nice sparkle. The JJ tubes overall are very smooth with a lot of detail so there is quite a difference.
The Engl 530 preamps use a pair of 12AX7’s so we typically use two of the matched triode JJ ECC83S’s which will maintain the amount of distortion the unit has. For a real high gain application we use two of the graded high gain JJ ECC83S's that are between 105+ in gain. These will still get a good clean but they will get you maximum gain and definition.
The matched triode ECC83S’s, the gold pin ECC83S’s and the high gain ECC83S’s are all available in the online store.
A pair of the matched triode ECC83S’s would run 25.00. A pair of the high gain JJ ECC83S preamp tubes would run 32.00. A pair of the matched triode gold pin ECC83S’s would run 46.00.
Your Engl E840 power amp uses a quad of 6L6’s and three 12AX7's so I would use three of the JJ ECC83S preamp tubes that are a matched and balanced set and for the power section a matched quad of the JJ 6L6GC’s will do it. These will get a deeper and tighter low end and a less harsh and brittle tone than the stock tubes
A full retube with a matched quad of the JJ 6L6GC’s and three matched and balanced ECC83S's would run 117.00, and we can ship them for 9.00 to 13.50 depending on your location, by Priority mail with a 3 day delivery anywhere in the US.
If you decide to place an order you can do so online here:
https://ssl.eurotubes.com/cart/
This is a certified secure system, but please don't feel obligated to order online you are always welcome to just give us a call at 503-659-7401 during business hours which are from 9AM to 5:30PM west coast time to place an order personally.
Let me know if you have any other questions.
Por cierto, cuánto cuesta cambiarlas y cuanto se suele tardar? todo aproximado claro.
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