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Open Door
12-09-2019, 23:08
MP EL84 Principino class A valve amplifier

Link here- hand made in Italy, super rare (interesting website):
http://www.mpamplificatorivalvolari.it/push-pull-el-84

One for sale is an older version by the look of the internals and valve locations. Mine has some decent upgrades as mentioned below.

According to their website:
Ultra-linear Push-Pull with EL84 class A
Based on the LEAK 20 schematic
15W output 8 ohms
10Hz-30Khz frequency response
Bartolucci transformers (supposed to be very good and specifically designed for this circuit)

Amp has superb bass and slam. Lovely sweet sound, very revealing.
Upgrades to this unit:
1) Coupling caps are Mundorf ZN and RelCap Teflon/tin - very expensive
2) Binding posts by Jensen
3) RCA’s by CMC but with a true 24ct gold plate (soft, not hard plated with nickel)
4) IEC is a ACME Audio silver plated type and cryo treated
5) Selector switch is now an Elma type with gold pins
6) Rectifier tube is supposedly a high spec 5U4G from the Soviet Military, which I imported from the US of all places.

Bad bits:
Some blemishes to the light oak chassis - still looks amazing though.
Amp comes with no bottom cover (comes like this). Just means one could grab the amp from underneath and get a nice shock. I’ve avoided it but just so you are aware.
While the amp sounds amazing, it is not the quietest amp I’ve come across (low noise speaker hum as with some tube gear). But once the bass starts kicking and highs do their sparkling trick, it is more than forgiven ��
Selector switch moves to 3 locations but there are only 2 inputs. Selector switch can be removed and the plug moved to accommodate this but I’ve been lazy and it never bothered me.

Bespoke well made packaging for it (but just a box). Tubes have low hours, maybe 120 hours on them.

Collection with demo preferred but I will post.

Priced to sell. I’ve got a valve pre and power combo as well as a new amp on the way so this amp will get little use now - needs must. A lovely and very rare piece.

£750 incl post. £730 collected.
These retail for 1995 Euro.

https://i1279.photobucket.com/albums/y535/Dizarden/EDC63032-DC3F-4DB1-97E5-DBA1E29DE65D_zpsytu9n5dx.jpeg (http://s1279.photobucket.com/user/Dizarden/media/EDC63032-DC3F-4DB1-97E5-DBA1E29DE65D_zpsytu9n5dx.jpeg.html)
https://i1279.photobucket.com/albums/y535/Dizarden/E5F51275-9A58-467D-8E51-D1502B32B82F_zpsl9c2eckx.jpeg (http://s1279.photobucket.com/user/Dizarden/media/E5F51275-9A58-467D-8E51-D1502B32B82F_zpsl9c2eckx.jpeg.html)
https://i1279.photobucket.com/albums/y535/Dizarden/9EDA7EFA-F2C2-46A2-BC39-C00C05A70E83_zpsuv5knnfl.jpeg (http://s1279.photobucket.com/user/Dizarden/media/9EDA7EFA-F2C2-46A2-BC39-C00C05A70E83_zpsuv5knnfl.jpeg.html)
https://i1279.photobucket.com/albums/y535/Dizarden/046BF022-2F2E-4010-A803-D4872042887D_zpsyoi1hsz1.jpeg (http://s1279.photobucket.com/user/Dizarden/media/046BF022-2F2E-4010-A803-D4872042887D_zpsyoi1hsz1.jpeg.html)
https://i1279.photobucket.com/albums/y535/Dizarden/3A80A4AE-0BD2-4B1D-8E39-FF96B983F935_zpsdcfuklai.jpeg (http://s1279.photobucket.com/user/Dizarden/media/3A80A4AE-0BD2-4B1D-8E39-FF96B983F935_zpsdcfuklai.jpeg.html)
https://i1279.photobucket.com/albums/y535/Dizarden/E3AC2B29-6F81-4161-A706-F96A746941F5_zpsqnyvwczo.jpeg (http://s1279.photobucket.com/user/Dizarden/media/E3AC2B29-6F81-4161-A706-F96A746941F5_zpsqnyvwczo.jpeg.html)
https://i1279.photobucket.com/albums/y535/Dizarden/0D920A59-3718-4E8E-8190-8BC37680C17E_zpsvoirhctl.jpeg (http://s1279.photobucket.com/user/Dizarden/media/0D920A59-3718-4E8E-8190-8BC37680C17E_zpsvoirhctl.jpeg.html)

Stormin'Norman
13-09-2019, 19:11
Hi, quick question. Current model appears to use Blue Alps, could you clarify what fulfills this role in the one you have for sale ?
Thanks, Norman

Sent from my SM-G390F using Tapatalk

Open Door
13-09-2019, 21:05
It has an Alpha pot.
Pot casing is linked to the grounding circuit so not sure another pot can be used (shielding).

Pharos
13-09-2019, 21:45
Having built numerous similar amps in the 70s, and gained a reputation for building 'no noise' amps, I think a little tidying up and maybe judicious application of screening could possibly reduce that.

The 'carve marks will probably be obscured with a little polyurethane varnish.

Kneesup
14-09-2019, 00:04
Knowing Robert very well, he will always describe every flaw, however tiny. He is a very generous and kind authority who if anything will make an item sound worse than it really is. So anyone interested can buy with total confidence and with the assurance that any flaws described will probably be very hard to spot.

Open Door
14-09-2019, 15:47
Let’s male it appealing ��

If unsure or tempted, bring your speakers around to demo.

£600

Stormin'Norman
15-09-2019, 09:47
Morning Robert, am giving a bit of thought to this amp. Need a little bit more info, what makes of valves are currently fitted and what finish is the metal body, brushed stainless; polished stainless etc
Thanks, Norman

Sent from my SM-G390F using Tapatalk

Open Door
15-09-2019, 10:21
Hi Norman

Tubes are:
New issue Sovtek EL84’s (x4)
3x new issue Sovtek 7025 / 12AX7

I’ll include a Pearl Tube Cooler / Dampener for the preamp tube.

Finish, is stainless steel, more brushed than polished. Sort of a dull finish. I’ve tried to take a photo as below.

https://i1279.photobucket.com/albums/y535/Dizarden/049FFBC8-3B96-42AD-9998-91EB1F64867D_zpscgv0un7u.jpeg (http://s1279.photobucket.com/user/Dizarden/media/049FFBC8-3B96-42AD-9998-91EB1F64867D_zpscgv0un7u.jpeg.html)

https://i1279.photobucket.com/albums/y535/Dizarden/C21DD940-4A03-424E-9FAA-BDFCC1FF8435_zps44wenhhg.jpeg (http://s1279.photobucket.com/user/Dizarden/media/C21DD940-4A03-424E-9FAA-BDFCC1FF8435_zps44wenhhg.jpeg.html)



Morning Robert, am giving a bit of thought to this amp. Need a little bit more info, what makes of valves are currently fitted and what finish is the metal body, brushed stainless; polished stainless etc
Thanks, Norman

Sent from my SM-G390F using Tapatalk

jandl100
15-09-2019, 17:28
Oooo, I love el84 amps. But I already have one.
My favourite power tube, so natural, just yummy. :)

GLWS.

Stormin'Norman
16-09-2019, 14:21
One more question ! On the schematic posted on manufacturer's web site it shows 3 trappings possible to suit speaker impedance. It's not immediately clear how to do this as wiring pics are quite different, any info appreciated because my speakers would need 4 Ohm tap.
Regards
Norman

Sent from my SM-G390F using Tapatalk

Open Door
16-09-2019, 23:20
Responded via PM


One more question ! On the schematic posted on manufacturer's web site it shows 3 trappings possible to suit speaker impedance. It's not immediately clear how to do this as wiring pics are quite different, any info appreciated because my speakers would need 4 Ohm tap.
Regards
Norman

Sent from my SM-G390F using Tapatalk

Open Door
26-09-2019, 21:42
Still for sale.

Amp sounds epic! It is quiet, just not spookily though.
Very dynamic, detailed and superb bass attack. I have another amp here at twice it’s price and they are on par. But keeping the other due to the remote control functionality, tube swaps capability and extra power. But shocked how it is not better.

I’ve added a rubber boot to the fuse holder and also a perforated aluminium bottoms cover so fingers can’t go prying
near live wires ��

Still for sale - sadly.

Open Door
30-09-2019, 11:59
Sold