Saturday, October 30, 2010

Leak Delta 30

The Delta 30 was created from the Stereo 30+ with minor modifications e.g including 2 capacitors added for the earphone socket based on schematics found on the internet comparing agianst what I could make out after reviewing the internals at a glance.

Though sporting a lowly 15W RMS per channel, it packs "quite a kick". Like all Leaks, the Delta 30 is a musical amp, with clearity to match.

Was throughly surprised at how well it partners the Technics SB-X700 (after "iso" features added)!

The Delta 30 has the following inputs, with TUNER1 for microphone connectivity via RCA. There are LOW-HIGH gain selectors for DISC1 (aka phono) and TUNER1. My Delta 30 is multi-voltage capable as well.
Speaker connectivity are via a pair of 2-pin DIN connectors. Such DIN connectors are normally use by B&O units (next pix). On the corners of the previous pix, label speaker output is for LEFT, B is RIGHT. The round pin is +ve and the flat connector is -ve.
2-pin DIN speaker connector

The next pix shows the unit once removed from the wooden casing.
Without wooden casing
And after removal of the black plate...
Internals from top


  1. I have one of these which I have repaired and am now restoring. I didn't think much of it at first but it has really grown on me. I was lucky and got some Sandwich 150 speakers with it. It's hooked up to a PC and A half decent CD player. I use it for for radio and teaching English (I am in Japan)
    Yours looks in excellent condition, mine is a bit more knocked about.
    Are those red coupling capacitors original or have they been replaced at some point? Mine are blue. It's a worthwhile move if so. I'll be doing mine in the next week or so.
    In the unlikely event you want to connect a mic you have to cut the two white wires on the selector switch. HiFi was still pretty DIY in those days. The owners manual contains a load of service information as well as circuit diagrams.

  2. Hi Gareth,

    All the capacitors are original parts. Quality in those days really meant something.

    Only item changed was the transistor which failed on the LEFT channel. The shop which did the repairs took about 6-months to locate an original part to complete the job!!!

    The Delta 30 really matches well with the Musical Fidelity Tubalog.

    1. Hi. Wonder if you could shed light on the problem I have got on my Delta 30 Amp. When I turn amp on and play music through it the signal in the right channel is distorted and quickly fades away. I have swapped over the left pre amp board to check that it is definitely a fault from one of the components on the right pre amp board, maybe a capacitor. Any suggestions please, and also where I may be able to obtain them as Maplin dont seem to stock these 68mf capacitors. Many Thanks Brian.

    2. Hi Brian,

      You can try the large suppliers eg element14, rs-components but these may have a minimum purchase amount. Alternatively eBay. If you can't obtain axial, can consider the normal radial - need to bend it so require longer leads for adjustment (would help to put the leads into insulators of sorts). If so, maybe necessary to do both boards to ensure the reproduction remains centered.

    3. Thank you. I have ordered some 100mf 100v Capacitors from an electronics website as these were the nearest values that they had. I was after 68mf 68volts hope these different value components will sound ok.

    4. Hi Brian,

      I just checked element14 and they have a variety of 68uF 100V. Let me know if you require assistance in the matter. Or perhaps another reader can assist if they are in your region of the world - which country are you residing?

    5. Yes. Thank you, I have done like you said and contacted element14 and they have come back with the same advice as yourself. I live in wild west Wales, ie Pembrokeshire. I really appreciate your help.

  3. That is impressive and as you say the build quality and the quality of the components is very good. I also had a problem with the left channel not working. In my case I can't send it to a shop but some very kind people on the internet guided me through tracking the problem to an failed resistor in the preamp board. A very cheap repair that one in the end.

    I am running it 8 hours a day or so and it seems the electro capacitors are starting to go. One in the preamp boards went about two weeks ago and yesterday the one of the couplers finally submitted. 35 years is a pretty good innings but they are on their last legs now. They are pretty easy to change thanks to the modular design so bit by bit it's being recapped as it develops another fault. Once that is done I think it will run for another good long time.

  4. Have since sold the Delta 30 to make room for the Stereo 30 Plus