If it looks goods, which it does, and sounds good, as you say it does, that’s great! Now just enjoy the music! For goodness sake not Slade’s “Happy Christmas Everybody”! Happy Christmas Barrie to you and your family!
Finally got round to sorting the TT earthing issue I was getting quite a loud hum when TT was selected on the AIWA pre amp. I resolved it initially by introducing a small Behringer graphic equaliser between the pre amp and power amp. By careful selection, I have been able to reduce this significantly. However, it wasn’t solving the problem. Neither the LEAK TT or the four AIWA components are earthed, just live and neutral plugs into mains. The TT is earthed to the pre amp but that itself is only using its chassis as an earth, which I presumed was the issue. Anyway, acting on advice from Roadie I rigged up a 3 pin plug with just the earth pin connected to the GND terminal on the pre amp, along with theTT ground lead. This has now made the output signal, hum free!! It’s the best it’s ever been, I’m really happy with this outcome and apart from the two crimp rings and the plug/earth cable (modified from a redundant plug and cable from a disfunctional appliance and some heat shrink tube) was a zero cost, massive improvement to my enjoyment of listening to my old vinyls
For some reason, although my pics are the correct orientation, when put on postimage they are reversed and upside down? You get the idea anyway
Cartridge on the turntable gives a much lower output than CD / Tape / Tuner line level signals so more prone to picking up any interference. Also it uses a coil to generate the signal which is perfect for picking up any stray mains field floating around. Got to be mains in the deck to power the motor so that’s where the problem comes from. Earthing the chassis of the deck will improve things no end. If it isn’t earthed it will effectively act as an aerial to pick up the hum. That’s why there’s a wire to connect it to the amp chassis. Problem is that if that’s not earthed you just have an even bigger aerial. Hence why the extra wire to a real earth does the trick.
A quick browse on Facebook marketplace, after posting on here, produced this, a sound style HIFI stand, or at least the same model (library picture) mines in dark green with marble effect shelving.
There is one glass shelf missing unfortunately but it was free and 10 minutes from my house it’s back home now in the garage! I’ll swap the top shelf to a lower position and replace that with one of several, slightly larger glass shelves I have, to sit the a turntable on. A great day so far!
Hiya, hope you’re keeping well? Yes, must admit, I’m enjoying this stuff now probably more than I did back in the day! It’s less expensive and nice to search stuff out, a quick refurb and off you go! Current collection points for some of this varies between Redbourne, Upminster, Nelson, Mansfield, Nottingham, Bristol, Stafford, Bradford and many other places I’ve forgotten! Gets me a drive out though in the 5 and less risk of damage.
I remember having an annoying “hum” when I first got my Garrard/SME/Shure set-up many decades ago. TT has 2 core power lead and there’s a separate terminal on the chassis for an earth which I duly connected to the earth terminal on the amp and when I switched on…“HHHHMMMMMMMMMMMMMMMMMM”. It then dawned on me that as the Cartridge/pick-up was connected to the amp via a 5 pin Din plug there was also an earth connection there, so what I was getting was an earth “Loop” so I disconnected the earth between the TT chassis and the amp and…SILENCE!
Whether the deck is connected to the amp via RCA (phono) or DIN connectors there will be screened cable. It would appear that in Roger’s set up the screen was connected to the chassis of the turntable so an earth connection between TT and amp was made that way. An extra cable would indeed create a ‘hum loop’.
Now this isn’t the ideal situation. Any stray earth currents flowing down the screen could be picked up via the signal wires. Ideally a screen should only be earthed at one end so there can be no current flow. This is highly unlikely to create any problems with line level signals as there is a high signal to noise ratio. Signal to noise ratio is much lower on a magnetic cartridge signal.
So the ideal setup is to earth the amp chassis and then add the continuity wire to the TT chassis. Then the connection from cartridge to amp only picks up an earth for the screen from the amp connection.
If you get any hum on other system components it will probably be due to poor quality cables. The outer screen on these cables should be just that, a screen. Too few strands in the screen and interference will get through. Quite often just moving wires around will do the trick. Plenty of times I’ve tidied up cables only to find I’m getting hum because there’s a signal cable too close to a mains cable.
Thanks Paul! When I’ve got the above mentioned TT/pick-up combo out, and before I use it again I’ll have all the wiring/connections etc checked by my nephew who’s a qualified electrician!
I’ve just been looking at my other TT unit, Rega P7, and it has the same wiring set-up as the Garrard/Shure/SME one. It comes supplied with twin core power lead and two heavily screened leads/RCA plugs from p/u to amp. Maybe this sort of wiring set-up is more common with TT/pu units than was thought. Anyone else checked theirs to see what’s what?
I believe my LEAK 3001 had a DIN socket as standard. This has been converted to twin hardwired RCA phono leads that plug directly into my AIWA pre amp. I much prefer RCA sockets on the rear of the TT, that way you can “upgrade” the leads to match the other interconnects on the system. Without looking, I think the DELTA 75 amp/receivers I have, are DIN input socket for TT, so RCA to DIN adapter required. I’m certain that the illustrious member on here who passed on the amp to me, included just such a thing! Having said all that, I used the AIWA system for long enough with the original basic interconnects (white unscreened cables with red and white moulded plugs at either end) and didn’t notice a massive difference when I replaced with the thicker, screened, gold plated affairs that I now use although they do look nice!
Barrie
EDIT: always best to look at the manual I was right about the DIN plug/socket but was actually on a lead as is the RCA lead currently installed, with a separate earth lead.
I much prefer RCA type plugs but I do understand that multi pin DIN type plugs can be useful, and they have a good, snug fit in the socket, however there is absolutely no saving grace whatever for DIN speaker plugs! They are an absolute waste of time and space with a propensity to come out of the socket if a remotely decent speaker cable is used thus putting the amp at risk!
Not quite sure what you mean by that Paul but surely RCA/Banana plugs and sockets are colour coded to prevent mis-matching, and so is proper speaker cable to prevent wiring errors. So I still can’t see any “Pro” for DIN speaker plugs/sockets. Have I missed something?
Hi Roger,sorry for butting in here but I think Paul is referring to the 2 pin speaker plug as one terminal is a flat blade, the other a round pin? That way you can’t plug it in the wrong way? Hopefully the cable will match the plugs at both ends
Barrie
Ive just bought some of these, rather than the round type, not tried them yet though.
Hi Barrie. That’s very true but you can’t plug in a correctly wired RCA plug the wrong way round either can you, just make sure that the same wire is connected to the same terminal in the plugs at either end?!? So no “Pro”?!?
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