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Leak TL which decoder?

Maybe I have access to too much test equipment and have spent a lot of my career with VCOs and PLLs. They do improve with care, how far is overkill is debatable.
The lead network is what I meant, it has to match the tuner group delay.

Agreed on that, much better than the MC1310. Pilot tone cancellation means no nasty notch filter needed

We are only talking about a 76KHz oscillator here... not GHz!:)
 
Only 76 kHz on a crude VCO and rather dumb PLL. I am not aware of any tests on how pilot carrier recovery "jitter", due to multipath, adjacent channel interference and so on affects stereo image especially.
I have only heard a few good tuners, notably Creek and they do get a much better image.
These days I don't have access to a good source like R3, Malaysian stations are very poor technically.
 
Have you read the Noel Keywood review (HiFi World) on our "G T Audio Restored" Troughline? It was their reference tuner for many many years and as far as I know it is still mentioned in their magazine. During the 1990s and early 2000s we got hundreds of these tuners in to restore update and fit stereo decoders too. My records show we restored at least 600 and owners were extremely pleased with them. We even used to get HiFi shops asking us to restore them too. I compared our version of the Troughline to all the top American tuners from the 1960s/70s, i.e. from Marantz, Fisher, McIntosh and Scott (I owned all of their top models as well as the CT7000 from Yamaha) and the Troughline was not quite as good as the US made tuners but it was significantly more simple and not that far behind in the sound quality stakes. We even developed a special stereo decoder for the Troughline using a modern Philips decoder chip which fitted inside the chassis and that worked very well. Even Tim de Paravicini must have thought the Troughlines was good otherwise he wouldn't have bothered developing a special stereo decoder for it either...

Someone has just snatched the One Thing Audio Decoder before me, at the auction site.
Looks like no one is making the decoders for the Leak 2 these days.
Even from the dipole antenna (indoors), the sound is unlike other tuners (I do own one german valve tuner), the only problem with my Leak 2, soundwise ( apart from the low-ish level of the output, but that is another subject) is the flabby and overblown bass.

And this is (bass response) is a huge problem to me; I have no idea why it occurs and how this is rectified.

@G T Audio , @Arkless Electronics - do you stil make any of the decoders for this tuner?
 
Someone has just snatched the One Thing Audio Decoder before me, at the auction site.
Looks like no one is making the decoders for the Leak 2 these days.
Even from the dipole antenna (indoors), the sound is unlike other tuners (I do own one german valve tuner), the only problem with my Leak 2, soundwise ( apart from the low-ish level of the output, but that is another subject) is the flabby and overblown bass.

And this is (bass response) is a huge problem to me; I have no idea why it occurs and how this is rectified.

@G T Audio , @Arkless Electronics - do you stil make any of the decoders for this tuner?

If you can find one second hand the Tim de Paravicini decoder I have on my TL stereo rewired by TdP as it had no multiplex out normally would use/plug in to the multiplex socket, works brilliantly despite what some of the curmudgeons on this site usually say...
 
Someone has just snatched the One Thing Audio Decoder before me, at the auction site.
Looks like no one is making the decoders for the Leak 2 these days.
Even from the dipole antenna (indoors), the sound is unlike other tuners (I do own one german valve tuner), the only problem with my Leak 2, soundwise ( apart from the low-ish level of the output, but that is another subject) is the flabby and overblown bass.

And this is (bass response) is a huge problem to me; I have no idea why it occurs and how this is rectified.

@G T Audio , @Arkless Electronics - do you stil make any of the decoders for this tuner?

I never made decoders as a commercial enterprise... just loads of different ones for my own use .
If all my comments about these tuners actually not being very good in stereo can't put you off then I could build you one as a one off but if you need to ask what it would cost... I will likely have several I made 20 years ago but they will be just the actual decoder and need power supply and amplifiers/buffers before and after the board plus pilot tone filter etc so not much help. In total probably £400+ for me to make you one from scratch and would come with a guarantee that the combination of Troughline 2 and decoder will sound poor... I have about a dozen Troughlines... there's a reason I use modern tuners and internet radio instead ... they sound MUCH better!

If you must use a Troughline with a decoder then you really need a Troughline Stereo model as a start. Then remove the unusably awful internal decoder and start thinking about external decoders from there. That or do all the updates to the 2 to make it same spec as a Stereo.

I've never noticed anything wrong with the bass in any of the units I've heard.
 
If you can find one second hand the Tim de Paravicini decoder I have on my TL stereo rewired by TdP as it had no multiplex out normally would use/plug in to the multiplex socket, works brilliantly despite what some of the curmudgeons on this site usually say...

Well, that is the problem, it is nowhere to be found.
Tim has left us, for some better place (RIP) just recently, btw.

I cannot find that decoder, (TdP Ear), Iwould prefer it, although some reports have said that the One Thing Audio is good as well, but now it is gone and vanished, just minutes from me purchasing it.
 
I've never noticed anything wrong with the bass in any of the units I've heard.

The problem was identical in both of mine Leak TL 2, both in mono and in stereo.
There have been even some threads elsewhere, dedicated to this very problem, reportedly.

I do own, and use one small (Cai's) mpx decoder, supposedly optimised for valve tuners.
It does it's job with stereo, but I have no idea whether the de-emphasis is done for the EU or the US standard.
 
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Seem to recall that Hi-Fi World offered a DIY supplement with details of a Tim de Paravicini decoder back in the early/mid 90s? My memory might be playing tricks, but pretty sure something was offered... I'll take a look in the loft later on the off-chance I happen to still have the supplement, might be of help.
 
Seem to recall that Hi-Fi World offered a DIY supplement with details of a Tim de Paravicini decoder back in the early/mid 90s? My memory might be playing tricks, but pretty sure something was offered... I'll take a look in the loft later on the off-chance I happen to still have the supplement, might be of help.

Well, thanks... yes... the lofts and their forgotten secrets...
 
There's loads of info around if one wishes to DIY a decoder. all the IC data sheets have suggested circuits but often without the "housekeeping" circuitry and PSU and you could just copy the circuitry in many tuner service manuals.
 
Seem to recall that Hi-Fi World offered a DIY supplement with details of a Tim de Paravicini decoder back in the early/mid 90s? My memory might be playing tricks, but pretty sure something was offered... I'll take a look in the loft later on the off-chance I happen to still have the supplement, might be of help.

Sounds about right my TdP built at EAR has Hi Fi World on the front.
 
I would look for one with pilot cancellation as the 19 kHz notch filters are unavailable now.
Alternatively buy a cheap old tuner and cannibalize it.
 
The best sounding Leak tuners are the mono Troughlines with the variable gain on the front panel, i.e. pre stereo. The audio from the mono tuner doesn't have to go through a stereo decoder so the fidelity is better, you just don't get stereo. Not sure that is much of an issue these days...

It has been claimed they they are the best sound quality-wise, even with the external decoder (TdP), in direct comparison.
There is a dedicated thread on it in another forum.
 
You're wasting your time - preaching to the deaf, I exit long before this stage. If somebody wants to argue black is white............................. just let them carry on. You are better off talking (posting) to a wall.

Yes I know! I nearly added some cheeky stuff about "but as you are only listening to those who haven't a ****ing clue you'll not be bothered!".
 
They are the worst! Not really suitable for stereo.

You're wasting your time - preaching to the deaf, I exit long before this stage. If somebody wants to argue black is white............................. just let them carry on. You are better off talking (posting) to a wall.

Yes I know! I nearly added some cheeky stuff about "but as you are only listening to those who haven't a ****ing clue you'll not be bothered!".

Like I said - go talk to a wall.

I just will not open the thread as I know that I'll get irresistably tempted.....

And all of that is, of course, applicable to others, who do not share the same impressions... the gents at the One Thing Audio, the London Sound, Graham Tricker, and some others... I keep an open mind to both possibilities, and then out of nowhere get characterised by the person with (or to) whom I have never spoke a single word (well, never written) anywhere neither here, nor elsewhere...

Well, nevertheless...

http://www.adventuresinhifiaudio.co...ne-tuner-compared-part-one-a-flock-of-tuners/

T
he article was nice to read, now, I am not implying anything by it, just citing it as an example.
 
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