Luxman L309

[ZeroMostel]

I feel like I’m so late to the party. I’ve always loved my music but never considered myself an audiophile. Certainly my equipment over the years has either been just found roadside (I love hard rubbish - Aussie speak for biannual council collection of unwanted items that can’t go in the trash or recycling) or gifted to me. NAD 7125, Rotel RX-830, Bose 501-Sii, a vintage Sansui amp that I now regret gifting on. My sole legacy purchase was a pair of TDL Studio 0.5 speakers which are still much loved. Now the combination of prolonged Covid enforced lockdowns in Melbourne and having older independent children has provided me with the luxury of time to venture into an area of interest that I’ve never explored. And at this point I would like to thank you all for offering a forum that is so wonderfully informative and accessible. And that has enabled me as a novice to venture into the audio abyss. With the TDL Studio 0.5 speakers as a starting point, I’ve added a Rega Planar 2 (because one is never too middle aged to be a hipster) and I’ve been driving this with the NAD 7125 (because I read it has great phono support although a little underpowered). So I tried to purchase at an auction a NAD 1155 pre amp together with NAD 2200 power amp. However came away with the power amp only! So I’ve now purchased a Luxman L309 which I’m expecting delivery of this week (very excited!).

Which brings me to my question - should I choose to bi-wire my speakers using the Main AND Remote speaker terminals, are these terminals wired in Series or in Parallel on the the Luxman L309 amp?

I am very much a novice in this space and have read ad nauseum the bi-wiring debate. I also understand that most vintage amps wire the main and remote speakers in parallel. Which I understand would allow me to use both the main and remote speaker terminals to bi-wire. If these terminals are wired in series I understand it’s a no-no. The fact is I’m keen to experiment and see whether I can hear any discernible difference in sound quality given the TDL speakers are transmission line speakers. However, I don’t want to risk damage to the amp or speakers by mis-wiring. So any guidance would be most appreciated. Really!

Apologies for the ramble but I read the intro page and the forum rules and agree that sharing a bit of me and my context makes for a more grounded forum. Thanks again.

 

[mbz]

hifiengine is a great resource for free service and owners manuals, need to register to filter out robots, it's safe, no spam.
The L-309 is a nice amp, your speakers are 6ohms DC resistance, will check the 309's ability to drive (hopefully in the sm).
Possibly the L-309 will need some work (as with all vintage), give it a listen then go from there...

 

[ZeroMostel]

Thanks mbz for the speedy reply! Will have a look at hifiengine. Question re your post - what does ‘ability to drive in the sm’ mean?

 

[mbz]

Service manual did not include spec's/4ohm capability, you are "probably" ok but I wouldn't push the amp too hard, spkrs are SPL 85dB so the amp is working hard enough(?)

Service manual shows 2SC1345 transistors used along with some tantalum caps, both are
potential noise sources, again, give it a listen and go from there. Speakers are wired in parallel.

 

[mbz]

what does ‘ability to drive in the sm’ mean?

Whether the amp can handle 4ohm loads, ie, 2 sets of nominal 8 ohms connected in parallel. Specs often give
power rating into 8ohms and then into 4ohms. Unit does not appear to have any warning on the rear however
it's an early amp...

 

[ZeroMostel]

So in simple terms:
- the amp’s main and remote speaker terminals are wired in parallel allowing bi-wiring if desired
- however given the speakers are 6ohms, this may place too much stress on the amp if bi-wiring
- I can give it a go to assess sound differential from standard wiring but avoid high volumes
Correct?

 

[mbz]

Yeah, give it a go but not at party volumes. I wouldn't bother, I don't understand the arguement/math,,, for bi-wiring though
that's another thread... if you feel you must then do it with some moderation.

 

[ZeroMostel]

Really appreciate your help. Thanks so much.

 

[Akustic]

Presuming that your speakers have two sets of terminals .. Bi-wire from the same set of amplifier terminals ...

There is no need for two separate connections to the amp ..
What you are doing is providing two separate circuits, one for each section of the crossover ..
One of the potential benefits of bi-wring comes from having strong bass signals in a separate circuit from a weaker treble signals ..

 

[Akustic]

So in simple terms:
- the amp’s main and remote speaker terminals are wired in parallel allowing bi-wiring if desired
- however given the speakers are 6ohms, this may place too much stress on the amp if bi-wiring
- I can give it a go to assess sound differential from standard wiring but avoid high volumes
Correct?

You can only biwire if the speaker has two sets of terminals on the back ....
Running two wires to the speaker from the amplifier is not biwiring ..

 

[ZeroMostel]

Presuming that your speakers have two sets of terminals .. Bi-wire from the same set of amplifier terminals ...

There is no need for two separate connections to the amp ..
What you are doing is providing two separate circuits, one for each section of the crossover ..
One of the potential benefits of bi-wring comes from having strong bass signals in a separate circuit from a weaker treble signals ..

The speakers do have separate terminals at the back which is why I was keen to test bi-wiring.

 

[Akustic]

The speakers do have separate terminals at the back which is why I was keen to test bi-wiring.

You're set then ..

Use the same kind of wire in the same length and keep the two wires about an inch or so apart .. (this should minimize EMF field interactions in the circuits)
You may or may not hear a difference .. depends on the components ..
The amp won't care if both sets of wires are connected to one set of terminals .. you would defeat the bi-wiring if you connected to separate terminals at the amp ..
Bi-wiring does not change the power provided to the speakers .. you can expect to use the same volumes that you normally would ..

 

[ZeroMostel]

Will do! The amp has spring loaded speaker terminals so not ideal for connecting two wires to a single terminal. May try some pin connectors if it doesn’t matter if the source connection comes from the same terminal. Many thanks.

 

[Akustic]

Will do! The amp has spring loaded speaker terminals so not ideal for connecting two wires to a single terminal. May try some pin connectors if it doesn’t matter if the source connection comes from the same terminal. Many thanks.

Just use a wire stripper and thin the two wires until they fit ... they're all in contact down the wire.
Wasn't sure what time it was there ..

And do remove the strap or wire which connects the two terminals at the speaker together ..