Information about Amw A340 speakers.

[AMW owner.]

Specifications,power handling,cross overs.

[carnicero]

Here you go.

[GRP]

 What is near 18 months in the scheme of things to get the information you wanted!

 

Back in the day some 40 years ago, the AMWs at Encel were the best thing I could hear under $1K until I was blown away by the "ugly" concrete ball Audiospheres which I bought on the spot.

 

 

[carnicero]

I am currently running a pair of 440's and am picking up a pair of the 340's today! Paired with my Marantz 2275, a system exactly my age, and sounds beautiful.

[Misternavi]

2 hours ago, carnicero said:

I am currently running a pair of 440's and am picking up a pair of the 340's today! Paired with my Marantz 2275, a system exactly my age, and sounds beautiful.

I picked up the A230 and they do sound good. It does have that 'VINTAGE' sound quality.

 

My concern is the inductors in the A230 the wires look like 33ga. wire. it's as thin as hair. Mine had snapped off when I had it transported to Melbourne .

[surprisetech]

Here are some details and a review of the Model 4100 from the same era.

It appears they were highly regarded.

[carnicero]

Awesome! I have always been on the lookout for these.

 

[carnicero]

Does anyone have information in regards to the height and angle of the stands for the first series ie A440 and A340?

[surprisetech]

On 12/09/2020 at 12:28 AM, carnicero said:

Does anyone have information in regards to the height and angle of the stands for the first series ie A440 and A340?

Can't offer specifics, but general rule-of-thumb for stand height is to bring tweeters up to ear level in your normal listening position.

Stands with adjustable spikes/feet would allow you to experiment with the angle.

[unclemack]

Great info here. Mine are the 440s. Can someone post a pic of theirs with the grille off? I want to check to see if my drivers are original. Cheers. M

[carnicero]

I will take some photos soon and post them for you

[AMW owner.]

Just picked up a pair of Kef kit 3 speakers,to join my AMW A340 , surprisingly similar they sound.

[Antipodean Brad]

Very nice - congratulations.  Don't forget the photo's.

[AMW owner.]

Replacing the Yamaha NS-344 speakers. The Kef kit 3 were built in 1978 by the previous owner in the UK, was going to dump them if no interest on gumtree.have cleaned them up and new capacitors on crossovers.

[Allan]

I just picked up a nice pair of the 4100's with the Bextrene mid as the above catalogue.  I'm yet to inspect the xover, one box is missing its driver tamper wax but the other is intact so I'm inclind to think the caps will be original.

 

Using a Krell KSA, compared to Proac Studio 125 the presentation is more forward, bass is tighter, mids are just as nice, the highs resolve well but for me they're a tad to much. I'm using silver XLR to the amp but think I need to try copper as I doubt these speakers were voiced with anything silver. The stage shows great potential, its 3D.. but more positioning is calling. Has me wondering on component age and how a Pommy studlo today would stack up if these rec'd a little TLC. 

 

Has anyone replaced their 4100 caps and if so, how did the speakers react? Any info or comments on the xover would be great

 

 

 

 

 

 

Edited July 27, 2024 by Allan

[Allan]

well I removed a bass driver today for a peek, looks a very simple xover, 2nd order. There's no resistors, this may explain why voicing is a tad high for my likes as no way all driver's have equal efficiency. Possibly some of the caps are out of spec too which won't be helping xover points.

 

 

Coil orientation, an easy fix

 

The seperate mid tube enclosure has an interesting OD spiral I guess for reinforcement, when I knuckle wrap its OD its rock solid. The box is very well braced, the mid enclosure is adhered to the baffle and rear panel so also acting as bracing. On sidewalls there's the bitumen dampening, black texture in center of below image. There's real good BBC traits in the box.

 

 

AWM 4100 impedance & phase, measured using DAT3. Impedance drops to just under 4Ω around 4400Hz, I dont like this, needs investigating. The rest of the curve is quite friendly.

Fb 40Hz

 

 

Will do frequency response next.....

 

 

 

 

Edited July 27, 2024 by Allan

[Allan]

did a rough and ready gated response on mid axis, results reflect what I was hearing. Around 18dB difference between 2 & 4 kHz.  

All drivers need to be independently measured (in box) so I can simulate the xover as is, then tickle things to tidy up the 4.4 kHz phase dip and level off the frequency response. The driver efficiency matching across the board isn't to bad.

 

Edited July 28, 2024 by Allan

[Allan]

Been using these 4100 speakers over the last week after changing out the pure silver interconnects too silver coated copper. I think some current through the speaker caps has done them good... they've really woken up and are sounding very, very nice. Listening now to some Jimmy Vaughan, Jeremy Spencer, Alvin Lee & Chicken Shack on them.. they tick all the right boxes 

 

They respond well to room placement and are a bit fussy in this regard, bit further back and a tad wider than the Proac 125s which are rear ported speaker

 

The decision is made, these 4100's will get a recap and so while in bits, I plan to model the xover and each driver's independent in box response (without xover) so I can model everything in Xsim. Will upload xover schematic & some response plots once I'm all done.

 

Edited August 9, 2024 by Allan

[Allan]

can anyone confirm please what type of caps the yellow & green are in the xover pic above?

 

Thanks

[surprisetech]

4 hours ago, Allan said:

can anyone confirm please what type of caps the yellow & green are in the xover pic above?

 

Thanks

 

Not sure exactly what type the Shizuki caps are, but they are a film type, not electrolytic, or PIO.

In the past I've seen the brand used as mains supply filters or motor-start capacitors.  Given their type and voltage rating, yours are probably still in spec.  Not sure how they rate as crossover caps, but they would have been a cost-effective way of getting the required value at a good price.

 

The green one is a polyester cap, commonly known as 'greencaps' funnily enough!

Once again, unlikely to have deteriorated much.  I remember seeing a bunch of these paralleled up to achieve the required capacitance for a woofer-midrange crossover circuit in one of the kit speakers from the electronics magazines in the 80s.  The approach yielded very good results at a much cheaper cost than a single large-value poly cap at the time.

 

Needless to say, if the black ones (electrolytics) are original, they are the first ones to replace.

[Allan]

Replaced the electrolytics with some Jantzen Cross-Caps, I'm stoked with the direction sonics have gone, more on that later but for now how's this..

 

 

Edited August 14, 2024 by Allan

[Allan]

well turns out one of the midrange Audax Bextrene drivers has a voice coil issue, I can hear it scrape when softly pushing on the cone.

 

Anyone know where I can buy replacements or suggest a suitable substitute (I'll change both L&R mids)

 

Pity because these speakers were sounding really good over the weekend but I did hear on the occasion a little fizzing type sound coming from the suss mid driver.

[VanArn]

There are some speaker parts left over from the time Bill Webb distributed the Audax range. A repair of the mid-range unit may only require new flexible voice coil tinsel leads as Audax at one time used a white pvc sleeved type that failed after a few years. The next step to take is to identify the model number; it should be a HD 13 B 25 J or HD 13 B 25 H.

[Allan]

Thanks @VanArn will pull out the suss driver and see what details i can find. 

 

thanks

[Allan]

Can someone help with the value of this poly greencap please?