Aaron Speaker AST tweeter replacement guide ATS-1, AST-4, AST-5

[Angellus]

 

Hi Guys,

 

Thought i'd write this up as guide, or place to consolidate info on Aaron AST Speakers Tweeter replacement.

 

I got a pair of Aaron AST-1's returned to my care from a friend. I purchased them new 20 years, fortunately a few weeks ago when my friend could no longer use them and they had a blown tweeter so got to learn some new skills 

 

Pete put me onto this thread and info from clay.. its worth a read.. 

 

Anyways... to the details..  This is my Aaron AST-1 original Mk1, my ears, my gear, my room, speakers 55cm from back wall which makes a HUGE difference. Gear used is J river-> Xindac DAC5 tube output -> little topping class D amp - Amp kinda sucks, but its a good rig, sounds reasonably flat, and within reason for testing purposes as good as my much more expensive rigs. YMMV! Nuff said.. No I haven't measured as yet. 

 

Wiring diagrams here: http://www.aaronhifi.com/resources/circuit-diagrams.php

 

Tweeter replacement upgraded to : SB Acoustics SB26STC-C004 from WES for $30 if you can get a wholesale account, or $50 from Wagner retail. These are now no longer made, the new version is SB26STC-C005. The frequency response on the 005 looks very close if not better to the 004 if i remember correctly. I wasn't aware of this info at the time of purchase.

 

Caps: upgraded to Dayton Audio from WES or Wagner, the same value as the wire diagram on the AST-1. They sound great, good enough in this project IMHO.

 

I Also I glued in some 5mm Vinyl flooring I had left over from house reno's to the inside of the cab's as a cheap no-res substitute to try and deaden the cab. Advice I have received is that I also need to cover this with some felt or other similar material.

 

.............................................................................................. 

 

So all that done, the tweeters sound great.... but are to loud... After 100 hour burn in.... still to bright.. by my ears and some EQ'ing in J-River they need a drop of about -2 to 2.5db at around 2k to 2500hz... L-pad changes needed.. 

 

L PAD Changes...

See wiring diagram for ATS-1, and AST-1 Mark 2. I think the same L-pad is used for the tweeter in the AST-4 and AST-5.

 

From what I found out..  the first resistor marked #6 on the wiring diagram for the AST-1 as 1.2ohm need to be increased to roll for the tweeter but this will effect the both the high and low end of the tweeter response and alter the cross over as well as roll of some very high end. Resistor marked #7 at 33ohm will short to ground,  lowering this value is will cut ( short to ground ) the overall signal going to the tweeter and not effect the the high and low end of tweeter response. ***** my very limited understanding as noob.. please correct me*******

 

Working from the AST-1 wiring diagram

First change #6 resistor from 1.2ohm to 1.8ohm - tweeter lost some sparkle and magic it had, still to bright.

Changed to AST Mark 2 L-pad. #6 from 1.2 to 1.8ohm, #7 from 33 to 27ohm - sounds better, some loss of sparkle and top end to tweeter, sounds good near-field on a desk etc.

Changed #6 resistor to 1.80 and #7 to 22ohm - Bass is too woofy and wolly ( cab needs treatment with stuffing ) upper mid's are rolled off also, top end missing sparkle.

Put #6 resistor back to 1.2ohm and #7 at 22ohm.. Winner winner chicken dinner   Sparkely goodness is back, near field is bit to much of everything on some recordings, I may go back the Mark to 2 resistors if I use them as near fields, but as a room speaker its pretty damn good

 

Burn in time....

I wouldn't worry about it if your messing about and trying to dial in the speakers. I put 100 hours on the caps and tweeter before changing resistors, yeah the caps got better, but nothing you couldn't work with to dial in after an hour. Resistors - hmmm I put the speakers in my home theater as fronts this evening and think the sound stage got bigger after an hour,  you can hear a resistor value change straight away or after 2 minutes.  Don't worry about it, It's fine!!! burn in is just smoother and sound stage from my experience with this.

 

Other Info.

 

I talked to Clay at Gieseler Audio ( 20 years later and he's still giving me free tech support on speakers he sold me A++++++ for tech support )about lining speakers with absorbent material.. His advice was that he had tried lining AST-5's and he ended up taking out the stuffing. Use your ears I guess.. with 1.8 and 22ohm resistor cab stuffing would clearly be needed to absorb some low end.

 

My ideal values..

Id like to roll of a tinny bit of the very high end, im guessing 1.2 to 1.4ohm resistor or drop the 22 to 18ohm.. I'm out of resistors for today??? All advice appreciated. 

 

My questions. ..

 

Does anyone have measurements of the Aaron 6" driver and SB Acoustics SB26STC-C004 so I can do some models? is it worth it?

 

Links i found useful if your new to this like me...

 

 

 

 

 

Anyways .. that's it  Hope this post helps ppl with AST speakers

Edited July 2, 2020 by Angellus

[JakeHC]

Thanks so much for sharing this. I bought a pair of ATS-5's off facebook yesterday for $50, immaculate condition but didn't get to test until I got home. Unfortunately, one of the tweeters is blown. 

 

Did you replace both tweeters for your ATS-1s? 

 

Edit: Had a look around on the wagner online store, from what I can gather these would be the replacement for the ATS-5's, based off the power rating but I could be wrong. 

Edited July 5, 2020 by JakeHC

[Angellus]

Hi Jake,

 

Yep you will need to replaced both tweeters or the speakers wont match.  Those are the tweeters i used - or these are the new version of the tweeter.. I haven't done any research as to if they are better/ worse dif specs etc... https://www.wagneronline.com.au/sb-acoustics-1-dome-tweeter-st/sba-drivers/sb-acoustics/speaker-drivers/audio-speakers-pa/sb26st-c000-5-58691/976163/pd/

[joan1980]

iv just done a voice coil change on ats tweeter no problems  

[lolilun]

Hi, I've also got some ATS5s that have dead tweeters.

If I buy the replacement tweeters mentioned in this thread and simply swap them over will that work ok?

Sorry - no idea about capacitors etc

 

[elfreako]

I'm also interested in this. Though, after reading @bjc comment on 

I have a feeling my ATS-5 have faulty capacitors, too. I have just taken out the screws from the tweeter, but they seem to be fairly well stuck to the box. Is this a common thing? I'm somewhat cautious of getting something hard to pry underneath the tweeter plastic in case I do more damage than good. I'm also curious to know if the capacitor sits directly behind the tweeter, which would save me having to crack open the box. 

[bjc]

@elfreako They are just a tight fit in the mdf and from being mounted so long. Use a spring pick, a piece of bent wire or one of the screws you removed from the tweeter and lever them from the top screw holes and it'll come out easy enough.

The capacitors were all mounted to the single crossover board so just remove one of the woofers to see if it's glued on the wall of the cabinet or the binding posts. 

If mounted on the wall then you'll have to replace the capacitor with it inside the cab as removing the XO makes a mess, I'd also recommend changing the resistor at the same time for insurance as both are cheap and I wouldn't bother buying Dayton caps (cheap poly are fine) but it's up to you... 

[elfreako]

21 minutes ago, bjc said:

@elfreako They are just a tight fit in the mdf and from being mounted so long. Use a spring pick, a piece of bent wire or one of the screws you removed from the tweeter and lever them from the top screw holes and it'll come out easy enough.

The capacitors were all mounted to the single crossover board so just remove one of the woofers to see if it's glued on the wall of the cabinet or the binding posts. 

If mounted on the wall then you'll have to replace the capacitor with it inside the cab as removing the XO makes a mess, I'd also recommend changing the resistor at the same time for insurance as both are cheap and I wouldn't bother buying Dayton caps (cheap poly are fine) but it's up to you... 

 

@bjc thanks for your reply and tips. i was able to pop the tweeter out from the inside after removing one of the woofers. after inspection, it doesn't look like any capacitors are blown. which i guess is a good thing, as it's less hassle to replace the tweeter. both my tweeters went the way yours did, with the exterior crumbling off (they had been in my parents storage for 15 years). i have the Mark II of ATS5 and they are perfectly fine; no peeling and all in good working order. I suspect i now just have to replace the tweeters with something alike.

[bjc]

@elfreako You won't be able to tell if the capacitor is a dud or not without testing it. It's not like in a powered circuit where they swell or explode... I can guarantee that it's the caps as I learnt that same lesson before finding out the information...you'll install the new tweeter and it'll be dead as soon as a signal is sent to it. 

This is the case with every Aaron speaker I've bought new (3 out of 9 speakers after about 20years) and bought second hand.

Remove and test the capacitor otherwise it will be an expensive lesson (mine was $160 odd directly from Aaron for the diaphragm only)! 

[elfreako]

@bjc oh, that's interesting to know. just for the sake of completeness and understanding, here's a photo from the inside of the wiring. it's the two wires i've tagged which are from the tweeter, which doesn't look to be connected to the same type of capacitors that people have shown in previous photos....

 

[bjc]

@elfreako Apologies for the late reply... Please see the attached PDF (ATS-5Xover) diagram. The layout on the physical board can be a little confusing but It'll be the far right capacitor in your picture that's for the tweeter along with those two resistors being in series (1.2ohm) and parallel (33ohm) and the inductor below the two resistors also in parallel (0.16mh). 

Hope this helps 

 

Cheers, 

Brett 

ATS-5Xover.pdf

[Gieseler Audio]

Great advice @bjc & you are spot on.

I was a Aaron dealer for many years and replaced lots of tweeter capacitors 

which had failed & caused the tweeter to stop operating.

Tweeters did occasionally fail but definitely worth replacing the capacitor as a first option.

 

@elfreako

It's the light blue capacitor on the right  -  value 3.3uf.

The resistors look fine - they would normally look discoloured or burn when faulty.

Cheers Clay

[elfreako]

@bjc & @Gieseler Audio thanks for your input, it's much appreciated. i'll post an update how i get on (whenever that might be).

[Gieseler Audio]

Wow those Aaron's are a long way from home

Ballina Australia to London UK

[elfreako]

Ah, actually it's a reunion. I left 15 years ago and they've been with my parents in storage ever since. I've just moved back and found them in this condition. I missed them, and want them working again

[Gieseler Audio]

The ATS series were really nice, my favourite were the ATS5's.

[elfreako]

@bjc & @Gieseler Audio  I just bought a single tweeter from JayCar for $20 to do a test, and replacing it without doing any resisters/capacitors works for both speakers. Seems they just died. For me that's easier to fix than the wiring, which is good for me, but not for originality of sound.

 

 

@Gieseler Audio, I have 2x ATS-5 MKII, 2x ATS5-MK1 (the faulty tweeters), 1x CC-240 and 1x SW-400 

[Gieseler Audio]

Wow nice all Aaron setup.

Yes I also replaced a number of tweeters so not unusual.

With the tweeters it was usually the lead out wires that broke as they were just

the normal coil wire.

On a number of occasions, I did actually manage to repair the tweeters  by very carefully

unwinding a turn from the voice coil and then re-terminating.

It is fairly precision work but definitely possible as the tweeter faceplate/dome/voice coil all comes off fairly easily just by removing the screws.

A fine pair of tweezers  and some precision soldering required.

Edited December 16, 2023 by Gieseler Audio

[Angellus]

WOW it feels like 10 years ago I started this thread. Only 4 1/2 

 

Seems like now days with modern DAC's everythings getting a bit brighter and more detailed. Also I picked up a pair of AT3 Mk3's which are a lot brighter, and a bit laid back in the mids (paired with a old Cambride Audio amp they work great) compared to ATS4's I modded a while back, I do like the top end detail and stageing in the ATS3's. They make the ATS4's sound a bit rolled of in the top end.

 

Anyways.. with the SB Acoustics SB26STC-C004 tweeter in the ATS4 I changed the Lpad that I had modded to 22Ohm back to stock 33ohm. Much better..

 

I'll update if i do any more changes.

[harry_mr]

On 16/12/2023 at 3:42 PM, Gieseler Audio said:

Wow nice all Aaron setup.

Yes I also replaced a number of tweeters so not unusual.

With the tweeters it was usually the lead out wires that broke as they were just

the normal coil wire.

On a number of occasions, I did actually manage to repair the tweeters  by very carefully

unwinding a turn from the voice coil and then re-terminating.

It is fairly precision work but definitely possible as the tweeter faceplate/dome/voice coil all comes off fairly easily just by removing the screws.

A fine pair of tweezers  and some precision soldering required.

I still have my set of ATS5 you sold me Clay from the mermaid store a good old brick and mortar store. I'm going to start with the capacitors and like others said see what the tweeters do and then go to WES. What was the go with the stuffing inside leave it or line the boxes with no -Rez or similar? Thanks

[Gieseler Audio]

Wow a blast from the past!

Yes I really did like the ATS 5's 

Probably my most popular selling Aaron Loudspeaker.

 

From memory they have no internal damping at all.

It used a  special deflection brace design to break up the internal standing waves.

A long time ago but I do remember experimenting by lining the internal sides with inner bond wadding.

Unfortunately it had a negative effect.

I would just leave as is & find a nice tweeter from WES that fits the rebate.

I think the face plate on the teardrop tweeter Aaron used was a bit below the normal size

so probably not many to chose from.

Good Luck

[harry_mr]

1 hour ago, Gieseler Audio said:

Wow a blast from the past!

Yes I really did like the ATS 5's 

Probably my most popular selling Aaron Loudspeaker.

 

From memory they have no internal damping at all.

It used a  special deflection brace design to break up the internal standing waves.

A long time ago but I do remember experimenting by lining the internal sides with inner bond wadding.

Unfortunately it had a negative effect.

I would just leave as is & find a nice tweeter from WES that fits the rebate.

I think the face plate on the teardrop tweeter Aaron used was a bit below the normal size

so probably not many to chose from.

Good Luck

Ok thanks I will work with that, cheers Clay 

[Gieseler Audio]

Maybe this one

SB26STC-C000-4

https://www.theloudspeakerkit.com/sb26stc-c000-4-sb-acoustics-1-dome-tweeter-stc

100 mm dia faceplate