Advent Heritage Resto-mod - has anyone tried this?

[seventy1]

I think I’ve read everything that Google can point me to, but I’m still looking for advice on uprading Advent Heritage speakers to improve their lower mid clarity/detail, some say, wooly sound. I picked up a near perfect pair last weekend and have really been enjoying them, but would like to take them to the next level. I’ve seen posts talking about recaps, updating inductors, bracing, added damping material, but no real feedback on the end result. Maybe what I’m hearing is just inherent in the 2.5-way design and it is what it is. I’m not really interested in changing drivers or converting to a 2-way design.

I can recap, sure, but since the caps only feed the tweeter circuit, I’m doubtful that will do much in the lower range. Does anyone have experience with this on Heritages? The surrounds are, surprisingly, the originals and solid, but they feel very compliant. This is usually a good thing, but could the aged surrounds make the woofers are under-damped? I bought replacements thinking that could tighten up the bass. The roll on the replacement surrounds is ~5 mm smaller, so I don't want to replace good originals for no or negative gain, thoughts?

Has anyone changed out the iron core inductors, braced, added fill, or other and what did this do to the sound? If these weren’t already nice sounding, great looking speakers, I wouldn’t waste my time. But I do feel they’re worth the effort. Thanks for any help!

Pictures below, the crossover diagram and photo were borrowed from other posts.

 

[seventy1]

Just bumping this to see if anyone has modified the Heritages.

 

[Bicyclist]

I have a set of laureates. The 6.5 version. My surrounds were shot. When working properly they sound a little hot on top to me and somewhat light in the vocal midrange. I kind of gave up on them when i got polk m7s

 

[seventy1]

Thanks. The Heritage's are really nice sounding. In fact, if I wasn't switching back and forth between them and my AR91s, I probably wouldn't have noticed the lack of detail. I'm decided, I think, that I'll just refoam, even though they don't need it, recap, then go from there.

 

[Bicyclist]

I would imagine those have prodigious bass performance. They sure look good .

 

[Thom 2230]

Hey Seventy1 I am curious if your refoaming experiment had any effect. And if you've done any other tweaks to improve the originals. I have a pair of Heritage speakers also, sadly mine were not in as good shape when I got them. I had to refoam and replace tweeters. I have wondered about recapping them simply because of there age.

 

[Pete B]

I'd refoam them with filled fillet surrounds since they probably help
to reduce cone breakup a bit. I would not go with more narrow surrounds.

I do not know of any mods for these and actually I see very little about the
"other" Advent speakers.

It is good that there are inductors in series with the woofers and they are
fairly large to provide some baffle step. But just an inductor does not really
provide much electrical roll-off in the stop band rather they rely on the
acoustical roll-off of the woofer cone - not always a good thing.
Do you have any measurement gear?
You usually can't just add a capacitor across the woofer due to the high voice
coil inductance of these older drivers and R is needed in series to avoid peaking
in the response.

Do you have the part number on the tweeter or at least know the DC resistance?
That is the standard Advent 3rd order tweeter crossover for the poly dome tweeters.

 

[wallacefl]

If the crossover is really 3.5k...it is just too high. I wonder if converting it to a Fast design or an Econowave would be better options?

 

[Pete B]

Link to "Fast design" ?

 

[baco99]

I have worked on Several pair of these. I also love the look, but I agree the sound is a bit muddy in the lower midrange. I think you can make some improvements on this speaker.

1) If you want to keep the same crossover point, I would suggest a recap, and also replacing those really cheap, iron core inductors with Jantzen or Dayton air core inductors.

2) I would also add fiberglass stuffing to the cabinet. The sets I have worked on have a very little amount of fiberglass or fiberfill insulation inside, its just not enough. Doubling the amount really helps the bass go deeper and more evenly through the frequency range.

3) Lastly, your idea of adding some internal bracing is spot on. Although the front and top of the cabinets are solid pecan wood, the sides, back, and bottom are cheap 3/4" particleboard. I would spray the inside of the cabinet with a non-resonant spray, something like a bedliner paint, and then put 3-4 braces across the cabinet to really deaden the enclosure.

These are all low cost options that should vastly improve the sound.

I don't have any before or after measurements, but my seat of the pants reaction is, do these things.

 

[seventy1]

Thanks very much for the input, guys. I’ll try to optimize the original design concept before turning to more radical changes. I like the idea of the bedliner application. I was also thinking of gluing open cell foam to the interior walls. I have some Solen caps and new resistors on hand, sounds like I should look for some air core inductors too. Hmm, I may have to fabricate a remote XO board to fit all of these larger bits...

 

[seventy1]

Pete, I don’t have any measurement or modeling tools, but I can measure driver resistance. I’ll report back once I’ve done this. Thanks.

 

[Bicyclist]

Thanks very much for the input, guys. I’ll try to optimize the original design concept before turning to more radical changes. I like the idea of the bedliner application. I was also thinking of gluing open cell foam to the interior walls. I have some Solen caps and new resistors on hand, sounds like I should look for some air core inductors too. Hmm, I may have to fabricate a remote XO board to fit all of these larger bits...

I will say the laureates could have used cabinet stiffening as well. They seemed to be a great plan that just needed a little help.

 

[Thom 2230]

I have to say here, guys, I am new to this world. I bought these speakers which a wiser man would have walked away from. When I found them the foam was shot on the woofers, the tweeters were Radio Shack replacements, and if this weren't enough the cases had moisture damage. The woodworking end of this is the only thing I really qualified to do - but I reformed the speakers with Simply Speakers foam and replaced the tweeters with new original Advent tweeters. (I'll send along finished photos later) So basically I brought everything back to zero. Now I want to continue and try to get as much out of the speakers as possible. I am un clear about the internal bracing, what would this look like? And do those members get added before the bedliner?

 

[Bicyclist]

I have to say here, guys, I am new to this world. I bought these speakers which a wiser man would have walked away from. When I found them the foam was shot on the woofers, the tweeters were Radio Shack replacements, and if this weren't enough the cases had moisture damage. The woodworking end of this is the only thing I really qualified to do - but I reformed the speakers with Simply Speakers foam and replaced the tweeters with new original Advent tweeters. (I'll send along finished photos later) So basically I brought everything back to zero. Now I want to continue and try to get as much out of the speakers as possible. I am un clear about the internal bracing, what would this look like? And do those members get added before the bedliner?

I would put 1 by 1 sticks across the cabinet. 1 stick at the center from side to side would go a long way toward stiffening it up.

 

[Thom 2230]

Bicyclist, after reading your suggestion for a stiffener across the speaker enclosure I held the sides of the box while playing music. There is a lot of vibration coming through. Is the goal to stop as much of this as possible? Would two or three braces be over kill?
On another note I see you are a bagger, ever done Ragbrai?

 

[Bicyclist]

Bicyclist, after reading your suggestion for a stiffener across the speaker enclosure I held the sides of the box while playing music. There is a lot of vibration coming through. Is the goal to stop as much of this as possible? Would two or three braces be over kill?
On another note I see you are a bagger, ever done Ragbrai?

The more u do the stiffer it gets but it also takes up a small amount of cabinet volume which will raise your resonant frequency ever so slightly. So be judicious. The idea is to have it not noticably vibrate. You wont get there without major surgury but you can improve it.
I dont do organized rides generally. Just like to take off from my house in peoria illinois and see where i end up. Done chicago and back 2 times and rode to devils lake wisconsin last year. For a 62 yo its a fun way to get out. I try to camp most nights.

 

[seventy1]

A quick update - the speaker passive resistance through the XO is 2.7 ohms, tweeter 4.0 ohms, and woofers 4.9 ohms. The components themselves are not overly impressive, light gauge stamped baskets, medium sized magnets, plain unweighted cones. The tweeters also look fairly simple and others have commented on the economy inductors. It looks like most of the budget went into aesthetics, the cabinets' 3/4" solid wood front and top panels. The other panels are 5/8" low-density fibreboard (LDF). The stuffing is a single piece of fiberglass, randomly jammed in the box. I was checking out the woofer surrounds to see how soft they were and they tore with a light tug, so these will definitely get replaced. I think lots of bracing and the bedliner coating are also needed; possibly bedliner or other damping material on the speaker baskets?

 

[Thom 2230]

I have worked on Several pair of these. I also love the look, but I agree the sound is a bit muddy in the lower midrange. I think you can make some improvements on this speaker.

1) If you want to keep the same crossover point, I would suggest a recap, and also replacing those really cheap, iron core inductors with Jantzen or Dayton air core inductors.

2) I would also add fiberglass stuffing to the cabinet. The sets I have worked on have a very little amount of fiberglass or fiberfill insulation inside, its just not enough. Doubling the amount really helps the bass go deeper and more evenly through the frequency range.

3) Lastly, your idea of adding some internal bracing is spot on. Although the front and top of the cabinets are solid pecan wood, the sides, back, and bottom are cheap 3/4" particleboard. I would spray the inside of the cabinet with a non-resonant spray, something like a bedliner paint, and then put 3-4 braces across the cabinet to really deaden the enclosure.

These are all low cost options that should vastly improve the sound.

I don't have any before or after measurements, but my seat of the pants reaction is, do these things.

 

[Thom 2230]

Baco99 can you suggest a source for the Jantzen or Dayton capacitors and their values.