NOT Small Advents!

[Pete B]

Since I'm sure someone is going to tell me that I've ruined the amazing Advent factory sound I'm going
to call these the NOT SA speaker.

I've replaced the tweeters with a current production 1" dome and designed a real mini monitor
style 2nd order (electrical) crossover with baffle step compensation.

A 3 position tweeter level switch is provided that on decrease provides a voicing very similar
to Celestion mini monitors, mid level is similar to a modern voicing such as KEF LS-50s, and high
is very bright as was done with many vintage speakers.

The tweeter had to be spaced forward to meet with the old grille frame and was centered on the baffle.

I'll be showing these at the Blue Mountain Audio Fest (GlennFest) in NY this weekend Sat Sept 15.

Teaser pictures:

 

[Oerets]

Truth be told most will experiment personalize their speakers at some time or another.
One of my favorite being a EV super tweeter in a AR2ax.

Bet this setup of yours works pretty well. I like that style tweeter also. Used one in a KLH with a 3 position switch resistor combo.

 

[Hajidub]

A parts-express AMT would be fun in that!

 

[ra.ra]

Hey Pete, those are pretty cool, and they look great with the centered black tweeter. I'd be curious to see a schematic and/or crossover pics. Also, would be interested to know more about the tweeter used..... and why did you select double terminals for wiring?

Maybe you can post more after the weekend event - - and give my regards to Glenn.

 

[RTally]

Sounds like a great mod. I have a pair of Advent 1 speakers and some tore up fried egg tweeters. I would like to know how you built your crossover and the specs on your tweeter. It sounds like a mod I could adapt to the newer version of the Small Advents.

 

[gdmoore28]

Looks good, Pete.

What was the crossover point on the original SA speakers?

GeeDeeEmm

 

[stickman]

Ok, enough of the teasing and mystery! What make and model number of tweeter are you using in this application and what cross-over components are being utilized (brand and rating please) with the tweeter? Inquiring minds want to know! (lol)

 

[blhagstrom]

As long as that spit wad woofer is in play, those are SA. Not OSA (old small advent) but now NSA (new small advent)

Nothing wrong with x-over and tweeter upgrades.

 

[Pete B]

Hey Pete, those are pretty cool, and they look great with the centered black tweeter. I'd be curious to see a schematic and/or crossover pics. Also, would be interested to know more about the tweeter used..... and why did you select double terminals for wiring?

Maybe you can post more after the weekend event - - and give my regards to Glenn.

I forgot to take a crossover pic before I installed the last one, will do it next time.

I used the bi-wire cup so that I could wire them direct to the drivers and outboard
the prototype crossover to make final voicing easier, then I move the crossover inside.
Certainly it could be done without the bi-wire posts.

 

[Pete B]

Looks good, Pete.

What was the crossover point on the original SA speakers?

GeeDeeEmm

The woofer is wired directly to the input terminal, in the original deisgn, so it is whatever
the Woofer's acoustical response is. The original is a cheap, minimal crossover, I didn't
measure or simulate it, just went ahead and did the redesign.
The redesign does provide a second order electrical networks on the woofer and tweeter.

 

[Pete B]

Sounds like a great mod. I have a pair of Advent 1 speakers and some tore up fried egg tweeters. I would like to know how you built your crossover and the specs on your tweeter. It sounds like a mod I could adapt to the newer version of the Small Advents.

I'm planning to do the NLA soon also which would apply directly to the Advent/1 as I'm sure you know.

 

[RTally]

I'm planning to do the NLA soon also which would apply directly to the Advent/1 as I'm sure you know.

I am looking forward to reading about your NLA mods. I appreciate your many contributions to documenting and making vintage speakers better.

I have both a pair of NLA and Advent/1 speakers. The NLA tweeters are trashed, so I was thinking of moving the Advent/1 tweeters to the NLA and experimenting with the Advent/1.

 

[leftfielder]

Hey I liked my long gone ADC 303ax but the tweeter was beat on one of them. I had in very rough shape a pair of KLH # 23 but the tweeters were good and I made the swap. They sounded great for Frankensteened speakers and when I flipped them it was w/ full discloser.

 

[KentTeffeteller]

I won't call you out on this one. I think you did some nice things to improve on an already fine speaker. Overall, sensible updates when implemented right (and I think you did so)

 

[Pete B]

These were a big hit at the Blue Mountain Audio Fest one friend who heard them now
has a WTB Small Advents in Barter Town and another asked me if the plans would be
published so he could mod his speakers. Many other WOWs from passers by.
The plans will not be public for some time, I have to figure out where to go with this.
I have to remind people that these are inefficient and 4 ohms, we ran them with an amp
that does 250W/ch into 4 ohms.

I did this work mainly because I've been asked to design the best mini monitor with deep
bass and I wanted to have these as an example of what can be done in a small acoustic
suspension design. I lean toward vented designs but if I can't beat these then I might
switch to sealed.

The best mini monitor that I've done so far is the Not So Mini Monitor which is in a 1 cuft
box, the SA is about .8 cu ft internal volume and I've not yet compared them side by side.

 

[RTally]

I hope you eventually publish the plans for your mod. I think most of know that acoustic suspension speakers, in particular the Advents, are inefficient and power hungry. And then there are the many that stack them wired in parallel. Not to mention those of us that have high powered amps just waiting for a load. What you have done sounds like a worthy mod to increase the SQ of a venerable speaker. I look forward to learning more.

 

[ultumax]

I couldn’t understand how to build crossovers, my rtr started getting static and they have obsolete speaker terminals.

How do These sound ?? Advent ?
Domes , or horn tweeter my favorite so far haven’t heard ribbon or super .
Speakers are so complex

 

[Supercool!]

These sound like a MUCH a large speaker that is extremely balanced with plush powerful bass and detailed non-fatiguing highs...wow is all I can say! Pete is a master...I'm the guy who put the WTB ad up and have a pair for pick-up that I am really hoping he'll give me a hand with...Pete...Pete..? Pete rocks!

 

[Pete B]

Thanks very much for the kind words!
I'll be happy to help you out Chris, just let me know.
How far are you from my area Trumbull, CT?

 

[Supercool!]

Hey Pete, Thank you so much. Im about 2 hours away but that would be fine with me..I wont have them until after Frankenfest and I won't be there unfortunately. This works out fine though because I have a bunch of medical tests ahead and they will probably be finished by then, hopefully giving me a little peace of mind. Ive been a lot more positive after seeing a doc a few days ago. I will definitely be in touch then...

Ive heard three special speakers at the Peekskill meet over the last two years that really made me stop in my tracks; your NOT SA's, Glenn's 910's and the "secret surprise" KLH's... By the way, also wondering if the speakers cables you were using were those nice Supra's you have for sale. All the best!