[L0rdGwyn]

BTW. If you have the cash, you can also order the audio note tweeters and woofers and make your own AN-J speaker. It's probably not the right time to be going down that rabbit hole, but if you ever have an issue with your drivers later on down the road, keep that in mind.

I put together the crossover in LTSpice to get a rough idea of the crossover point (2kHz), but the inductor values are not marked. A quick Google search and I found a schematic of the AN-J crossover, yup they are still using the exact same one. Very slightly different component values, funny the longevity of this design.

I actually emailed Peter Q asking about using his drivers in a Snell cabinet last week out of curiosity, but he recommended sticking with the originals and keeping the original crossover since they are not an exact 1:1 replacement. Well keeping the original crossover parts is out the window now considering this tweeter condundrum, the only differences between the two crossover components are in the RC of the tweeter filter, the woofer components are identical. I will likely choose an average and make both crossovers the same since I will be using new tweeters. No difference between the two crossovers is going to be as audible as using two different models of tweeter. I'll likely be using Clarity Cap ESA caps in the overhaul, pretty cheap, relatively small for films, and have all the values I will need.

 

[L0rdGwyn]

Just got off the phone with Atomic Hifi, placed an order with them. I doubt what I will be receiving are the original J/II tweeters, likely an OEM equivalent or the J/III tweeter. The original J and the J/II used a specific doping material on the diaphragm which dries and cracks over time, it is pretty uncommon for the doping to be in good condition like it is on my mismatched pair of tweeters, although one is starting to crack in one spot, usually they are falling apart. Regardless of which model, they will be matched pair. These speakers are moving away from an "original" label and moving more toward "modded" territory anyway considering what I am doing with the crossovers, but I think they are going to sound fantastic.

Speaking of crossovers, I prepped the boards for their new parts. The original caulk was removed with a plastic razor, I will apply new caulk when putting them back together to seal the cabinets. I reheated some of the old glue with a heat gun to afix one of the inductors that had fallen off, which worked great. Possible I will have to completely change the layout to accomodate the Clarity Caps, we will see.



Here is one of the cabinets with everything taken out and caulk removed, I also polished up the veneer. I absolutely love walnut and the grain on these speakers is just my taste, another reason I am going to such great lengths to restore them, these don't come up often in walnut.



So the stage is set, parts are ordered, should have these back together and rocking by the first week of July, very exciting!

With that taken care of, I am back at a fork in the road. I am in a holding pattern with the 841/801A amp, just about everything is done except for the signal wiring, also waiting for some parts, I had to make some adjustments on the Coleman regs to accomodate filament bias on the 841. I might do some minor work on it in the mean time, but much of the major work is complete.

Then there is project three...the 6A5 amp revamp. I guess this is where I will focus some time, but I am still hung up on whether to switch to R120 as the outputs, the sound is quite different than the 6A5 and I haven't yet decided if it is more to my liking or not. So I think I will have a cup of coffee, enjoy some music on the Omegas and do some more comparison of R120 vs. 6A5G.

 

[Tjj226 Angel]

Just got off the phone with Atomic Hifi, placed an order with them. I doubt what I will be receiving are the original J/II tweeters, likely an OEM equivalent or the J/III tweeter. The original J and the J/II used a specific doping material on the diaphragm which dries and cracks over time, it is pretty uncommon for the doping to be in good condition like it is on my mismatched pair of tweeters, although one is starting to crack in one spot, usually they are falling apart. Regardless of which model, they will be matched pair. These speakers are moving away from an "original" label and moving more toward "modded" territory anyway considering what I am doing with the crossovers, but I think they are going to sound fantastic.

Speaking of crossovers, I prepped the boards for their new parts. The original caulk was removed with a plastic razor, I will apply new caulk when putting them back together to seal the cabinets. I reheated some of the old glue with a heat gun to afix one of the inductors that had fallen off, which worked great. Possible I will have to completely change the layout to accomodate the Clarity Caps, we will see.



Here is one of the cabinets with everything taken out and caulk removed, I also polished up the veneer. I absolutely love walnut and the grain on these speakers is just my taste, another reason I am going to such great lengths to restore them, these don't come up often in walnut.



So the stage is set, parts are ordered, should have these back together and rocking by the first week of July, very exciting!

With that taken care of, I am back at a fork in the road. I am in a holding pattern with the 841/801A amp, just about everything is done except for the signal wiring, also waiting for some parts, I had to make some adjustments on the Coleman regs to accomodate filament bias on the 841. I might do some minor work on it in the mean time, but much of the major work is complete.

Then there is project three...the 6A5 amp revamp. I guess this is where I will focus some time, but I am still hung up on whether to switch to R120 as the outputs, the sound is quite different than the 6A5 and I haven't yet decided if it is more to my liking or not. So I think I will have a cup of coffee, enjoy some music on the Omegas and do some more comparison of R120 vs. 6A5G.

Does all this effort mean that you feel like there is a potential for the snells to be better than the omegas?

I ask because my next step in DIY speaker design was to mimic the omega design of having two similar drivers in the same box. If the snells might end up being better, then Im not even going to go down that path.

 

[L0rdGwyn]

Does all this effort mean that you feel like there is a potential for the snells to be better than the omegas?

I ask because my next step in DIY speaker design was to mimic the omega design of having two similar drivers in the same box. If the snells might end up being better, then Im not even going to go down that path.

It's hard to say, I think the Omegas are still burning in and they are very different sounding speakers, different strengths. The Omegas are mid-forward, very textured and detailed midrange, clean airy treble, that seems to be their area of strength. The Snells (the way I received them) are relatively more neutralish in that area. What has been the big shocker is the bass of the Snells is more impactful and full than the Omegas so far! I can feel the bass of the Snells more, they seem to move more air with sharper transients on the low end. Not sure what your experience has been with them, but to my ears they reach lower than their ~50Hz rating, just may take better advantage of room reinforcement. It has proven to be true that the Omegas do need burn in as the sound has changed quite a bit, I am probably at 20-25 hours in and the midrange and treble is fantastic, but I expected the dual 8-inch driver setup to knock me over with its bass (as much as a stand mount can), which hasn't really happened. They have bass, but it falls off rather rapidly. Is this a weakness of full-range designs? I'm not sure. Yet another confounding variable is that my 6A5G OPT are not wired ideally for the Omegas, they are wired for an 8ohm load whereas nominal of the Super 8 HO is 4-6ohm, which is very likely affecting low end performance.

So, that is a long way of saying, I don't know yet.

 

[Tjj226 Angel]

It's hard to say, I think the Omegas are still burning in and they are very different sounding speakers, different strengths. The Omegas are mid-forward, very textured and detailed midrange, clean airy treble, that seems to be their area of strength. The Snells (the way I received them) are relatively more neutralish in that area. What has been the big shocker is the bass of the Snells is more impactful and full than the Omegas so far! I can feel the bass of the Snells more, they seem to move more air with sharper transients on the low end. Not sure what your experience has been with them, but to my ears they reach lower than their ~50Hz rating, just may take better advantage of room reinforcement. It has proven to be true that the Omegas do need burn in as the sound has changed quite a bit, I am probably at 20-25 hours in and the midrange and treble is fantastic, but I expected the dual 8-inch driver setup to knock me over with its bass (as much as a stand mount can), which hasn't really happened. They have bass, but it falls off rather rapidly. Is this a weakness of full-range designs? I'm not sure. Yet another confounding variable is that my 6A5G OPT are not wired ideally for the Omegas, they are wired for an 8ohm load whereas nominal of the Super 8 HO is 4-6ohm, which is very likely affecting low end performance.

So, that is a long way of saying, I don't know yet.

The bass/mid bass is why I love the snells. I was sort of hoping the omegas would actually give you more bass than the snells out of the box.

Sadly based on what you said, I doubt the omegas will catch up through break in which means I need a different approach.

Full range speakers very rarely have impressive bass (by my standards). And when they do, they are usually huge. Although the omegas are not a full range design no matter what they say in their marketing info. It is very much a 2 way speaker but with a little twist.

 

[L0rdGwyn]

The bass/mid bass is why I love the snells. I was sort of hoping the omegas would actually give you more bass than the snells out of the box.

Sadly based on what you said, I doubt the omegas will catch up through break in which means I need a different approach.

Full range speakers very rarely have impressive bass (by my standards). And when they do, they are usually huge. Although the omegas are not a full range design no matter what they say in their marketing info. It is very much a 2 way speaker but with a little twist.

Agreed, the bass on the Snells is really satisfying, probably my favorite thing about them too. Unlikely the Omegas catch them in that area, but they do have other strengths that make them very enjoyable to listen to, really digging them with jazz right now. Funny how I expected the Snells to be somewhat bass-light and the Omegas to be bass cannons, boy was I wrong the Omegas were ordered before I landed the Snells, so they were chosen as an "all-rounder" type of speaker. Had I heard the Snells first and knew what they brought to the table, perhaps I would have gone with what I would consider one of Louis' more specialist type of designs, like the Super Alnico Monitor. I am still very intrigued by that speaker.

 

[Tjj226 Angel]

Agreed, the bass on the Snells is really satisfying, probably my favorite thing about them too. Unlikely the Omegas catch them in that area, but they do have other strengths that make them very enjoyable to listen to, really digging them with jazz right now. Funny how I expected the Snells to be somewhat bass-light and the Omegas to be bass cannons, boy was I wrong the Omegas were ordered before I landed the Snells, so they were chosen as an "all-rounder" type of speaker. Had I heard the Snells first and knew what they brought to the table, perhaps I would have gone with what I would consider one of Louis' more specialist type of designs, like the Super Alnico Monitor. I am still very intrigued by that speaker.

I have spent years trying to find an "upgrade" to the snells that didn't cost $$$$$.

The tannoys have the upgraded sound quality I am after, but at a somewhat silly price. The frustration being that 90% of the cost is the cabinet. I know the drivers themselves don't actually cost that much. IDK why we have to pay thousands for living room art when all we really want is the sound.

High end magnepans are pretty good too AND are reasonably priced, but our poor little tube amps would choke and burn up trying to play them. Apogee speakers are in the same boat.

Klipsch corner horns are also really nice, but too expensive and too particular. If you don't have a room with two corners facing your listening chair, you are pretty much SOL.

The ultimate god tier speaker on this planet is a western electric 753C.

I just want a mini version of that. Why can't we have nice things?

 

[L0rdGwyn]

@Tjj226 Angel I was really smitten by the Tannoy Eaton earlier this year, sound comes first but boy, I am a sucker for good looking audio gear lol I love those Tannoy cabinets! They are almost too nice, I mean let's face it, your other furniture is going to look like garbage sitting next to them. Thinking of the Turnberry in particular. Maybe once I transform my home into a Victorian mansion they will blend in. A well-maintained pair of Snells is probably one of the best deals out there for low-power amplifiers. For what Louis at Omega offers - in terms of customization, product line, veneers, build quality - the prices are very reasonable, but I can't say they are an upgrade over the Snells (at least my pair), they are in the same arena in terms of performance in my opinion. Maybe that changes with different speakers in his line.

 

[L0rdGwyn]

While waiting for crossover components, speaker drivers, filament reg parts, and output transformers, I have been working on the "revamp" of my 6A5 amp.

I love the sound of this amplifier, but there are a few things I would have done differently, so I've decided to streamline things.

First off, the power tubes. The battle of the 3W IDHT titans, R120 vs. 6A5G. I spent a few days evaluating these tubes, with speakers and headphones, and my ears told me the same thing in both cases, that I prefer the sound of the 6A5G. The R120 has an interesting sound. Not quite as airy as the 6A5G, more intimate staging, emphasized low end with dynamic impactful bass, the upper midrange is somewhat forward, very nice detailed treble, it has a very fast and dynamic sound, an attention grabber. No doubt this sound has its place and another person might prefer it, but the airy, inviting, relaxed sound of the 6A5G is more to my taste. It has its fair share of dynamism and low-end kick, but just the right amount, the R120 borders on aggressive.



So, the 6A5G stays, the R120 goes into the tube archives until I dig it up again. This has consequences for the amplifier revamp. Way back, I had wanted to use voltage regulators on the 4V drivers of this amplifier, the reason being that some of the tubes in my collection have 1A heaters, others 0.65A, being able to freely swap back and forth between the two was appealing, and it still is. But alas, the 6A5G has one major drawback - due to its internal center-tap, each tube requires its own dedicated heater winding.
With two windings for the power tubes and one for the tube rectifier, that leaves one for the drivers, which will not work with my voltage regs. Changing to R120 would have allowed me to parallel the heaters and use an artificial center-tap, freeing up a second winding for my driver tube voltage regs. But the 6A5G is sticking around, so the regulators are not making it in the final build (I have weighed other options - dedicated rectifier transformer, nixing the rectifier outright, etc. - just letting it go). No big deal, a nice to have, not a need to have.

Next issue to address is thermals. Plan is to redo the chassis, add additional ventilation, redistribute/remove specific voltage dropping resistors, and change chassis-mount resistors to air-cooled through-hole. I am also leaning toward removing the combination socket and committing to 4V recitifers, giving up the 5Z3. I've found swapping rectifiers in this amplifier has subtle-to-undetectable effects on the sound. The best is the U18/20, I can't see myself using anything else at this point, FW4-500 as backup. I've changed the passive supply from a CLCLC to a CLCLCRC, the CCS loaded drivers have been moved from the first tap to the last, a more conventional layout, with plenty of headroom to drive the 6A5G to clipping and cover the droput voltage of the CCS.

Finally, I changed my grounding scheme from a conventional star ground to a distributed star ground. This is a hybrid between star and bus, in which there are local star nodes that are daisy-chained from input to output. There is a single chassis connection on the power supply cap where the two channels converge. This made no measurable difference in power supply noise, but it is more neat, and call me crazy but I feel like it improved the clarity. Hard to say, I'll just go with it



So the current amp is now something of a test bed for the finalized design that will go in a new box. These changes aren't essential, but the amp will run cooler and I feel better about the supply layout and grounding scheme. If you feel better, the amp sounds better

Three night shifts, then maybe I will be rebuilding the Snells, really looking forward to it.

 

[2359glenn]

While waiting for crossover components, speaker drivers, filament reg parts, and output transformers, I have been working on the "revamp" of my 6A5 amp.

I love the sound of this amplifier, but there are a few things I would have done differently, so I've decided to streamline things.

First off, the power tubes. The battle of the 3W IDHT titans, R120 vs. 6A5G. I spent a few days evaluating these tubes, with speakers and headphones, and my ears told me the same thing in both cases, that I prefer the sound of the 6A5G. The R120 has an interesting sound. Not quite as airy as the 6A5G, more intimate staging, emphasized low end with dynamic impactful bass, the upper midrange is somewhat forward, very nice detailed treble, it has a very fast and dynamic sound, an attention grabber. No doubt this sound has its place and another person might prefer it, but the airy, inviting, relaxed sound of the 6A5G is more to my taste. It has its fair share of dynamism and low-end kick, but just the right amount, the R120 borders on aggressive.



So, the 6A5G stays, the R120 goes into the tube archives until I dig it up again. This has consequences for the amplifier revamp. Way back, I had wanted to use voltage regulators on the 4V drivers of this amplifier, the reason being that some of the tubes in my collection have 1A heaters, others 0.65A, being able to freely swap back and forth between the two was appealing, and it still is. But alas, the 6A5G has one major drawback - due to its internal center-tap, each tube requires its own dedicated heater winding.
With two windings for the power tubes and one for the tube rectifier, that leaves one for the drivers, which will not work with my voltage regs. Changing to R120 would have allowed me to parallel the heaters and use an artificial center-tap, freeing up a second winding for my driver tube voltage regs. But the 6A5G is sticking around, so the regulators are not making it in the final build (I have weighed other options - dedicated rectifier transformer, nixing the rectifier outright, etc. - just letting it go). No big deal, a nice to have, not a need to have.

Next issue to address is thermals. Plan is to redo the chassis, add additional ventilation, redistribute/remove specific voltage dropping resistors, and change chassis-mount resistors to air-cooled through-hole. I am also leaning toward removing the combination socket and committing to 4V recitifers, giving up the 5Z3. I've found swapping rectifiers in this amplifier has subtle-to-undetectable effects on the sound. The best is the U18/20, I can't see myself using anything else at this point, FW4-500 as backup. I've changed the passive supply from a CLCLC to a CLCLCRC, the CCS loaded drivers have been moved from the first tap to the last, a more conventional layout, with plenty of headroom to drive the 6A5G to clipping and cover the droput voltage of the CCS.

Finally, I changed my grounding scheme from a conventional star ground to a distributed star ground. This is a hybrid between star and bus, in which there are local star nodes that are daisy-chained from input to output. There is a single chassis connection on the power supply cap where the two channels converge. This made no measurable difference in power supply noise, but it is more neat, and call me crazy but I feel like it improved the clarity. Hard to say, I'll just go with it



So the current amp is now something of a test bed for the finalized design that will go in a new box. These changes aren't essential, but the amp will run cooler and I feel better about the supply layout and grounding scheme. If you feel better, the amp sounds better

Three night shifts, then maybe I will be rebuilding the Snells, really looking forward to it.

What is the problem with using one 4 volt regulator feeding both 4 volt drivers. They are indirect heated so no problem.
Just use a 5 amp voltage regulator no problem.

 

[L0rdGwyn]

What is the problem with using one 4 volt regulator feeding both 4 volt drivers. They are indirect heated so no problem.
Just use a 5 amp voltage regulator no problem.

I slept on it and I am reconsidering. The regs I have on hand are from Pete Millett, and based on his spec, I would be running the heater windings slightly over current. But Lundahl is conservative with their ratings, so let's go for it. I ran it by PM too, he agreed there shouldn't be an issue.

Regulator is up and running. This setup will allow me to safely and confidently use one of my favorite tubes, the Mullard NR52. This tube has some of the deepest bass I have heard from a driver.



Another one that gets to hang out now is the Valvo A4110.



So looks like the DC heaters will make it in the revamped build after all.

 

[2359glenn]

Or build your own 4 volt regulator not that hard just need a heat sink on it.

 

[Xcalibur255]

I probably didn't do a good enough job describing or maybe didn't emphasize the point well enough in our discussions on the Omegas, but there is a certain lightness to their bass response that never really goes away. The frequency extension is there but the sense of weight and slam has a subtlety or delicateness to it that makes the bass feel less tangible. I chalk it up to the damping properties of the driver. It's probably not possible for a full range driver to have the amazing transient response the Omegas have which enables their nuanced mid/high rendering abilities and also provide any kind of visceral slam in the bass department. The laws of physics probably make this a little bit of an either/or proposition in a single driver.

Do play around with placement some more though Keenan. The Omegas are kind of weird when it comes to placement and respond differently than most speakers to room boundaries. I have mine very far out in the room out of necessity and it results in a very unique sound that I quite like for most things (but not everything). The bass is totally there and actually quite deep given it has to energize a very large room, but there is no "hit" to it as though the initial energy of the note that you physically feel is just kind of missing somehow, but the sustain/decay of the note is there to be heard. I knew going in my setup would be bass light and it is and I'm mostly okay with that, but I really thought your Super 8s would do better given how much more surface area you have on those dual drivers.

Most owners feel these speakers need a sub to be complete and they're probably right, but integrating one into what is supposed to be a "pure" nearfield stereo setup is something I wanted to avoid. I suspect it wouldn't be to terribly hard to add an active pre-amp out to your amp to drive a sub if you wanted to go that route though.

 

[L0rdGwyn]

@Xcalibur255 not a problem whatsoever Tyrell, I think you did describe the bass well to me. I know getting that type of tactile bass slam is difficult to achieve in a full range design, they have other attributes that I love which makes them very fine speakers. The bass is there and it is enough, but it is all relative, and the Snell Js just deliver a different level of density and kick to the bass. But similar to how I thought "where did the bass go?" when swapping in the Super 8s, I thought "where did the midrange go?" when swapping in the Snells. Always compromises in this hobby, I'm happy to have some variety of sound. I'll do what I can with the placement, but I am limited unfortunately. I just recently moved away from a 2.1 setup with a subwoofer, I have decided to remove subwoofers from my system, I am stricly a 2.0 guy now, keeps things simple.

On a related note, I finished one of the redone J/II crossovers.

Before:


After:


Clarity Cap CSA on the woofer, Clarity Cap ESA on the tweeter, resistors are NOS Mills non-inductive wirewound. The crossover components are extremely well-matched, so I will only have to deal with variances in the driver / tweeter units.

Still waiting on parts from Atomic Hifi. Don't say I never did anything for you, J/II.

 

[Tjj226 Angel]

Probably a stupid comment, so brace yourself.

Have you tried looking for the tweeters on ebay? I usually find decent deals on j3 tweeters. IDK about j2 tweeters.