Innerspring Mattress and Latex Topper - searching for right combo

Thank you for the wealth of information and advice provided on this forum. I am currently in the middle (and hopefully close to the finish line) of an exhausting and frustrating mattress buying quest, and hoping you could provide some insight and recommendations as to the best mattress/latex topper combo.

A little history - finally gave up a 15 year old mattress which was sagging, to which I had added a memory foam topper - worked for quite a while, but my issues of left sided pain - hip tendinosis, sciatica, scoliosis had caught up with me and I needed to start over with something new - I am a back sleeper, am 5’1 and about 95 lbs. It was recommended that a fairly firm mattress with a latex topper would provide the support and cushioning I needed. Sounded good to me.

Anyway, several months and (big retail name) mattresses later - I currently have a Beautyrest Recharge Classic Flatbook (Firm) which seemed OK in the store ( I knew it was too firm to sleep on directly, but planned to add the latex topper). However, the one delivered is MUCH firmer - there is no give whatsoever, and it is like sleeping on a board. I placed a 2" Talalay soft latex topper (from another room) on this mattress and have given it three weeks (I do have a comfort guarantee of 30 days one exchange available) I can manage to fall sleep with a pillow under my knees and hips, but wake up in terrible stiffness and pain. Cannot believe that with even the topper, I feel nothing but rock hard layers beneath. I feel as if I need to put more “fill” into the curve in my back, and the latex is not enough.

To add to the confusion, I re-read the specs on my mattress and have come to realize that the retailer I purchased from calls this a Firm, but it actually matches the specs of the Flatbrook Extra firm (from many other sources). So no wonder it feels like a board. I know retailers can change names and such, but to market it as Firm, when it is clearly Extra firm doesn’t really help the customer.

Here are the specs:

Quilting: 1" AirCool Foam
1" AirCool Foam
1.25" Celestra

Comfort Layers: 0.5" Gel Touch
0.5" AirCool Memory Foam
1" Energy Foam (which is apparently firm foam)

Coil Gauge: 13.75
Coil Count: 800

In doing more investigating, I discovered that this retailer also carries what they call the Flatbrook “Plush”, which I would normally never consider, but it actually matches the specs for the “Luxury Firm” - which sounds more like what I was expecting.

The specs for this mattress are:

Quilt Layers - the same as above

Comfort Layers: 0.5" Gel Touch
0.5" AirCool Memory Foam
2" Plush Comfort Foam

Coil Gauge: 13.75 (I confirmed this - it is not the 15.5 that is really on a plush model, but this is still firm)
Coil Ct: 800

I think this is my only choice for an exchange - I want to stay with Beautyrest because it compares favorably to the others I have tried, except for how hard this is. Do you think that the 2" of plush comfort foam in this version would make the difference and give me more comfort at top, without it leading to deep saggin (which I have been afraid of all along)

Also, why do you think the latex topper is not working with the mattress I have? because it is too firm? I feel it is not keeping me “lifted” but sending me straight down to the hard innerspring layers. Do you think if I exchange to the “luxury firm” mattress in combination with the current topper that would work to provide support without sinking through, or am I too light for this combo? I feel “everything” and since I am a back sleeper, feel pain along the mid back, spine, etc.

I should add that the latex topper works fine with another year old mattress in the home (it is a Sealy Posturepedic Firm - but no longer available in the store) - I have tried that combo with no pain - the latex feel cushiony and supportive and I can even feel my back relaxing. It feels wonderful, so I know there is hope. However, as soon as I put it back on the Beautyrest, all my pain points fire up and it feels completely different. I really would like to use the latex, since I don’t want memory foam anymore - am concerned with chemicals, smells etc.

Also, would I be best to consider a 3" latex topper vs the 2" or would I sink even more?

I’ll have to go back to the store in the next few days to start the exchange process, but was hoping that you might be able to provide some guidance and wisdom.

Thanks very much.

Hi BetsyBee,

It’s not unusual at all for a new mattress to feel very different from what you tested in a store. Part of this can be subjective (even testing many mattresses on the same day can change your perceptions and most people have had the experience of testing mattresses over the course of a day and then when they went back and re-tested the mattresses they started with they felt very different).

Part of this can also be objective because all new mattresses will go through an initial breaking in period which in some cases can take a few weeks or even months. With your lighter weight and with a topper on top of your mattress it could take even longer. Sometimes walking on your mattress evenly across the surface over the course of a week or so can help speed up the break in period.

I don’t know the specifics of your mattress (Simmons doesn’t disclose them) but you would likely need softer foam in the comfort layers or with a topper to allow your lighter body type to sink in far enough to fill in the gaps. Depending on your body type and sleeping positions you may also need more thickness (possibly closer to 3") to fill in the gaps and isolate you from the firmer layers underneath.

Firmness ratings are very subjective and vary based on individual perception, body type, and sleeping style so what is firm to one manufacturer or person may be rated differently by another manufacturer or person. There is no “standardized” rating system for the perception of firmness or softness and only personal experience can really know what feels firm or soft for each person. There are also different types of firmness and softness and each person may be referring to something completely different even though they are using the same word (see post #15 here). Someone for example that was very heavy may feel that your mattress is too soft. These are all very subjective ratings and at best … the firmness ratings in a store are approximations and at worst … they may be little help at all.

The “good news” is that it’s easier to “fix” a mattress that is too firm than to firm up a mattress that is too soft which would involve replacing or exchanging layers instead of adding layers on top.

While I certainly don’t agree about how Simmons (or any major brand) compares to other better quality mattresses … if you only have one exchange I would completely avoid analyzing the specs (which aren’t available to you anyway because they don’t disclose the quality specs or the comfort specs of the foams they use) and focus instead on very careful and objective testing for PPP (Posture and alignment, Pressure relief, and Personal preferences) following the testing guidelines in post #1 here. This would give you the highest odds of making the choice that was most suitable for your body type, sleeping style, and weight even though you still wouldn’t have any information about the quality or durability of the materials. The comfort layers of the major brands generally use lower density/quality foams so the chance for sagging over the longer term would be higher with thicker layers of soft lower density foam yes. This is difficult to avoid with any major brands though because they are mostly the same and none of them disclose the specs of the materials they use for the most part. Your lighter weight is an advantage here because you won’t be as hard on a mattress as others that weight more and a topper can also help slow down the softening or sagging of lower density foams underneath them.

If I had to guess it would be that the topper isn’t thick enough to keep you isolated from the firmer layers below. I don’t know the ILD of your topper so I can’t speculate on its softness although with your lighter weight I would suspect that it may also be too firm. There are some topper guidelines in post #2 here and the posts it links to that may be helpful as a reference point.

Do you think if I exchange to the “luxury firm” mattress in combination with the current topper that would work to provide support without sinking through, or am I too light for this combo? I feel “everything” and since I am a back sleeper, feel pain along the mid back, spine, etc

There is no “formula” or 'theory" that can predict what someone else will feel or experience on any specific mattress because it depends on how every layer and component interacts with every other layer and component and the specific body type and sleeping style of the person on the mattress. This is especially true when most of the specs about the materials in your mattress are a mystery and aren’t disclosed (Simmons doesn’t disclose the specifics of the materials in their mattresses). Your best odds would be very careful testing for PPP that is as objective as possible rather than trying to analyze specs (such as coil gauge) that have little meaning by themselves. All that you can know is that 15.5 gauge coils are softer than 13.75 gauge coils but this still won’t tell you how the other layers on top will interact with the innerspring or how the mattress will feel and perform for you.

This is because it is on top of a different mattress with different comfort layers and a different design. How a topper feels will depend on the mattress it is on because every layer in a sleeping system affects and interacts with every other layer. This is especially true when the top few inches of each mattress are different. Again though … none of the major brands disclose the specifics of their materials so you would be left with going by careful testing because the specs you have available are not complete enough to use as an effective guideline or reference point to make your choice.

Hopefully this will help or at least provide some insights but my guess … and it’s a guess in the absence of most of the information I would normally need to even make a guess …is that you probably need a thicker and possibly softer topper.


Hi Phoenix,

First, thank you so much for your very detailed and thoughtful insight into my specific situation (as well as so many others you have helped).

I am following up on my first post from a few months ago at which time I was dealing with a too firm new mattress purchase at a major retailer and had the opportunity to make a comfort exchange – and hopefully find the right topper to soften the surface.

I wish I had found your site prior to my ongoing mattress quest, but since I was stuck with only selecting from the big mattress companies, I did follow your advice as much as possible and exchanged the Beautyrest firm for a Sealy firm queen (which actually felt a tad bit more comfortable, and so I was hoping would work better with a latex topper.) I ruled out any mattresses that were plush, even though they felt more comfortable in the store, and tried to select the best of the worst.

I realize from your advice that the weakest link will be the polyfoam layers on top which are most likely of lesser quality – but my goal is to get the topper that works the best in conjunction with this new mattress. I already had a twin Talalay latex 100% natural topper 2" that provides pressure relief when used on a different firm Sealy bed, but was not as comfortable on my firm Beautyrest (before the comfort exchange). You had mentioned that at my light weight and body frame, I would probably need a thicker and softer topper. You had guessed that my 2" topper was probably too firm - I wanted to let you know that the one I just referred to was in fact a “soft” which translated to a range of mid-teens ILD, so I guess it was pretty soft.

After reading and learning from you and the discussions on this site, I contacted Brooklyn Bedding and spoke to Mario regarding their latex toppers, as I know you have recommended them as a reliable supplier. He advised similarly that at my lighter weight, I would need a thicker topper that was in the soft range and recommended that the one I should order was their 3" 19 ILD Talalay topper (they call it ultra plush), which I ended up doing so.

I’ve had the topper since the beginning of September and unfortunately, it is not doing the job of providing relief and comfort for me at all. Although it is 3", I am wondering if the fact that this is a blended Talalay, vs the 100% natural that I have on the other bed – is giving a more firmer feel, plus the bamboo cover, which is NOT removable, may be adding to the fact that I don’t feel the latex spongy feeling as I do with the all natural 2". I realize now that I am probably comparing apples to oranges—in that the materials are different and perhaps the cover is muting the more resilient effect of the latex. The BB topper is a lovely product - looks and feels upscale to the touch, but sleeping through the night on it is another thing altogether. The natural topper I have does not come with a sewn cover, so I had just put on a fairly thin mattress pad, which allows me to feel the latex more directly.

Basically, I sleep on my back all night and am not sinking in enough (lower back or shoulders) to feel any cradling effect. I now have newer pain in the morning – my shoulders and neck, back of head are also stiff and everything in that area hurts – I am trying to find the right pillows to work with this topper/mattress combo, but to no success so far. So it seems as if I have not only failed to provide the comfort and pressure relief on my spine but created upper back and “above” pain as well. I am starting to lose hope that I will ever feel better in the morning. The intense pain upon waking does subside somewhat during the day, but I know how important it is to have a quality night’s sleep and I worry about the long term effects on my overall health of dealing with this on a daily basis.
I’ve gone through 5 new mattresses in this 6 month search and was optimistic that buying a firm one plus adding a latex topper would be the right move. I have since learned that I am not the “average” person in that I am too small and light for these general recommendations to work perfectly. I thank you for your earlier guidance as it has helped me to understand how the layers interact, etc. For now, I am stuck with the mattress, so I want to do whatever I can to make a topper work for me.

I put the 100% All natural talalay topper 2" – Soft on this new bed (from the other room) and while not perfect, does a MUCH better job of cushioning me and softening the surface than the 3" 19 ILD from Brooklyn Bedding, which seems resistant to my body pressure. Ideally, I would probably do best with a 3" all natural soft, but BB sells a different product. BB does sell a 3" 14 ILD (very soft), but again, it is a different composition - ie. Blended – and maybe I am just too sensitive to handle anything but the more natural product. I have not yet contacted them but know that they offer exchanges – I just think I made a big mistake and would hope that I could return this topper and start over with a 100% natural product. What it boils down to is that I feel better with the 2" natural topper “soft” than with this 3" Blended topper ILD 19.

Phoenix, I did read your earlier explanations of blended vs natural, and understand that there could be subtle differences – maybe not felt by most, but apparently, me – do you think that is what is going on here? I am afraid to try the 14 ILD from BB (they call it super soft) and find that it is not the right thing either, and then the saga continues.

I would appreciate your thoughts on how best I can proceed with things. I need to contact BB at this point but am so confused as to what would really work for me, given what I’ve tried and failed with. I know you can provide more clarity for me. Thanks so much.

Hi BetsyBee,

To make any meaningful comments I would need a little more information from you …

Are you certain your topper is 100% natural Talalay and what is the softness rating? If it’s blended Talalay from Latex International it will have an actual ILD rating (14, 19, 24 etc) and if it’s 100% natural Talalay it will have a rating that starts with an “N” and has a number after it (probably N1 or N2). 100% natural Talalay doesn’t have a specific ILD rating. Is the Talalay from Latex International?

This would probably have less to do with the type of talalay and more to do with the relative firmness and thickness of each topper. Blended Talalay is actually less dense than 100% natural Talalay and in the same ILD would be a little bit softer and more pressure relieving than the 100% natural because it doesn’t get firmer as quickly as you compress it and sink into it more. 100% natural Talalay is a little bit more “supportive” because it firms up more quickly. Covers will have some effect on the compression of the latex but a thinner stretch knit cover will have less effect than a thicker cover or one that isn’t as stretchy.

What type of mattress pad is this? A mattress pad … even a thin one … will generally have a bigger effect on the latex underneath it than a cover that is typically used with a topper.

Where is the intense pain … in your lower back or in your upper body or both? I’m not quite clear on the actual symptoms you are experiencing with each topper since you’ve had your new mattress.

Again without more specific information it’s not really possible for me to make meaningful guesses but this does point to the possibility that you may need a softer or thinner topper if the one that works best is softer (which you would still need to confirm) and thinner. Again all of this would vary with the mattress so when you change the mattress you are really starting all over again with a topper as well because a topper that works well on one mattress may not work as well on another mattress that has a different design. The thinner topper may be doing a better job of keeping you in alignment (which would make sense for a back sleeper) rather than “cushioning” you because a thicker topper would generally provide more cushioning unless it is significantly firmer than the thinner topper.

No … I think that what you are experiencing probably has more to do with the difference in the softness and thickness of the toppers, possibly the mattress pad, and possibly the cover, than with the type of Talalay although that may be playing a minor secondary role.

If you can provide some of the missing information about your 2" topper, the mattress pad you are using, and more specifics about the type and location of your “symptoms” (without regard to whether it “feel like” you are sinking in too far or not enough because this is just a subjective “feeling” and actual symptoms are a better way to make more meaningful assessments) it would be helpful in guessing at the next option that has the highest odds of success.


Hi Phoenix,

Thanks for writing back so quickly – here is the information regarding your questions:

The 2" topper was purchased from the Mattress Expert and Pete advertises it as pure latex, no synthetics, fillers, etc and that it does come from Latex International – when asked the rating, he says it is “soft” and would correspond to an ILD in the mid teens, although as you pointed out, it would not have a specific ILD rating. He does not provide any further info. (i.e. an “N”)

The mattress pad I am using on the 2" is a Therapedic “Pure Sensation” from Bed Bath & Beyond – it indicates it is 100% polyester fiber batting. I had purchased a previous one from Costco that was way to poofy/bumpy and I actually felt the ridges in the padding, so this one seemed less bumpy and it actually can fit over the thicker mattresses ( my new mattress is now 12.5" + 2 or 3 " of topper). Based on this pad, am I creating more problems and if so, what would they likely be?
What would you recommend if this is not a good choice?

As to symptom location: The new intense pain/morning stiffness now centers all across my mid back area (more specifically around the “bra” line) – but then I’ve also developed neck/shoulder stiffness (I actually have trouble raising my head up and down) – symptoms I’ve never had before the new mattress and topper combos. I’ve always had sciatica and left sided hip stiffness, but these issues are better managed than before and I do sleep with a pillow under my knees to take the pressure off my lumbar area. I would say that it is basically now a mid to upper body issue – regardless of the mattress or topper (and never had this with my old mattress/memory foam topper. Perhaps I just became used to that combo, but I never had trouble with the upper areas like I do now.

With the 2" Natural configuration, the intensity of the stiffness in my back is a “little” less than with the 3" blended. The neck/shoulder pain is also not as intense as well, but it’s definitely there.

Just to get back to the 2" vs 3 " – I thought that generally a 3" is recommended for someone petite like myself. I remember you had said that a 2" layer will compress to a larger percentage of its thickness and we would generally feel more of the layer below, so even though, of the two I am comparing right now, the 2" natural produces less intense symptoms than the 3" blended, but I can still feel firmness below – it is just that the newer upper back symptoms, especially pronounced with the blended, are more worrisome to me.I think you had said that upper back pain was more indicative of too firm layers, so is that possibly still the issue?

It looks like a 2" could put me closer to the firm layers below but keep me in better alignment, while a 3" provides more cushioning but could be worse for alignment ? Not only am I a back sleeper, but I generally do not move much at all during the night - in the morning I might go over to the side, just to stretch out before getting out of bed. So I guess the potential for stiffness is greater since I am in one position all night.

I didn’t realize that the natural would actually firm up more quickly and so the blended would actually get softer - I seem to be having the opposite reaction, except that you think that the thickness, and mattress pad/cover issue could also be affecting my perceptions as well, is that correct?

I do realize that I indeed “started over” with a new mattress, though it is probably almost as firm as the previous one, so I may not have accomplished all that much with the exchange. However, the Beautyrest was like sleeping on the floor, so perhaps I made an incremental upgrade.

Hopefully I’ve provided the missing information you’ve requested and look forward to your thoughts about the best way to go from here.

Hi BetsyBee,

It would be helpful to know whether your 2" topper was an N1 or an N2. This would provide a reference point. If it’s an N1 then it would be softer than 19 and if it’s N2 then it would be firmer than 19.

From your description it appears that it’s probably softer which may indicate N1 (which would be mid teens) which means that your 3" topper is firmer than your 2" topper but of course thickness is just as important a part of how a topper feels and performs and thicker toppers feel softer than the same ILD in a thinner topper.

If you are having mid to upper back issues this generally indicates that either your sleeping surface is too firm and is putting direct pressure on the back muscles or that it’s too thick or soft which may be causing you to sleep in a position where your shoulders are pushed forward (shoulders not sinking in as far while the mid body sinks in further) or in a hunched position similar to if you push your head forward and your back is rounded. If you are not moving and changing positions over the course of the night then this can contribute to stiffness as well (the body generally needs to move am least a dozen times a night). The first would be a pressure issue that would generally need a softer surface and the second may be an issue that your topper is too thick or soft. With 3" of 19 ILD blended Talalay it’s not likely to be a pressure issue (this is fairly soft) so I would guess that it may be a thickness issue.

The mattress pad you have would also interfere with the ability of the latex to contour to your body and for the lighter parts of your body to sink into the latex which could also add to alignment issues and I would remove it at least for a while to see what difference it makes.

Yes … this is the general idea … and back sleepers generally need less thickness than side sleepers and lighter weights generally need softer toppers than heavier weights.

So overall if I am understanding you correctly …

With the 3" topper you are experiencing upper body pain?

With the 2" topper you are experiencing less pain but in the same places?

This also points to thickness and alignment being the issue.

More for side sleepers than back sleepers. The back is a “flatter” position than the side and doesn’t have the bony prominences like the shoulders and hips that need to sink in more for pressure relief so side sleeping generally needs thicker layers than back sleeping and stomach sleeping needs the thinnest layers of all.

The difference between blended and all natural is not nearly as significant as the difference in firmness levels and the difference in thickness between your toppers.

I think the next step I would take is to sleep on both the 2" topper and the 3" topper without the mattress pad and then try and identify how much difference it makes and which of the 4 combinations is the best for you (both toppers with and without the mattress pad). I would sleep on each of the two new combinations (without the mattress pad) for a minimum of 3 nights if possible.

It may also be worth trying to sleep on just the mattress alone if you can to see what kind of changes in your “symptoms” that produces as well so you have one more reference point.

Just to eliminate other possibilities as well … do you have any other types of bedding on the mattress besides the sheets such as a mattress protector?

What kind of foundation are you using?


Hi Phoenix,

I have an update but wanted to answer the questions you asked me in your last post.

I’m pretty sure that the natural latex topper is probably an N1 since it was told to me that the ILD would be in the “mid teens.”
The foundation is a matching box spring low profile from Sealy.

Your assessment of my experiences on each topper is correct.

The 3" blended gives me a more pronounced mid back pain – in the last week I’ve noticed that I do feel as if I am sinking too much in that area (causing a rounded back feel) and that it might be that the topper is actually too thick and/or soft causing me to have more sinking in the pelvis vs the shoulders, which are not getting cushioned. I’m feeling more that it is like a “hammock”. The 2" natural was not as pronounced. – which goes to your suggestion that thickness and alignment may be the issue here.
(Unfortunately, I am not able to further test the natural as I had to return it to a different room for a family member.)

As for mattress pad, the 3" blended from BB came with a non removable bamboo cover – so I have not been using an additional pad on that one. Was your suggestion to add the pad to the already covered topper? The mattress pad I have been using was only placed on the 2" natural. I know you said that the pad can change things – if I were to add the pad onto the already covered topper, what type of effect would I be looking for or likely to experience? A firming up of the thickness/softness so I might not sink as much?

Now to my update – I contacted BB and told them of my pain/discomfort issues with the 3" blended 19 ILD – they do not offer a return, only a one time exchange. (so I can not move forward with any comparisons to the natural product that I would prefer).

Mario felt that my problem was the topper was too soft and I was going through the topper and feeling the firmness of my mattress below. He advises that I exchange it for a 24 ILD but still in a 3" thickness. At first I was pretty surprised, as I thought my mattress was too firm and why would I want a firmer topper – I questioned that perhaps I needed the 14 ILD, but he said I would go through that even more an advised against that. I also asked about the merits of a 2" vs a 3" but he still thinks I should stay with 3".

Now I am more confused – since I spoke with him I have had a few more nights to try to figure and test things out, and the feeling of “sinking” is definitely more pronounced and I think my upper back muscles are struggling with the alignment. I notice that when I try to sit up in bed (when reading), I am sinking down deeply which feels totally uncomfortable and unnatural – again, the hammock feel – no support at all. Starting to feel like a jello top on a firm mattress below.

As a reference point, when I tested the 2" natural on my mattress last week, I did not sink nearly as much, especially when sitting up in bed.Does this clearly point to the thickness difference or still the material? I know you feel that the natural vs blended is less of an issue, so that leaves ILD and thickness.

Mario said that 24 ILD is not considered firm, still “soft” but would do a better job of preventing me from going through but I wonder then why the 2" natural (with probably an ILD in the low-mid teens) did not produce that effect. Again, for me this comes down to the material as well. Unfortunately, I have to forget about the natural but just mentioning it as a reference point.

Basically, I am left with just these options – exchange the 19 ILD 3" for:

24 ILD 3" - Mario’s recommendation – does not address the thickness which you and I probably think might be a more important consideration than he does.

24 ILD 2" - better for alignment but am I going too firm with an already firm mattress?

19 ILD 2" – keep the same softness but will the thinner layer do a better job of keeping my from sinking and going out of alignment, or would I go through even more since it puts me closer to the mattress?

Finally, since my “Ideal” was the 2" Natural, which if any of the above choice would come closest to approximately that?

I was told that I can order the new topper which would be shipped to me and then I can try them both out before deciding which of the two to send back. So with my “one last” opportunity to get this mattress combo right, I would like to make the best possible selection. I am feeling like I am rolling the dice, because I won’t be able to know for sure until I try it out, but I would appreciate your advice as to which of these options might be an “upgrade” in terms of correcting the current topper problems.

PS - One other thing to mention - when I started added a small, thin microfiber (not sure of the exact material) quilted blanket under my back as an additional comfort layer over my sheet, I noticed that it kept me more aligned and I had less of a sinking feeling, with a nice softer feel as well. If that helps the current 19 ILD 3" - what do you think that means in terms of what would work best ?

Thanks so much for your help!

Regarding the 2" topper, if the LI product is similar to the Pure Latex Bliss that LI produces and they follow suit as they do with their PLB blended/all natural talalay, the topper would be N1. Just saw this thread and don’t know if information is too late to be of use.

-Jeff Scheuer
Mattress To Go

Hi BetsyBee,

The suggestion was to make sure you eliminated the effect of the mattress pad as a variable. Some mattress pads … especially if they have some padding like polyester batting (vs a mattress protector which has no padding and is generally thinner and more stretchy) … will reduce the ability of the softer layers below it to contour to your body and create a firmer feel. It also depends on the type and thickness of the mattress pad and on the firmness/softness of the foam underneath as well but either way I wanted to make sure you had tested both ways because if removing the mattress pad makes a positive difference then replacing the pad with a thinner stretchy protector could help.

As I mentioned in some recent posts here and here … welcome to the world of contradictory suggestions (see post #8 here as well) :).

When a top layer is softer … you will “feel” more of the firmness of the layer below it and/or the transition between the layers. To exaggerate the idea a bit to make the point … if you imagine a 3" layer on the floor you will probably feel the floor below you and if you use a softer layer you will sink “through” it even more and feel more of the floor so it would feel firmer. If you were to use a firmer layer it would isolate you from the floor more and for many people would feel softer. Sometimes mattress design and theory can seem counterintuitive until it makes sense.

If the firmness someone feels is coming primarily from firmer layers underneath a topper (which depends on how far they are sinking in) … then using a slightly firmer layer can feel softer but it will also reduce the amount your lighter shoulders can sink into the upper part of the mattress.

In your case though (based on speculation) the issue seems to be more of the alignment in the midback or upper back area possibly from sleeping in a hunched or rounded position more than a pressure issue. I’m not so sure that you are feeling the firmness underneath your topper because even in a firm Simmons mattress there is some soft foam in the comfort layers before you reach the firmer layers underneath and with your lighter weight you wouldn’t be as likely to “go through” a topper and the softer comfort layers in your mattress to feel the firmer layers underneath this.

With all the back and forth theorizing and speculation this is perhaps the most important part of your feedback and a good reference point that is worth “listening to” because it’s based on your actual experience. If your 2" topper was N1 (which based on the information Pete provided it likely was) then it would be firmer than a 2" blended Talalay in the same firmness level (blended Talalay is a little softer than 100% natural Talalay in a similar ILD because it’s denser and you don’t sink down as far). Depending on the exact ILD of the 100% natural topper (which isn’t exact) … it would probably be in between the 14 ILD blended Talalay and the 19 ILD. In “real life” though it’s probably a little closer to the 19 ILD because you sink into a top layer more deeply than if the layer is deeper in the mattress and blended and 100% natural latex gets firmer when you sink in deeper at different rates. 100% natural gets firmer faster and while the 19 ILD blended would start off a little firmer with more shallow compression, it wouldn’t get firm as fast when you sink into it more so the differences in their initial firmness would tend to even out with deeper compression.

Mattress design and theory is partly art and partly science and with more complex circumstances like this where the specifics of your mattress that’s under the topper aren’t known, it’s more art than science. This means that each version of contradictory ideas may turn out to be valid. So all of this is still speculation based on your experiences and feedback (as complex as it is) with lots of guesswork involved so your own best judgement and “gut feel” will really be the only way to decide. Sometimes there is no alternative to some trial and error because in the end only your own personal experience will know what ends up working best for you because there are always variables and unknowns and bodies don’t understand “theory” … only results.