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Audio First Fidelia on Erin’s Audio Corner

With all due respect none of this info is particularly relevant to the topic. The topic was really which bookshelf will perform better, the 1tdx or the fidelia. The answer is objectively the fidelia. Based on the research we have on listener preferences most user would prefer the fidelia.
Sorry? We?

To the best of my knowledge only Erin has done a review of the Fidelia and I don't believe he did a review of 1-TDX. ( I couldn't find one... and it seems he's the only guy not to review it. ;-) )

We can look at the videos showing the actual builds. (CSS and Audio First both have videos on the build process.)
In terms of the Klippel ?sp? output we only have Erin's Fidelia.

W.R.T bookshelf kits there are a couple of factors. (Size, cost, and ease of build.)
As I pointed out... watching the video of the Fidelia build you can see the tear out issue. If you look at the design this could be due to the quality of the plywood, or how the panels were cut.

If you look at the XOs, both are using quality components. The CSS has two different levels in terms of components so you'd have to consider which one matches the Fidelia. Also I believe there's a difference in size.

Now to be clear, I'm not bashing the Fidelia or promoting the CSS.
I was just asking if there was a comparison because they are both around the same price.

Note: The tear out would be on the back of the speaker, although it could also be on the top due to the exposed edge grain. The front baffle looks to be either molded or printed plastic w the drivers mounted to the wood front panel behind it. The CSS cabinet doesn't appear to have this issue.

And to be fair, this is AudioFirstDesign's first product offering. He's a one man shop and still has some kinks to work out.
(Sourcing of the flat pack material for example.)
He was smart to go to Erin. Erin is honest and if he likes something... there's a reason for it.
 
...I couldn't find any reviews by Erin for CSS
You may already know, but Amirm has reviewed two of the CSS speakers here on ASR. I'm not linking since this is the review thread for the Fidelia but you can find them if you are interested.

The baffle with built in waveguide is a very cool feature of the Fidelia and sets it apart from a typical kit. Kudos to the designer.
 
To the best of my knowledge only Erin has done a review of the Fidelia and I don't believe he did a review of 1-TDX.
Amir measured the 1TD-X and you can find that data on spinorama.org. Erin's measurements of the Fidelia should be on that site soon and then you can directly compare the objective performance of these speakers for yourself. I have not heard either speaker but based on the measurements I would definitely choose the Fidelia.
 
Amir reviewed the 1-TDX right here.

1TDX:
1733336766755.png

Fidelia:
1733336882845.png


If we go with the general criteria that smooth, flat frequency response and smooth directivity are better, then the Fidelia is the better speaker in objective terms.

This is not to assert that you personally will prefer the sound, but the research @Ktacos refers to does suggest the average person would prefer the Fidelia.

Here's my personal, opinionated evaluation of the available data: The Fidelia is obviously better than the 1TD-X. It's slightly more sensitive, the FR is clearly smoother, it doesn't have significant directivity errors (no waveguide in 2024 = a miss), the top octave is actually under control and it has just as much bass extension.

It costs a little more for a comparable kit, but IMO it's very stiff competition for the 1TDX. I think it's a valid comparison to make in the thread, there aren't a ton of high-end mainstream kits like this. That said, I don't want to turn this into a "dunk on CSS" thread or anything like that. Let's note that Amir recommended the CSS kit in his review. I am not suggesting and nor do I think anyone else is suggesting the 1TDX is a "bad" speaker.

This just goes to show that the Fidelia is a very exciting addition to the DIY space. It's got basic performance comparable to a Genelec 8030 for less than half the cash, probably about half once you get an amp or two involved. Pretty remarkable.
 
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You may already know, but Amirm has reviewed two of the CSS speakers here on ASR. I'm not linking since this is the review thread for the Fidelia but you can find them if you are interested.

The baffle with built in waveguide is a very cool feature of the Fidelia and sets it apart from a typical kit. Kudos to the designer.
Not all numbers are the same.
AFAIK Amir doesn't have a Klippel.

And again, the question was a comparison between CSS and the Fidelia. No one has reviewed both and taken measurements.
I mean I can point to the graphs on the CSS site and say look at how flat they are... but that's not going to mean a hill of beans.

Your 'objective' is a bit subjective.
You can compare and contrast the builds and design choices... but there is no 'we' or a consensus in terms of reviews.
It would be having either Jay Lee or Ron at NRD talking about CSS vs G R Research because they have reviewed both.

This doesn't take anything away from the Fidelia and I think its one worth looking at.
 
Thanks. I stand corrected on Amir having a Klippel.


Looking at his review:
"The CSS Criton 1TD-X design has benefited from some good design choices such as a woofer with impressive power delivery with good on-axis and predicted-in-room frequency response. There are minor imperfections here and there but at higher level, it achieves very good fidelity. Subjective experience with a bit of filtering was very good. As a kit, it will give you the satisfaction of building something you can take pride in."
Ok, outside of the EQ he points out a weakness in the CSS which is the cabinet resonance.
Looking at the Fidelia, there is more bracing. In fact its the back of the speaker which has an issue where he cut out space for the back panel. This is the area that got tore out.
So its a bit of a trade off. Had he used HDF or MDF for the cabinet, that wouldn't happen. It doesn't impact the sound, but its an aesthetic issue.

The nice thing about the kits is that you can modify them if you know what you're doing. CSS sells the kit w/o a flat pack so that you can design your own box as long as you don't change the size and shape of the baffle.

Again, I'm not knocking the Fidelia, just comparing it to another kit.
Honestly if you're in the EU, the Fidelia is a better option simply because of the cost of shipping.

W.R.T the data...
While I respect both Erin and Amir... its not the same if Erin reviewed the Fidelia, and Amir the CSS or vice versa. Two different people, two different reviews. There's an objective and subjective part.
Its when you have the same person reviewing both speakers... also if you have a gaggle of reviewers w a consensus of opinions.

The reason I wanted to compare the two is that there are design choices that have been made and this leads to different outcomes and issues.
 
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It costs a little more for a comparable kit, but IMO it's very stiff competition for the 1TDX. I think it's a valid comparison to make in the thread, there aren't a ton of high-end mainstream kits like this. That said, I don't want to turn this into a "dunk on CSS" thread or anything like that. Let's note that Amir recommended the CSS kit in his review. I am not suggesting and nor do I think anyone else is suggesting the 1TDX is a "bad" speaker.

This just goes to show that the Fidelia is a very exciting addition to the DIY space. It's got basic performance comparable to a Genelec 8030 for less than half the cash, probably about half once you get an amp or two involved. Pretty remarkable.
Thank you.

This is the discussion I wanted to have and see.
From Amir's review there is an issue w the box having some resonance. They made a trade-off in ease of build vs more bracing.
Note that CSS offers the flat pack in both MDF and Birch Ply. Not sure if that would make much difference in terms of resonance. (Additional bracing would.)

Would also like to know more about the Fidelia's tweeter. CSS makes their own drivers. So its interesting to see the issues on the top.

Its important to point out that both CSS and the Fidelia have what looks to be good components in the XO.

I don't know if I'd say these were 'high end' kits. You can go to Madisound and see some 'high end' kits. And to be clear... these kits are a great value and good kits.
And very similar. Hence the comparison.

If you went the plans route... you can see some Troel's plans for the Purifi and different tweeter options. (Including using Purifi PRs instead of a port)
(But that would probably be more money in parts alone... ) And this is outside the scope of discussion.
 
Fortunarely, both Amir and Erin have helped educate us on interpreting speaker measurements. They have proper credentials.

Its quite obvious why so many are excited about Audio First Fidelia. And thanks to others for repeatedly highlighting why its better than other available diy kits. @im_gumby, you have really shown why the its a superior design to CSS

I have not dabbled in diy since Linkwitz designs, but this has now got me curious.
 
While I respect both Erin and Amir... its not the same if Erin reviewed the Fidelia, and Amir the CSS or vice versa. Two different people, two different reviews. There's an objective and subjective part.
Yes, but I tend to ignore the subjective stuff and just look at graphs. Whatever their opinions are, we have reliable hard data we can compare. And, as far as we know, Amir and Erin's klippel setups deliver basically the same results. AFAIK when they measure the same speaker it is rare to have more than a couple +/- 1dB variances in their results. These Klippel things get talked up with good reason.

I don't know if I'd say these were 'high end' kits. You can go to Madisound and see some 'high end' kits. And to be clear... these kits are a great value and good kits.
And very similar. Hence the comparison.
Fair enough, one man's high-end is another man's bargain basement. I guess when I say "high end" I mean the priority seems to be good or even excellent performance within the bookshelf category, not just saving money.
 
i would paint it and coat it to something like this perhaps (dyn audience52), or just keep it like it is (dyn special25 look)
20241204_234125.jpg


i am seriously thinking of buying this kit, i only would like know (from crystal ball -i guess), that there will not be another version with 6.5" woofer or better yet twin woofers in-the-works, that would really bum me out :oops:
 
Fortunarely, both Amir and Erin have helped educate us on interpreting speaker measurements. They have proper credentials.

Its quite obvious why so many are excited about Audio First Fidelia. And thanks to others for repeatedly highlighting why its better than other available diy kits. @im_gumby, you have really shown why the its a superior design to CSS

I have not dabbled in diy since Linkwitz designs, but this has now got me curious.
Thanks.

I think this kit solves some of the issues that CSS faced. (But still has some issues of its own.)
They've done a couple of interviews and I think if you see the YT video of their collaboration w Jay Lee you can see where they talk about the speaker design being a trade off and compromises. (In one of the segments they talk about XO components where they went uber expensive and built a killer XO for testing...)

And CSS isn't standing still.
They just did a limited run of the kit using a tweeter w a wave guide w a MDF flat pack.
And I think they were experimenting w different cabinet materials.
Also one of the guys just did a video where he built a custom speaker using other drivers in addition to what they offer as a side project.

There is nothing stopping them from creating a waveform baffle out of plastic like the Fidelia. I mean he must have done a bit of experimenting w 3D printing before getting a design that he could then stamp in plastic.

I think the competition in this space makes everything better.

Since you can buy the CSS kit without a flat pack, I know that you can get the plans. If you have access to a CNC router you could make your own cabinet and fix some of their issues. Also use different material. Like Richlite. (Although the cabinet would cost more than the XO and Drivers. )
 
Yes, but I tend to ignore the subjective stuff and just look at graphs. Whatever their opinions are, we have reliable hard data we can compare. And, as far as we know, Amir and Erin's klippel setups deliver basically the same results. AFAIK when they measure the same speaker it is rare to have more than a couple +/- 1dB variances in their results. These Klippel things get talked up with good reason.


Fair enough, one man's high-end is another man's bargain basement. I guess when I say "high end" I mean the priority seems to be good or even excellent performance within the bookshelf category, not just saving money.
Yeah, and you need to be careful... its a rabbit hole.
How far do you want to go?
PartsExpress has kits that are reasonably priced. Madisound and Solen (Canadian) have more expensive kits.
Someone said Fidelia uses SB Acoustics speakers. Take a look at some of their (SBA) kits.
Then also look at SEAS. Do you want active or passive XOs?
My 'dream' kit would be SEAS KingRO4Y Mk III Speaker Kit.

If you want to go the plans route... Troels has some cool Purify speakers. You could modify one of his plans to build something similar to the Radiant speakers.

And when you look at a kit that's going to be roughly $3,400 USD before the cabinet... it kinda makes the Fidelia and others a relative bargain. ;-)
 
Yeah, and you need to be careful... its a rabbit hole.
How far do you want to go?

Realistically, if I were going to DIY speakers, I'd design it myself and use Purifi drivers, maybe the RO4Y for bass if I went 3-way.

However, after thinking about this for a long time, pricing it out, etc - it made a lot more sense to buy some nice speakers instead. I got a nice deal on some LS60s + subs and forgot about building speakers. Now my DIY work is around building acoustic treatments for my office. :D
 
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Realistically, if I were going to DIY speakers, I'd design it myself and use Purifi drivers, maybe the RO4Y for bass if I went 3-way.

However, after thinking about this for a long time, pricing it out, etc - it made a lot more sense to buy some nice speakers instead. I got a nice deal on some LS60s + subs and forgot about building speakers. Now my DIY work is around building acoustic treatments for my office. :D
Well those Pure Audio Project speakers ship as a flat pack and you have to assemble them. Does that count as a DIY kit? :facepalm:

But sure. These days you can get some really good speakers that aren't going to cost you your first born.
If you go RO4Y there are a couple of options. Linkwitz uses them. And the SEAS KingRO4Y speakers are on my dream list.

Seriously though... price out taking a design like the Troels' Purifi speakers and then add two Purifi PRs. You're looking similar to the Radiants and I have to wonder if you're saving any money. (Good luck getting the baffle close...) The point of doing DIY is to challenge yourself. Part of the fun is building the speakers and then when your friends come over... constantly remind them that you built the speakers as you're pouring a very good bourbon or whiskey... ;)

On a side note... it would be cool if Audio First offered an option for the Baffle, Drivers and XO That would be cool. That should cut down on the cost of shipping to the US.
Of course he'd have to also send you the plans so you can build the cabinet. Also I'm assuming that the front baffle is not 3D printed but molded/stamped plastic or something like that. Or am I wrong?
 
I'm assuming that the front baffle is not 3D printed but molded/stamped plastic or something like that. Or am I wrong?
It looks like it could be 3D printed, but the finish is pretty smooth and finishing 3D prints to look like that is a total PITA, so my guess is they are doing a small run of molded parts, or it's machined.

If it is 3D printed I would be very interested in their post-processing routine.

Seriously though... price out taking a design like the Troels' Purifi speakers and then add two Purifi PRs. You're looking similar to the Radiants and I have to wonder if you're saving any money. (Good luck getting the baffle close...) The point of doing DIY is to challenge yourself.

Agree on the cost and challenge points. I didn't feel like I could justify $3K+ in parts plus the time and effort, just to end up with something that may or may not outperform a commercial speaker at the same price. And I don't have a great place for such a speaker, either.
 
How would these speakers work as nearfield monitors? It seems like the horizontal dispersion is a fraction wider than KH120 or KH150 but it’s tempting to build a pair for the desktop.
 
How would these speakers work as nearfield monitors? It seems like the horizontal dispersion is a fraction wider than KH120 or KH150 but it’s tempting to build a pair for the desktop.

Hi Andrew, I designed the Fidelia with a short listening distance in mind. The shorter-than-typical tweeter/woofer centre-to-centre distance and the low crossover point work well to trick our brain into hearing them more like a single acoustic point source. If I have to describe this in a subjective way (I know I have to be a bit careful when using this term here...), they sound more "coherent" compared to other typical 2-way designs crossing at 2xxx - 3xxx Hz at a close listening distance. Hope that help to answer your question.
 
How would these speakers work as nearfield monitors? It seems like the horizontal dispersion is a fraction wider than KH120 or KH150 but it’s tempting to build a pair for the desktop.

Should work great nearfield.
 

This looks to be an excellent speaker design. Similar to the Ascilab C5B although DIY construction.

Audio First are local to me so I am tempted to try and get a demo…

What shocks me the most about it:
Erin is doing all these measurements, comparisons and reviews to listen to such terrible music as in the video at minute 09:00 ?
 
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