• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). Come here to have fun, be ready to be teased and not take online life too seriously. We now measure and review equipment for free! Click here for details.

DIYSG HTM-12v1 Speaker Review

johnp98

Active Member
Joined
Jan 29, 2021
Messages
112
Likes
166
If I'm being honest, it didn't sit well with me at first. I wanted a representative example of what is currently available. Unfortunately, I wasn't told what I had received until after I had tested it and sent Matt some preliminary results. That bothered me because I didn't test what I intended and thought I was testing.

That said, nope. Ain't no one compensating me anything for this.

Man I feel for you. That really sucks!
I was going to wait for the review to be up before donating to your cause. But yeah donation incoming right now, as this maturity is commendable. I hope it has not burnt future bridges with the DIY community in general.
 

mtg90

Member
Joined
May 24, 2021
Messages
20
Likes
70
Location
Illinois
I apologize I should have told Erin up front about the minor revision and sent a stock crossover as well perhaps to do a quick on axis test of both and the full measurements on whichever crossover looked more promising.

Here is the normalized difference in response between the crossover I sent Erin (flat line) and the Stock crossover, (For whatever reason REW is normalizing both to 3dBFS):
HTM-12 v2 stock vs revised normalized.png


I hope if this can be used in some way to apply a correction or small EQ to the NFS data for a more accurate representation of the stock crossover.
 
OP
hardisj

hardisj

Major Contributor
Reviewer
Joined
Jul 18, 2019
Messages
2,623
Likes
12,180
Location
North Alabama
Matt, there is no way to apply such a correction that I would feel confident of. Yes, I could export the data and apply a correction using some other software such as VCAD, but it would take it out of the Klippel environment. And even with that said, I'd still not be certain that a generic correction would be entirely accurate. Not to mention all compression testing and HD measurements would be rendered moot.

I would much rather re-test the real thing if possible. And I am willing to bet current owners would, too. If you don't have the parts on hand, I am hoping Erich can send me them.
 
OP
hardisj

hardisj

Major Contributor
Reviewer
Joined
Jul 18, 2019
Messages
2,623
Likes
12,180
Location
North Alabama
And I'll say this... I'm quite impressed by the v3 you did send. There are still some things that are odd (which you and I discussed) but I think it is a solid step up and if the v2 truly is better then that's great. I look forward to getting this information out there. Stupid Klipsch Heresy IV costs $3k/pair and is much worse than the v3 you sent. I've been looking for something to counter with when people say "so, what does better, then?". ;)
 

TimVG

Major Contributor
Forum Donor
Joined
Sep 16, 2019
Messages
1,010
Likes
1,918
I understand the market for passive loudspeakers. With speakers such as this however, and with DSP, power amps and even plate amps with integrated DSP being readily available at fair prices, why not simply go active and make a truly good loudspeaker. I can't imagine DIY folks being against active crossovers.
 
OP
hardisj

hardisj

Major Contributor
Reviewer
Joined
Jul 18, 2019
Messages
2,623
Likes
12,180
Location
North Alabama
I understand the market for passive loudspeakers. With speakers such as this however, and with DSP, power amps and even plate amps with integrated DSP being readily available at fair prices, why not simply go active and make a truly good loudspeaker. I can't imagine DIY folks being against active crossovers.


Last year I bought a miniDSP DRC-88A so I could specifically use it to help me build active designs. I also bought parts to make a cheap CNC. But that didn't pan out and I forgot about the miniDSP until yesterday afternoon when I was talking to someone about these speakers. My idea was that I could design the active network to get the crossover as good as it could be, then build it from passive parts (assuming it wasn't costly/complex).

That said, I might (might) try to toy around with some DSP things on the miniDSP with this speaker and see if I can come up with an active design that is pretty cool.
 

TimVG

Major Contributor
Forum Donor
Joined
Sep 16, 2019
Messages
1,010
Likes
1,918
Last year I bought a miniDSP DRC-88A so I could specifically use it to help me build active designs. I also bought parts to make a cheap CNC. But that didn't pan out and I forgot about the miniDSP until yesterday afternoon when I was talking to someone about these speakers. My idea was that I could design the active network to get the crossover as good as it could be, then build it from passive parts (assuming it wasn't costly/complex).

That said, I might (might) try to toy around with some DSP things on the miniDSP with this speaker and see if I can come up with an active design that is pretty cool.

That would be pretty cool. I'd just aim for proper time allignment as to get a proper forward lobe, put in an LR4 (acoustical) crossover I'm guessing somewhere around 1kHz (give or take), and a couple of broad filters to get a flat on-axis regression line, and then take out whatever resonances show up in the detailed measurements with some sharper filters if needed.
 

Cam Man

New Member
Joined
Jun 4, 2021
Messages
2
Likes
1
Greetings gents. I've stumbled onto the website and this thread. As a fairly early adopter of the HTM-12 ver 1 (Jan 2017), the tests and all your comments are very interesting. I am not a speaker designer or even an engineer, but have just enough training and experience to enhance my listening enjoyment. With much time spent in very fine screening rooms and such in my career, I have a subjective bias for the experience that speakers in large rooms renders. These tended to be dubbing stage in size and quality. For this reason, I find the characterization of this type of speaker as "Power Hi-fi" a good one. My room is large, and throw distance to MLP is about 15'.

Back in the day when I built these, I did a close mic look at the HTM-12v1 well away from boundaries using OmniMic, and found it reasonably smooth...more along the lines of what Matt provided at that time. Based on that, it is likely my HTM-12 components came from the early runs that Matt used. It would be far from a definitive look as provided here, but it was good enough to get some idea about what to expect, and significantly different from other well designed manufactured models I've done the same with.

Based on the availability of the results here, I have a question for the gallery regarding the ongoing discussion here of speaker EQ and room correction EQ. Given that we have test results showing not only axial response, but also sound power, it seems that the HTM-12v1 has similar horizontal on-axis and off-axis performance which would appear to lead to a power response that is similar in shape to axial response (just at a lower level). Would this not indicate that a room correction platform that is based on a mix of axial response and power response will also improve axial response, improving the room and axial response at the same time? Although the discussion here is specifically about the HTM-12v1, is the concept the same for others?
 
Last edited:

beaRA

Active Member
Joined
Apr 16, 2021
Messages
118
Likes
151
Well that is most unfortunate.
So we will have measurements to a "version 3" that never has nor will see the light of day o_O
I really hope that the changes in the crossover were subtle and truly only a few dB here or there as its very unfortunate that we wont get klippel measurements for the current and ongoing version.
Makes you wonder if we would have ever known about the crossover mod if it measured better than the v2 crossover.
 

mtg90

Member
Joined
May 24, 2021
Messages
20
Likes
70
Location
Illinois
I did not intend for any deception or malice.

My only intention was to provide Erin with what I planned to be the current version of the HTM-12 v2 crossover going forward. Expecting to make this very slight change to the crossover based on the differences I saw between Erin's HTM-12 v1 measurements and my own reviled by the more accurate NFS tests. I only wanted to provide people with what I hoped to be a better measuring/sounding speaker kit, so I did not want to send Erin an old version of the HTM-12 v2 crossover if all the future versions of the speaker shipping out were to get this minor update. It was my failure to let Erin know before hand that I was sending him an updated crossover. In the end the adjustments I made to that crossover I sent resulted in a small change to the response in the wrong direction and I'm sorry I wasted Erin's time testing it.

It was literally just a cap and resistor that had a small tweak to their value resulting in at most a +-1dB difference in response over a small portion of the range. This was not a HTM-12 v3, more like an HTM-12 v2.01.

I only expect very minor differences in performance with the original versions of the crossover and believe the minor differences in the drivers or crossover component tolerances and/or individual builds of the speaker may result in a greater variance in response then that small change I had made to the crossover.
 
OP
hardisj

hardisj

Major Contributor
Reviewer
Joined
Jul 18, 2019
Messages
2,623
Likes
12,180
Location
North Alabama
FWIW, this is the message I sent Matt earlier this week (before he mentioned the updated crossover). So, keep in mind this isn't actually the v2 (despite the title of the graphics). It does give you guys an indication of how the performance changed for the better from the v1 tested in this thread, though.

I would have to double check, but this might be the best controlled directivity I've measured so far. Look at how well the radiation pattern in red follows the +/-40 degree window.

------------------------------------------------------------------------


"Don't share because the review isn't done yet but I wanted to let you see the fruits of your labor...

cea2034-diysg-htm-12-v2-png.3139748



diysg-htm-12v2_360_horizontal_polar-png.3139749




Looks much, much better. And sounds that way, too. If you (we?) could figure out what is causing those resonances then you could clean up the midrange and really make this sucker shine. I think it is standing waves inside the enclosure. I can try to add a lot more stuffing inside if you'd like. Not sure when I'll get the chance but it's easy enough to try and just take a single on-axis response measurement to see if it helps."
 

Dj7675

Major Contributor
Forum Donor
Joined
Jan 12, 2019
Messages
1,253
Likes
1,455
FWIW, this is the message I sent Matt earlier this week (before he mentioned the updated crossover). So, keep in mind this isn't actually the v2 (despite the title of the graphics). It does give you guys an indication of how the performance changed for the better from the v1 tested in this thread, though.

I would have to double check, but this might be the best controlled directivity I've measured so far. Look at how well the radiation pattern in red follows the +/-40 degree window.

------------------------------------------------------------------------


"Don't share because the review isn't done yet but I wanted to let you see the fruits of your labor...

cea2034-diysg-htm-12-v2-png.3139748



diysg-htm-12v2_360_horizontal_polar-png.3139749




Looks much, much better. And sounds that way, too. If you (we?) could figure out what is causing those resonances then you could clean up the midrange and really make this sucker shine. I think it is standing waves inside the enclosure. I can try to add a lot more stuffing inside if you'd like. Not sure when I'll get the chance but it's easy enough to try and just take a single on-axis response measurement to see if it helps."
Very cool of you to take this on. Having access to these measurements will result in better speakers from DIYSG. Also, credit to them sending them in and working with what you find (warts and all in the case of the volts). The HTM12 does look very promising for sure. I would love to see you hook it up to your minidsp and bypass the crossover all together. Very interseting for sure.
 
OP
hardisj

hardisj

Major Contributor
Reviewer
Joined
Jul 18, 2019
Messages
2,623
Likes
12,180
Location
North Alabama
Also, credit to them sending them in

FWIW, there is a local fellow about 30 minutes from me who brought these over. He is loaning me the HTM and the 1099's to test. Found me on AVSforum and messaged me last week. He's a cool dude who is interested in seeing data.
 
Top Bottom