Hotel room is booked and I’m excited. Been going to the Indiana/Ohio/Michigan events since 2009, but never been to Iowa in all these years. Looking forward to seeing some new faces! Bringing my brother as well to join in the fun.
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What is the Address and Time do I need to sign up or just come.
I will be attending again this year with a new pair of “mystery” high end 3 way towers that I am currently working on. Hope to have them ready to play in time. Unfinished cabinets, though.
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Location is linked earlier up in the thread. Oct. 16th and 17th, I’m guessing starting at 9am, but I’m not sure about that.
This will be my first time attending here. Does it start at 9am on Saturday? Is there anything going on for Friday evening? Trying to plan out my schedule. I’ll have at least one pair of speakers, Potentially a second if I can get them done in time.
Hey Rob! Folks typically start rolling in around 2-4 or so Friday afternoon to start setting up and getting some tunes going. Festivities will occur through Friday evening just jamming out to music, assembling speakers that need assembly, troubleshooting gear that needs troubleshooting, and having a couple beers (or maybe more than a couple) while chatting about tech and stuff. It’s a good time!
People will probably start filing in around 8-9 or so Saturday morning. I don’t know when they start testing as usually I’m late for the first couple, but I would guess no later than 9. Festivities will occur again Saturday evening once everyone had a chance to present their speakers for the event. I think we’re often done with the demos 5 PM that day, but it depends on how many speakers are presented. Last year a couple of us jammed out til…something past midnight, but it’s a bit hazy as to the specific time. We got very loud.
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I really hope I can attend again this year. Some job stuff might wreck that 
we’ll see. I don’t think I will have anything new to bring though. I could bring something previously demo’d if no one has any objections.
Hope you can make it, Craig! Just put a sticker on the back of one of yours and call it “Revised”.
I’m probably recycling last year’s failed project. Sounds quite a bit better now in my room, but we’ll see how it does in the big room.
Hello follow DIY brethren. Let’s get this party started. Arrangements are set at the usual venue in Ankeny, IA.
Below are the details. Most important rule: Be considerate of your DIY bros. Any questions, please contact JR, who will direct you to Mrs. JR, who will enforce this rule. Pro tip: don’t mess with Amanda.
IowaDIY 2026 — October 16–17, 2026
Friday, October 16 & Saturday, October 17, 2026
Best Western Premier — Ankeny, Iowa
Hotel
Best Western Premier - Ankeny
2502 SE Tones Drive
Ankeny, IA 50021
(515) 965-5678
We have a group room rate of $129/night + applicable taxes.
The hotel group block includes Queen/Queen and King rooms.
FYI - you can get better rates via AAA, AARP, etc. Explore all options.
Friday, October 16 — Informal Meet & Greet
People will typically start rolling in around 2–4 PM Friday afternoon. We will in the BW Meeting Room.
Friday is our informal Meet & Greet. There is no formal presentation schedule.
We’ll spend the afternoon and evening:
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Getting settled and setting up gear
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Assembling speakers
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Troubleshooting whatever needs troubleshooting
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Listening to music
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Checking out everyone’s projects
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Talking audio, technology and DIY, and whatever.
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Having a couple of beers…or maybe more than a couple
Friday night is also “run what you brung.”
Most of us will probably have more than one design or project with us, so Friday is a great opportunity to get some listening time on things that aren’t part of the formal Saturday event.
This is your time to manage. Just remember that everyone should get a chance, so please don’t bogart the time or space or you will feel the wrath of Mrs. JR.
Saturday, October 17 — The Formal Event
8:00 AM — Setup
9:00 AM — Show starts
Please plan on being there and ready to go by 8:00 AM for setup. The show will start promptly at 9:00 AM.
The exact ending time will depend on how many projects are presented, but we’re generally expecting the formal portion to run into the afternoon, potentially until around 5 PM.
The 12-15 Minute Presentation Format
We’re keeping the formal presentation slots tight:
4-5 minutes — House track
4-5 minutes — Personal demo
4-5 minutes — Setup/teardown
12-15 minutes total per time slot
That’s tight, and we’re going to be right up against the clock.
Please save extended Q&A and technical discussions for the informal time or take them into the lobby.
Please give presenters your full attention
During the formal presentations:
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No chatting, crunching, slurping, bitching, etc.
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No jingling keys, coins, etc. in your pockets. That’s just weird.
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No distracting behavior.
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Please pay attention while someone is presenting.
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If you’re asked to quiet down, please respect it, or go home.
Everyone deserves the same opportunity to present their work and have people actually listen to it.
It’s simply a matter of respect for your fellow DIYers.
Lunch
We’ll take approximately one hour for lunch. We usually do pizza lunch, compliments of MAC.
Details on exactly what we’re doing for lunch are TBD.
Saturday Evening — Run What You Brung
Once everyone has had a chance to present their projects, we’ll return to the informal “run what you brung” format.
This is the time to pull out the other projects you brought, listen to other people’s gear, experiment, compare notes, and generally have fun.
There is no formal schedule for Saturday evening.
And yes, this is an alcohol-friendly event. 
Important Ground Rules
Most importantly: HAVE FUN.
There are no feedback cards and no competition, and that’s intentional.
We’re absolutely encouraged to talk about what we’re hearing, ask questions and have open conversations about the projects. However, unsolicited feedback isn’t always welcome.
If someone wants your opinion on their speaker, design, measurements, crossover, sound, etc., they’ll ask. So please ask before offering criticism or feedback.
The formal presentations are also not the time for extended technical debates. Save those conversations for the informal sessions or the lobby.
The whole point of the weekend is to bring people together, listen to some interesting stuff, learn from each other, and have a good time doing it.
IowaDIY 2026 at a Glance
Friday, October 16
2–4 PM onward: Informal Meet & Greet
Evening: Run What You Brung, music, setup, conversation & hanging out
Saturday, October 17
8:00 AM: Setup
9:00 AM: Formal event begins
~5:00 PM: Formal event expected to conclude, depending on the number of presentations
Evening: Run What You Brung & informal listening
Location: Best Western Premier — Ankeny
Hotel: (515) 965-5678
Group room rate: $129/night + applicable taxes
Hotel booking: Best Western Group Reservation
Looking forward to seeing y’all in October!
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I guess you guys will probably see my ugly mug this year again. What I’m bringing to present TBD. I’ll come up with something.
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We’ll prepare accordingly
Now that we’re getting close to that time, I thought I would go ahead and post the measurement results I obtained for the amp we’ve been using at DIY Iowa for most of the past dozen years or so. This is the Samson SX2400, a pro audio amp that I purchased when new ones were being closed out. I got the last one from an online retailer at about half price, which if I recall correctly was about $250 - (return on investment has been very high for that purchase).
Let’s start with the spec sheet, then see if the actual measurements line up.
The quick summary: Plenty of power, extended frequency response, “meh” distortion and noise, but not terrible. It would take 26A to get full rated power at 4 ohms out of a 115V socket, so we should probably expect a little less…
Lets start out with the ASR-type “dashboard” measurements (1 kH signal at 5W output into 4 ohms) with the gain knobs at max (other settings resulted in more channel imbalance).
The distortion and noise floor starts around -80 dB (0.01% of signal) but there are a lot of different frequencies around that level, so the cumulative effect is 0.036% THD+N for the worse of the two channels (still within spec) - or a SINAD of just over 70 dB. Gain is quite high at almost 36 dB (spec is 34 dB).
Next, let’s look at frequency response.
Response is smooth and reasonably extended. We’re down about 0.25 dB at 20Hz and 0.5 dB at 20 kHz - better than spec at the low end. -3dB points are 4 Hz and 50 kHz vs. the spec sheets 5 Hz and 60 kHz claim. It’s possible my setup is contributing some to HF rolloff. Overall this is very solid performance and there is no measurable variance when switching between 4 and 8 ohm loads.
Of course, we all want to see the power measurements as this is what these amps are known for. Starting out with a 1 kHz signal…
First, there is a step up in distortion around 100-150W. When running the power sweeps, this corresponds to a relay switching on an attenuator in the Quantasylum audio analyzer. So, don’t read too much into that from an amplifier performance perspective. Onset of clipping appears to be about 400W into 8 ohms and 600W into 4 ohms. This doesn’t quite match the spec of 500W and 750W respectively - but remember that the max current draw at rated power is 26A. I’m running on a 20A circuit, the next model down SX1800 is rated at 400W into 8 ohms and 600W into 4 ohms with a max current draw of 19.5A - so maybe this makes sense. When I run into current limitations, I like to try testing a single channel. Here is the result of that.
Now the clipping points are closer to 450W into 8 ohms and 700W into 4 ohms. If one looks at where the curves cross the 0.1% distortion line, that is right around 500W and 720W respectively. So it appears that the Samson can deliver its rated power, but probably more like 400W into 8 ohms and 600W into 4 ohms at the hotel due to mains power limitations.
Next, we’ll look at other frequencies.
The SX2400 put out about 550W into 4 ohms at 30 Hz before clipping, which is pretty impressive. There was an extra 5-10 dB of distortion at 5 kHz and above, which still keeps us in a reasonable range and better than all but a few class D amps. The multitone test tells a similar story. At lower frequencies, the distortion/noise floor is about 96 dB down (16 bits - redbook CD resolution) with a few specific power supply noise peaks sticking above that. At higher frequencies, that drops to closer to 14 bits - still within the realm of good enough.
All-in-all the measurements suggest an amplifier that is relatively well behaved with a lot of power and bass capabilities. Overall fidelity is mostly competitive with typical home 2 channel setups, but not by any means exceptional.
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That’s good stuff, thanks for doing it.
I’m curious about your load jig. I’ll have to talk with you in Oct to glean some info.
If I were looking for a load I would troll the offerings of my local hardware store:
240v 4500w put that info into your favorite online calculator:https://www.digikey.com/en/resources/conversion-calculators/conversion-calculator-ohms
12.8ohm 4500w resistor 
Then you might find something in the 8 ohm(ish) range.
7.2 ohm 2000w:
video:DIY Audio Dummy load out of Water Heater Element? | Audio Science Review (ASR) Forum (not mine)
some people put them in sand or oil to disapate the heat just dont seal it and make a presure cooker.
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I really should post details about the high power load setup on my web page. I might have been guilty of over thinking some aspects, but there were a lot of things to consider…
There’s a really long thread about the Samson amp testing here that would give a lot of insite.
Long story short:
- I couldn’t test the Samson amp running the output through the QA451 load.
- In order to get a suitable output back to the QA403 analyzer, I had to use a voltage divider to get the required attenuation (and pick resistors that didn’t mess up distortion measurements).
- I had to change some settings to accurately reflect gain for a balanced amp.
- Once everything was sorted out, testing went as hoped.
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Guys - I obviously wasn’t paying attention the last few years, but how are we handling active projects? Is there a S/PDIF out on the rig I could feed into a DAC?
Tom, I typically get everything, including the house track and my track. You would need a multichannel Dac, unless you have a 2 channel system that’s fixing the wiggles.
I get the source (usually my laptop or phone), dsp + dac and multi channel amps and all the wiring that goes with it. You might be able to get the line level from the cd player or laptop source, but getting the full chain pre configured is faster and no need for troubleshooting.
I do have line level (RCA) inputs on the chap DSP box I’m currently using. But I was also planning on bringing a DAC that has volume control, just in case that’s easier. I had thought JR’s Oppo only had XLR outs.