Time for another DIY Speaker project

Will seek your help to do these measurements after they reach Mumbai.
In my case what i listen and what i measure usually don't correlate well. Someone had said this before - What you measure and what you listen are very different and is the greatest held secret in audio ;)-
 
The tuning by ear - was that done for port/box, crossover or both?
Purely by altering the Port length and damping. X-over was made as per the published specs and untouched.
In my case what i listen and what i measure usually don't correlate well. Someone had said this before - What you measure and what you listen are very different and is the greatest held secret in audio ;)-
I'm not too concerned but since you asked and since there may be other FMs who may also be interested, sought your help.
 
So, what was the the ID and length of the port you ended up with?
What was done for the damping?
Don't know how much ID (internal damping I guess) was used but the port length we ended up is 6" and there's no flare at the other end. There's scope for some experimentation I guess, which I'll do after getting them to Mumbai.
 
ID - I thought was inner diameter.

Btw, any images of the completed crossover to feast the eyes?
I was so engrossed in listening that I forgot to take the pics. The speakers are getting packed today and I'm busy with my official work till tomorrow evening. I'm free on Thursday and will try and click pics if they are not packed already. Else, this will happen only after they reach Mumbai.

No change to internal dimensions.
 
Yes, flared port it is. Could you elaborate on the challenges or rather lack of it!
A flared port is far less prone to wind noise but due to the flare, the overall length (with flare) of the port is longer.
i don't know from where to start my fine tune without my simulations and measurements.

Imo, only the most talented and experienced DIYers can tune by ear.
You cannot start with the ear. You have to start using measurements. Only the fine-tuning can be done by ear.
I built my first pair of loudspeakers using Philips parts in 1976 or maybe even a little before that. I didn't have measuring tools so built it on faith from a kit. The first pair had an 8065 woofer, 5060 Midrange and a 0210 tweeter. I built several other speakers using Philips and Bolton drivers before I settled on an array of 50mm EJ Jordan modules (Ted was still married to Dorreen at the time. She later went on to form Bandor) with a 10" Volt woofer for the bass in 1981.
Thanks @Hari Iyer they're anything but compact.
They are about the size of my first speakers.
In my case what i listen and what i measure usually don't correlate well. Someone had said this before - What you measure and what you listen are very different and is the greatest held secret in audio ;)-
Almost always. I found early on that the only thing measurements will tell you is if your design is seriously flawed. There is a young Asian reviewer on youtube called Thomas. He is in the process of introducing his own amplifier and speakers and he had a discussion with Harley from Pearl Acoustics about this. Do look it up.
 
A flared port is far less prone to wind noise but due to the flare, the overall length (with flare) of the port is longer.
Thanks so much for the explanation.
You cannot start with the ear. You have to start using measurements. Only the fine-tuning can be done by ear.
The speakers sounded terrific to me and an able replacement of the Aristas. But since the measurements have not been taken, I'm prepared to assume that the speakers are still WIP and do the measurements. It'll be interesting to see how they fare.
Ted was still married to Dorreen at the time. She later went on to form Bandor) with a 10" Volt woofer for the bass in 1981.
Pardon my ignorance but who are they? Tried looking up but nothing meaningful shows up.
There is a young Asian reviewer on youtube called Thomas. He is in the process of introducing his own amplifier and speakers and he had a discussion with Harley from Pearl Acoustics about this. Do look it up.
Got it. Hope this is the one:
 
Pardon my ignorance but who are they? Tried looking up but nothing meaningful shows up.
Ted (Edward) Jordan made a rather inefficient (I think they were 82db) full-range 2" (50mm) module in the 70s. By using them in arrays of 4 and adding a woofer for the bass you could make a pretty decent full range speaker using almost no crossover. The most famous of these 50mm "modules" was the JX53 (50mm version 3).


In the late 80s or early 90s Ted, teamed up with an up and coming german designer (he has designed the latest ) called Karl Heinz Fink and they formed a company called ALR Jordan. ALR made traditional 2, 3, 4, way loudspeakers such as the Faktor 2, Faktor 7, Note 2, etc.. (some random links below).

Ted was married to Dorren Bance who helped him build EJJordan designs. Dorreen later divorced Ted and started her own loudspeaker company called BanDor. Maybe she's not have divorced Ted, if like Dudley Harwood, he'd have named his company after his wife. Dudley, named HarBeth after his wife Elizabeth (ElizaBETH HARwood get it?).

I don't know if one can rely on Google for everything. I tend to rely more on what's left of my aged, senile memory.

Meanwhile, youtube suggested this video to me. I do agree with much of what is said here. Not all, but a lot of it.
 
A long-awaited update: I’ve been travelling for most part of the month and was hardly having time to compose and post the happenings on the speaker front. The speakers had finally landed in Mumbai, by and large intact but with cracks in the acrylic plate on which, the binding posts were mounted.

This is what the binding post mounting plates have been reduced to:
IMG-20220620-WA0012.jpg
A bigger shock awaited when I took home and sought to connect. The crossovers, which were packed separately, had their heavier inductors dislodged from the breadboard. It was a mistake on the part of the assembler not to use cable ties to fix the inductors to the boards:
IMG-20220620-WA0016.jpg
As I do not have any of my electrical or for that matter, even mechanical tools at Mumbai, I was looking for someone to help me in fixing these issues. I was in touch with FM @Hariiyer as used to exchange messages on the developments on the audit front. He generously offered to help me despite his domestic compulsions.

I put the speakers in my car and headed to his place. We took those heavy speakers to his 3rd floor residence. We left the cracked binding post plates as it is but mended the crossovers and affixed them onto the breadboard using cable ties. One side of the plastic spool of the inductors had to be cut to reach the inductor cable to be able to resolder it.
IMG-20220620-WA0011.jpg
Repairs done, we connected it to Hari’s DIY Tube Amp and played his favourite retro Hindi tracks.
IMG-20220620-WA0014.jpg
While they sounded very good with his DIY Open Baffle speakers, the Statements sounded shrill, which we attributed to unbroken in drivers. Less than ideal handling of the speakers could also to be blamed, I guess.

I took them back to my place and started to play them. They were opening up as I played them over a period of a couple of weeks, but I was disappointed with the bass response or rather lack of it. This was not the case when I auditioned them at Romit’s place. Nevertheless, I kept playing them for about two weeks or so.

In the meanwhile, I had to rush home to swap the car that I’m driving at Mumbai with the one I left behind at Hyderabad, which, my daughter was driving, as its AC went kaput and it couldn’t be fixed, apparently. I loaded the speakers in the back seat in unpacked condition, but the speakers arrived at Hyderabad safely.

I was also in touch with FM @hydrovac who was keen to audition them. I took some time off and visited his place. We hooked them up with the DD Pre-Power combo, the source being Marantz SACD player. While they were a fine set of speakers, the missing bass was a cause of concern.

I decided to modify the ports as per the original design and contacted Eight Audio but sadly, they were too busy to accommodate my request. In the meanwhile, I had ordered 4 Nos. 2” dia x 2½ long ports from Tanotis with an intention to make flared ports of the given specifications. They took a month or so but finally delivered:
IMG-20220620-WA0010.jpg
Waiting to go back and modify the speaker boxes.
 
If you haven't already, go after leaks first--that'd explain everything. Check all the mating surfaces (did driver frames get bent?). Partic the terminal plate. Get everything airtight first, then you'll know where you are. Here's a quick example screenie of a statement mini model with "normal" and higher loss--note that both of then stay <1Hz difference in tuning.

You don't need fancy custom gaskets--use what you have. You can use plastic bags and a hole punch just to get a layer between the wood and the other mating surfaces. Tape, silicone, whatever--just make the surfaces as flat as you can that gets a seal. Do a phone app RTA even--for before and after differences--doesn't need to be fancy/calibrated. While I'm on it, PE has a comparatively inexpensive phone mic if you're an Android person and want something calibrated.

If it's that much different from at Romit's, either it was in a corner there and now it's not, or something else is going on. The idea is to get the test--so even temporarily sealing the whole back of the terminal (screw heads and all) with (say removable painting) tape, etc. is the objective.

If the frames got sprung bad enough, you might be able to feel a voice coil rub when you push (gently) the drivers in and out. Doesn't sound like it, but I've had weird experiences, too. Always check the obvious stuff in case it works :)
 

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If you haven't already, go after leaks first--that'd explain everything. Check all the mating surfaces (did driver frames get bent?). Partic the terminal plate. Get everything airtight first, then you'll know where you are.
Hi @grindstone thanks for the tips. I had undertaken build of Tannoy Monitor Reds in Corner GRF cabinets and have experienced this. Moreover, since the boxes were made by a professional speaker maker, the leakage issues have been taken care off. And, the frames of the drivers are in perfect shape.
Do a phone app RTA even--for before and after differences--doesn't need to be fancy/ calibrated. While I'm on it, PE has a comparatively inexpensive phone mic if you're an Android person and want something calibrated.
Thanks again. Right now, the speakers are lying at Hyderabad for modifying the box to incorporate a 2" port, as per the published design.
If it's that much different from at Romit's, either it was in a corner there and now it's not, or something else is going on.
I think it's the choice of music at play. At Romit's place, we've played vocal-centric music predominantly. At my place, I was playing classic rock.

I'll post my impressions once I get the port modification done.
 
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