[gregeagle]

hey guys...Need some help...
want to build the MASM6 (Bellsing 5+RAB 32063)..... which Zobels to use.....do i use the Zobel from BS6 (22uf, 25ohm) for the BS5 aswell....because i cant calculate the Zobel for BS5....do I Need zobel for RAB???

Thanks in advance!

 

[musmecca]

I was being provocative on purpose you have not angered anyone A truly "flat" response curve would not be neutral if you put it in your ear. The natural resonances which appear in your concha and ear canal can´t take effect if your ear is occluded.

I pretty much agree the diffused field curve with an enhanced bass which rises from 200-100hz is the most neutral for the middled summ of listeners. This curve will look kinda like Harman curve however there are quite a few problems with targed curves like dhruv said. It is really coarse... Look at what the range is of those treble and bass adjustmends.
For the young ear for example, which is hears higher frequencys better, more bass is preffered. For older Folks that might not be true.


Here is maybe a better scaled graph of the harman curve.

I know you were being provocative! And I was thinking "oh crap, we are now going to have a week long harmon debate and no one will send me a build until it's over"! LOL ...its all good. I hear you and know where you are coming from. On that note, what may shed some light on my sonic perception and highlight something that has NOT been discussed in this forum is a person's actual audiology report and personal response. I have attached mine from 2 months ago. If someone was going to make a truly custom IEM, how could this data be incorporated into a build? I have said most builds sound midrange sensitive/harsh and lack bass...kinda the inverse of this report. Compensation perhaps? LMK if you have thoughts...

 

[Farquarl]

I know you were being provocative! And I was thinking "oh crap, we are now going to have a week long harmon debate and no one will send me a build until it's over"! LOL ...its all good. I hear you and know where you are coming from. On that note, what may shed some light on my sonic perception and highlight something that has NOT been discussed in this forum is a person's actual audiology report and personal response. I have attached mine from 2 months ago. If someone was going to make a truly custom IEM, how could this data be incorporated into a build? I have said most builds sound midrange sensitive/harsh and lack bass...kinda the inverse of this report. Compensation perhaps? LMK if you have thoughts...

That is a matter i wanted to discuss as well. To make a truly flat IEM for you you hve to adjust for your own hearing. I asked my sister which is an audiometrist, and she replied that you likely have a hardness of hearing in the mids and highs. Which acutally makes me wonder why most builds sound bright and harsh for you.

Edit:
I replied too fast! She said that this "small, little" hearing hardness can cause exactly what you described. Apparently humans have two borders/limits in hearing. One is the level at which we can hear a sound which in someone with perfect ears would be something around 0dB (which we can see in your diagramm and most frequencys) the other level is the discomfort level at which the sound becomes uncomfortable to listen to. This level doesn´t shift! So in the highs and mid you basically have a small window of enjoyable soundlevel and thats why many builds sound harsh to you.

 

[dhruvmeena96]

Dhruv, I currenly have on hand twfk, Ed 30761 and 29689, Gv32830, Sr6438, CI22955, Fed30048, Rab32257, Hodvtec 31618, WBFK 30019, and only the sonion 33aj007...used up my other sonion products including my 3800's. I look forward to your thoughts...sounds like the 12BD fun version is what I'm after...I do have plenty of room in my shells and am pretty good at soldering.

HODVTEC (internal series) L-pad 4.7obm series parallel yellow
ED29689 - green damper - 22ohm series

HODVTEC tube as long as you can fit
ED29689 10mm with green damper at 8mm

The most simple Bass shelf + diffuse feild iem

If you wanna do complex, that can be done too




HODVTEC as above

Sonion 33AJ007(internal series)
10uF 47ohm RC high pass
Red damoer at 10mm
14mm tube
Adjust electrical connection to adjust phase
Technically reverse phase.

ED29689 CT
2.2uF High pass
14mm tube
Green damper at 10mm
Again reverse phase or just check phase in FR graph

WBFK as per taste


Why did I write check electrical phase


Because in certain connection
The 33AJ will dip at 200Hz which is regular in phase with HODVTEC electrically

And uppermid will cancel on 29689 if same phase HODVTEC

As crossover shift phases

So do check, that will give you better idea as how cross behave

 

[Bassiklee]

While I agree that crossovers induce phase shift, when you "swap the wires", you are flipping the polarity, not the phase. Phase has a time and frequency component. Polarity does not. I know it's essentially semantics, but I like to be correct in matters like this.

 

[shdh]

agree that crossovers induce phase shift

Doesn't phase shift only occur in crossovers that are greater than first order?

So theoretically if you only used 1st order crossover networks, could you avoid phase issues?

 

[musmecca]

HODVTEC (internal series) L-pad 4.7obm series parallel yellow
ED29689 - green damper - 22ohm series

HODVTEC tube as long as you can fit
ED29689 10mm with green damper at 8mm

The most simple Bass shelf + diffuse feild iem

If you wanna do complex, that can be done too




HODVTEC as above

Sonion 33AJ007(internal series)
10uF 47ohm RC high pass
Red damoer at 10mm
14mm tube
Adjust electrical connection to adjust phase
Technically reverse phase.

ED29689 CT
2.2uF High pass
14mm tube
Green damper at 10mm
Again reverse phase or just check phase in FR graph

WBFK as per taste


Why did I write check electrical phase


Because in certain connection
The 33AJ will dip at 200Hz which is regular in phase with HODVTEC electrically

And uppermid will cancel on 29689 if same phase HODVTEC

As crossover shift phases

So do check, that will give you better idea as how cross behave

Thank you sir! I will diagram these out and post them before I build. One last thing, what tube diameters and which are shared in the second version?

 

[Bassiklee]

Doesn't phase shift only occur in crossovers that are greater than first order?

So theoretically if you only used 1st order crossover networks, could you avoid phase issues?

That is incorrect. Every "order" introduces phase shift

 

[shdh]

That is incorrect. Every "order" introduces phase shift

Ah, I see. I was curious because I read this off Wikipedia:
"First-order filters are considered by many audiophiles to be ideal for crossovers. This is because this filter type is 'transient perfect', meaning it passes both amplitude and phase unchanged across the range of interest. "
https://en.wikipedia.org/wiki/Audio_crossover#First_order

 

[Bassiklee]

It varies. At the corner frequency, a first order filter is generally thought of as producing a 45 degree phase shift. That shift gets greater out of the passband, and lesser in the passband.

 

[tedbender84]

HODVTEC (internal series) L-pad 4.7obm series parallel yellow
ED29689 - green damper - 22ohm series

HODVTEC tube as long as you can fit
ED29689 10mm with green damper at 8mm

The most simple Bass shelf + diffuse feild iem

If you wanna do complex, that can be done too




HODVTEC as above

Sonion 33AJ007(internal series)
10uF 47ohm RC high pass
Red damoer at 10mm
14mm tube
Adjust electrical connection to adjust phase
Technically reverse phase.

ED29689 CT
2.2uF High pass
14mm tube
Green damper at 10mm
Again reverse phase or just check phase in FR graph

WBFK as per taste


Why did I write check electrical phase


Because in certain connection
The 33AJ will dip at 200Hz which is regular in phase with HODVTEC electrically

And uppermid will cancel on 29689 if same phase HODVTEC

As crossover shift phases

So do check, that will give you better idea as how cross behave

I have few questions - when you calculating L-pad which impedance do you use, DC or related to specific frequencies from data sheet?
I want to find a crossover frequency point between 38Dj and 38AM, for me it seems to be a same like you mentioned above for HODVTEC and 33AJ. Calculator says 10uF and 47ohm will give 3db slope at 338hZ.

 

[dhruvmeena96]

I have few questions - when you calculating L-pad which impedance do you use, DC or related to specific frequencies from data sheet?
I want to find a crossover frequency point between 38Dj and 38AM, for me it seems to be a same like you mentioned above for HODVTEC and 33AJ. Calculator says 10uF and 47ohm will give 3db slope at 338hZ.

DC

 

[Farquarl]

I have few questions - when you calculating L-pad which impedance do you use, DC or related to specific frequencies from data sheet?
I want to find a crossover frequency point between 38Dj and 38AM, for me it seems to be a same like you mentioned above for HODVTEC and 33AJ. Calculator says 10uF and 47ohm will give 3db slope at 338hZ.

Impedance is always frequency related and you should use the impedance at the crossover point to be most accurate. Not the DC resistance.

 

[tedbender84]

Impedance is always frequency related and you should use the impedance at the crossover point to be most accurate. Not the DC resistance.

For example 33aj has dc impedance 12ohm(believe parallel connected?) with 47ohm resistor parallel connected to driver resistance will give to us about 10ohm total circuit resistance. Calculating rc filter with 10ohm and 10uf will give us cut off frequency - 1500hz -3db(roughly)?
Or I should not add driver resistance to total RC filter, in this case hi pass will be 338hz -3db?.
Sorry for so many questions, but after I finish reading 776 pages - I have porridge in my head

 

[Farquarl]

For example 33aj has dc impedance 12ohm(believe parallel connected?) with 47ohm resistor parallel connected to driver resistance will give to us about 10ohm total circuit resistance. Calculating rc filter with 10ohm and 10uf will give us cut off frequency - 1500hz -3db(roughly)?
Or I should not add driver resistance to total RC filter, in this case hi pass will be 338hz -3db?.
Sorry for so many questions, but after I finish reading 776 pages - I have porridge in my head

You should use the stated impedance in the datasheet at the crossover point. The Drivers DC resistance does not matter as you are feeding your drivers AC. Impedance is frequency dependend resistance. A normal resistor has no impedance change (in the frequencys we find important) to care about.

Take your pick