Ela-M 251 Body from Aliexpress

[garp]

I can't say that i have no clou . I choosed the M23 series mainly because of the inflating prices of the antique amphenol tuchel 7 pins (available at Binder but badly distributed in Europe). And now i have problems finding Binder M23 i need for future projects (

 

[egroys]

175V is perfectly, that should deliver about (x 1.41) 245V DC, not rippled. Theoretically you can use every transformer above 120V AC secondary for the plate Voltage. You have more than enough Voltage after the D1-D4 diode bridge for the ripple the B+Plate down to 120 V DC, what is needed as Plate Voltage for the Mic. Might be possible that you want to decrease the R1 and R2 75K Ohm Dropresistors to 50k Ohm used for 175V instead of a 200V AC secondary output Transformer. But not really necessary. There is B+ R4 trimmer with 250k is for adjusting properly the 120V DC. The secondary 9V AC is ideal for generating the LM317 regulated Tube Heater/Filment Voltage down to 6.3V DC. If Poctops included "L" PSU - PCB is too big / high or to broad for the Retro Case, mount it with two bottom mounted 45 degree bent metal angles, diagonal, no disadvantage.

Have you (or anyone) used the Retro with Poctops L PCB? If so, can you send any photos of how you go it to fit? With the caps sticking out, it's feeling a bit sketchy and I am curious what the best way to make it work is. Please and thank you!!

 

[HerbertR]

Have you (or anyone) used the Retro with Poctops L PCB? If so, can you send any photos of how you go it to fit? With the caps sticking out, it's feeling a bit sketchy and I am curious what the best way to make it work is. Please and thank you!!

Hi, I used not the Retro II case/PSU with 251 PCBs. If the size of the Retro is the same as my Retro I case as in the picture, it might be a challenge to fit it. The L-shaped Poctop PCB is about 100mm x 140mm with 100mm x 40mm "Transformer cutout". This means that if the PCB was used rotated 90°, it would fit in the Retro II case. But then there would be too little space left to mount the power transformer even if it was also rotated 90° because the TX Block measures 50mm x 50mm incl Windings and is 40mm high, with the TX bracket for the moutings screws it measures a total length of 80mm. The Retro II case is much taller at 90mm and so you could possibly mount the TX on the side of the cover case. But then you might get the small chance of transformer interference. Regards

 

[egroys]

Hi, I used not the Retro II case/PSU with 251 PCBs. If the size of the Retro is the same as my Retro I case as in the picture, it might be a challenge to fit it. The L-shaped Poctop PCB is about 100mm x 140mm with 100mm x 40mm "Transformer cutout". This means that if the PCB was used rotated 90°, it would fit in the Retro II case. But then there would be too little space left to mount the power transformer even if it was also rotated 90° because the TX Block measures 50mm x 50mm incl Windings and is 40mm high, with the TX bracket for the moutings screws it measures a total length of 80mm. The Retro II case is much taller at 90mm and so you could possibly mount the TX on the side of the cover case. But then you might get the small chance of transformer interference. Regards

Thank you, that's good to know. I'll see if I can pull it off, otherwise I will have to get a TPS100!

What mic are you using the Retro II for?

 

[HerbertR]

Thank you, that's good to know. I'll see if I can pull it off, otherwise I will have to get a TPS100!

What mic are you using the Retro II for?

It's a Retro I case and I use it with Oliver Archuts C12 "self cathode biased" version circuit, Siemens Halske ECC801S, 3U C12 TX and an AKG C12VR Nylon capsule. I have a lot of unused components lying around. The build was a kind of "Restl' verwerten'" we would say in Austria. The nice looking mic housing is from Ali, but feels a little bit cheap, the green Tube is made from Alu and therefore feels slightly hollow.
But sound is pretty nice, well-behaved, clean, transparent and "right" like the source in real in front of the mic, like you would expect from a CK12 nylon AGK capsule in C414 with a homeopathic dose of dope. And not like a brass CK12 from all the well-known boutique manufacturers. But that's a bit off topic now...

 

[Ralph Welch]

Hi, I used not the Retro II case/PSU with 251 PCBs. If the size of the Retro is the same as my Retro I case as in the picture, it might be a challenge to fit it. The L-shaped Poctop PCB is about 100mm x 140mm with 100mm x 40mm "Transformer cutout". This means that if the PCB was used rotated 90°, it would fit in the Retro II case. But then there would be too little space left to mount the power transformer even if it was also rotated 90° because the TX Block measures 50mm x 50mm incl Windings and is 40mm high, with the TX bracket for the moutings screws it measures a total length of 80mm. The Retro II case is much taller at 90mm and so you could possibly mount the TX on the side of the cover case. But then you might get the small chance of transformer interference. Regards

Do you have a link for that case ?

 

[HerbertR]

Do you have a link for that case ?

As I said, the quality doesn't feel that great... the tube is made of 3mm thick aluminum, but the green powder coating is surprisingly high quality. A classic housing, as you would expect from better Chinese microphones. But not comparable with the HQ China Elam 251 bodies.
€39.99 | Kondensator rohr Mikrofon körper DIY Mikrofon Zubehör C12 Mikrofon Ersatz-grün
https://a.aliexpress.com/_Ex908mp

 

[Ralph Welch]

Nice ,but I can't seem to find the power supply case you are using

 

[egroys]

https://www.thomannmusic.com/the_t.bone_psu_retro_tube_ii.htm This is the smaller, 'retro' and the more appropritate fit for the 251 is https://www.thomannmusic.com/the_tbone_psu_sct_2000.htm

 

[egroys]

Hmm I’m also noticing that the Retro II transformer is 175v, not 200 as pictured above. Is this going to be a problem?

 

[HerbertR]

Hmm I’m also noticing that the Retro II transformer is 175v, not 200 as pictured above. Is this going to be a problem?

Absolutely not! 175V is perfectly adequate or even better as you theoretically have 35V less rectified voltage to drop across the drop resistors R1, R2 (and potentiometer R3). Perhaps it is necessary to lower/replace R1 and R2 75K ohms to about 56K resistors or so ...that you can play with R3 250K potentiometer in the 120VDC B+ range. That's all...

 

[egroys]

Absolutely not! 175V is perfectly adequate or even better as you theoretically have 35V less rectified voltage to drop across the drop resistors R1, R2 (and potentiometer R3). Perhaps it is necessary to lower/replace R1 and R2 75K ohms to about 56K resistors or so ...that you can play with R3 250K potentiometer in the 120VDC B+ range. That's all...

Brilliant! Thank you very much for this

 

[magnusp71]

I have been thinking about a rotary switch also.
For the time being I did it 'the simple way', a 3-position toggle switch...

This is great Ruud. Where did you find the body with the toggle switch? Does it work with Dannys circuit? Also, where did you find the shock Mount in same colour as the mic? Thanks

 

[paulcheeba]

I used the Chinese 251 and the Retro 2. Followed Herbert’s great advice and used top components like Beesneez BCK12. And it sounds better than most clones.

 

[egroys]

I used the Chinese 251 and the Retro 2. Followed Herbert’s great advice and used top components like Beesneez BCK12. And it sounds better than most clones.

Did you change the resistors in the Retro 2 and rearrange the inside to fit Dany's PSU board? I think I just sorted a way to do it. Will post photos upon success but would love to see how you did it for inspiration. Thank you in advance!!

 

[egroys]

Spray paint Satin black for bike exhaust, masking tape bake in the oven et voilà !

Hi! What do you mean 'for bike exhaust'? Like a high heat spray paint?

Thank you!

 

[garp]

exactly !

 

[AboveAndBelow]

New sound clip with some changes. Out went the Beesneez Capsule and in went OPR. The cathode resistor is now 2.7k(ish) with 20uf cap. Big difference to me. LOVING OPR's lovely bottom, perfect top, and balanced detailed mids. No eq or compression. Tim.
Old Sample
https://www.dropbox.com/scl/fi/nhvv...st-2.wav?rlkey=9vn830o2j3qgj4be3qcxeln31&dl=0
New sample
https://www.dropbox.com/scl/fi/hfrv...hode.wav?rlkey=18c7ndfjyaj5l1g9epuyvm5tc&dl=0

Hello the first sample is not working anymore, How would you compare the beesneez and the OPR ? i'm having a hard time deciding on one or the other.

 

[geekmacdaddy]

Hello the first sample is not working anymore, How would you compare the beesneez and the OPR ? i'm having a hard time deciding on one or the other.

Hi,
Sorry about that link. I would say the OPR has a beautiful smoky vintage bottom that the Beezneez does not, and the beezneez is a bit "crispier" on top...a bit more modern? Both sound great. The OPR in my 251 sounds ridiculous. My favorite mic.

 

[magnusp71]

New sound clip with some changes. Out went the Beesneez Capsule and in went OPR. The cathode resistor is now 2.7k(ish) with 20uf cap. Big difference to me. LOVING OPR's lovely bottom, perfect top, and balanced detailed mids. No eq or compression. Tim.
Old Sample
https://www.dropbox.com/scl/fi/nhvv...st-2.wav?rlkey=9vn830o2j3qgj4be3qcxeln31&dl=0
New sample
https://www.dropbox.com/scl/fi/hfrv...hode.wav?rlkey=18c7ndfjyaj5l1g9epuyvm5tc&dl=0

Nice! Could you possibly share all the resistor and cap values you ended up using?