Dual tank reverb

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mediatechnology
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Re: Dual tank reverb

Post by mediatechnology »

Tubetec wrote: Mon Jun 23, 2025 3:14 pm Ive just struck a deal on a few of the Sennheiser MZA-14 P48's ,
Amazon has them for $489 US.
https://www.amazon.com/Sennheiser-00296 ... B003ZZTOFE

You must have gotten a really good deal.
Tubetec
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Re: Dual tank reverb

Post by Tubetec »

Boxed examples in immaculate condition appear on Ebay for around the 100 euros/$120.

Im all about a modular approach , it allows more flexibility than a self contained unit from a processing perspective ,
It also means the recovery transducer is remote from the mains transformer and their associated field ,

Im wondering how Mid/Side processing might fit into the equation ,
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mediatechnology
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Re: Dual tank reverb

Post by mediatechnology »

Tubetec wrote: Mon Jun 23, 2025 8:59 pm It also means the recovery transducer is remote from the mains transformer and their associated field ,
Any mains transformer.
Buy some mu-metal off eBay (or one of your many amazing sources LOL) and wrap a sleeve around the hum-bucking-wired receive coils.

I had a client once who asked me to solve a hum problem.
Turns out he didn't do his Due Diligence before he signed his lease and located his studio next to an MRI machine in the space next door.
To add insult to injury he also had to deal with the not only the MRI and it's power supply but a pad-sited utility distribution transformer, for the MRI, outside his back door.
Recording electric guitar required aiming the neck of the guitar in the null of the three or four high-flux fields.
Tubetec wrote: Mon Jun 23, 2025 8:59 pm Im wondering how Mid/Side processing might fit into the equation ,
It might fit well but a Width Control would be more user friendly and functional.
https://proaudiodesignforum.com/forum/p ... php?t=1266
I borrowed the above from the VAB-84. For SE I/O only a single 1246 and three 1240 are needed.
These could be replaced by op amps and 1% resistors if you feel like it.
The advantage over Ric Chinn and similar versions is that it uses a single gang pot.
May not mean much until someone goes the stepped switch approach which saves significant cost.
Tubetec
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Re: Dual tank reverb

Post by Tubetec »

I noted the Demeter Real-verb has a mu sheild in the vicinity of the pickup transducers ,
https://youtu.be/ump0Gu2B2Ao
Demeter-RVB-1-RRP-1-Real-Reverbulator-inside..jpg
DemeterRV-1.JPG
I know CRT osscilloscopes sometimes have a mu sheild , but I cant think of many other sources from recycling ,
I know cutting and bending it can damage the magnetic properties , a minimum bend radius sounds like a good idea ,
There is a few sellers of the foil tape on ebay . Presumably the tape will be wound onto a former not simply folded and put in an envelope .
Tubetec
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Joined: Sun Sep 08, 2024 7:08 pm

Re: Dual tank reverb

Post by Tubetec »

I was able to find three well used MZA-14's for around 50 euros each ,
They can be found used stateside on Ebay for reasonable money ,
Heres one up for auction in the next 2 days ,
https://www.ebay.ie/itm/116659869539

I was able to order a DM-1 clone off Ali , just to test the delivery dates are real and see what the quality is like , the 99 cent deal didnt materialise .
It should arrive early next week ,all going according to plan .
Tubetec
Posts: 349
Joined: Sun Sep 08, 2024 7:08 pm

Re: Dual tank reverb

Post by Tubetec »

I have an Amek BC3 which has a width control built into the stereo channels ,
It is a nice feature to be able to sweep from centered mono to panned L-R/R-L all on a single control . Definately something I want to try out with multiple springs .
Doing the whole opperation with a single gang pot , thats really neat .

Just realised the link I posted previously is for a MZA-14T .
Tubetec
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Joined: Sun Sep 08, 2024 7:08 pm

Re: Dual tank reverb

Post by Tubetec »

The MZA-14s arrived ,
They were labeled BBC News with a contact phone number ,
Condition is used ,but fully functional , there was a few case screws missing and one had a screw adrift inside the enclosure ,
all easy stuff to put right . The battery hatch cover was replaced on one with a home made plastic flap , but it works just as well as the original .
I tested them with my MKH416 P48 , they all pass signal with very low noise ,so safe to assume all is well. I also tested the MZA14 into balanced line input , lightening the load might improve THD to some degree on higher level sources ,

The DM1 clone arrived in , its like something that came in a lucky bag ,
I took a look inside , a single k170 fet , single ended input/output , its probably worth around 99 cents but not the ten euros i paid ,
https://www.aliexpress.com/item/1005008023936041.html
Came with a case that might be of use , other than that its junk , dont buy it .
Along with the order came a brass radiused fret press for 20 my buddy ordered , its very similar to an item StewMac sells for(correction) 290$ , quality is excellent , so not everything off Ali is a load of bollocks , but it is easy to get caught .
https://www.aliexpress.com/item/1005009012592536.html
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