— Forum Scope —

— Match —

— Forum Options —

Min search length: 3 characters / Max search length: 84 characters

Lost password?
Inline Devices for 2018
Jon O'Neil
Kill Devil Hills, NC
23 Posts
January 30, 2018 - 5:04 PM

Some of these changes were held over from 2017, as I just couldn’t quite get the time to bring them to market! Some are ready to go now, some will be soon, and some still on the drawing board will have significant revisions from the 2017 planned updates:

Coming for inline devices in 2018:

Already released:

– First, the VPD highpass (low cut) filter is available now in the selection menu. There are several versions, covering both microphone and line as well as balanced and unbalanced applications.

– Next, there are some new options in the MPD menu for 3.5mm miniplug to male XLR attenuators, both mono and stereo. Like other unbalanced to balanced MPDs, the stereo version is impedance-balanced to provide a balun function.

Coming soon:

– The long-delayed VPD midrange passive notch filter.

– An 5V-12V converter cable that enables use of 5V USB battery packs with the original IPA version will be made available–it’s already been tested and is just waiting for a PCB order for a final prototype. This function, which will be internal to the upcoming IPA version, will thus be extended to earlier versions as well.

On the drawing board for the year:

– The 2017 planned but unreleased IPA update has been expanded extra features: the 2018 power circuit revision not only reduces voltage drop for phantom powering, it also has an internal converter circuit so that the IPA can run on 5V external batteries, and has a charge regulation circuit so an internal 3.7V Li-ion battery pack will be options instead of the standard A23 battery provision. Even more exciting, the IPA can now support one, two, or four channels, with the output connector being XLR-3-M (mono or stereo) or XLR-5-M (stereo or four-channel)! Four-channel gain will be set with a hex switch, which yields two fully selectable gain levels per channel. Mono versions will use a six-position switch, and the stereo version will continue to use a three-position switch. All new versions of IPA will now use the extended case (most early ones did already, due to connector requirements).

Jon O'Neil
Kill Devil Hills, NC
23 Posts
February 9, 2018 - 5:51 PM

The MPD attenuators now have an option for right-angle connectors in the menu. That includes a right-angle XLR adaptor, which may be ordered as an attenuator, polarity inverter, or simply as a pass-through.


Jon O'Neil
Kill Devil Hills, NC
23 Posts
March 11, 2019 - 2:59 PM

Better late than never! The updated IPA version 2 will release in June, with the following upgraded features:

– one to four channels
– improved gain control: seven gain settings for one or two channel versions; three gain settings for four channel versions (with three-position switch rather than hex switch mentioned previously)
– regulated 6 to 16V supply to microphones from any power source (except A23, which is max 10V)
– option for internal rechargeable battery–3.7V Li-ion
– option for A23 or A544 battery holder
– external 5-15V supply
– improved performance with low-voltage (12-24V) phantom power supplies
– improved efficiency for optional polarization circuit
– optional input attenuation for “two-wire” microphones as a gain setting
– XLR-3-M, XLR-5-M, or RJ45 (four-channel impedance balanced output without internal battery) output options
– extended case only; auxiliary minijack input or output no longer available due to space constraints.

The 5V-12V converter cable is also available for order on June 1.

Jon O'Neil
Kill Devil Hills, NC
23 Posts
June 4, 2019 - 11:32 AM

And it’s finally out! Almost two years in the making, IPA version 2!!!


With the advent of four channels, there are a number of new output cable options, including four channel XLR-5 and XLR-10 fanouts to XLR-3, plus an XLR-5 to XLR-10 extension. The XLR-10 extension cable allows four-channel impedance-balanced interconnection from the IPA to the microphone amplifier input, while minimizing cable bulk with a multicore cable not much thicker than a standard microphone cable.


Launching later in June, a product positioned in between the PFA and IPA: naturally, the IFA! The IFA has the PFA’s circuitry in the old short IPA case. This is offered mainly for DI and dynamic mic applications, but may also be preferred for some active solutions, such as Schoeps KCY, such that the stereo Y cable can be on the output of the IFA (and thus nice durable XLR cables) rather than the more fragile lavalier cable a stereo PFA has to use. The IFA is phantom power only (no internal batteries or external DC jack). The IFA can have the +60V polarization circuit required for actives, which runs on any supply of 7.5V or more. The IFA does not have gain options–other than fixed gain for mono versions–but this is only suggested for the dynamic mic input.

In case you were wondering about my nomenclature:

PFA = Plug-in Fantom Adaptor (because the first version was only for PIP mics, way back in 2007!)
IFA = Inline Fantom Adaptor
IPA = Inline Powered Amplifier

Also on the Inline Devices range, the midrange notch filter option for the VPD is finally available, although in finishing that I sketched a three-band passive EQ circuit that incorporates the midrange notch plus LF cuts and a HF shelf. That will take a few more months to develop, but it could be worth the wait!


Jon O'Neil
Kill Devil Hills, NC
23 Posts
June 24, 2019 - 1:40 PM

The IFA is now available here:


Which adaptor to select? First, confirm your input:

PFA: low-voltage, “active” remote, or instrument “DI”; mono or stereo
IFA: low-voltage, “active” remote, plus dynamic and 12V T-power microphones, or instrument “DI”; mono to four channel
IPA: low-voltage, “active” remote, plus dynamic and 12V T-power microphones; mono to four channel

And then your desired format:

PFA: phantom-powered cable
IFA: phantom-powered adaptor
IPA: phantom power, internal primary or rechargeable battery, or external DC source; with gain control option.

Jon O'Neil
Kill Devil Hills, NC
23 Posts
August 23, 2019 - 8:37 AM

A quick update:

– The IPA’s rechargeable battery has been changed from NiMH to Li-ion, which adds good amount of runtime: 350mAh vs. 300mAh for the NiMH!

Forum Timezone: America/New_York
All RSS Show Stats

Jon O'Neil
Susan Lawrence

Top Posters:

Andrew Caldwell: 4

wvmaine: 2

sean: 2

James David Lawrence: 1

Robert Garthe: 1

matahaka: 1

diskobean: 1

Newest Members:


Angelo Esposito








Colin Sullivan

Forum Stats:

Groups: 1

Forums: 6

Topics: 10

Posts: 35


Member Stats:

Guest Posters: 0

Members: 545

Moderators: 0

Admins: 2

Most Users Ever Online: 13

Currently Online:
2 Guest(s)

Currently Browsing this Page:
1 Guest(s)

Shopping cart


No products in the cart.