All about Tubes, Tube Circuits, Tube Gear

Wednesday, November 26, 2014

Ashly PQX-572 Dual Parametric 7 band EQ

This is a simple, practical Parametric EQ design,
which is very flexible, and replaces/increases the options
on any input channel of your mixer via insert.

It can also be very effectively used for tone shaping of
PA systems via inserts on the Main Outputs of your mix.

One example use would be to dedicate one "channel"
for a mono stage-monitor/foldback mix, and the other
"channel" for the Mains FOH (Front of House) Mono mix.

It is good enough quality to also apply to a simple mixdown,
for testing or tone-shaping or corrective EQ.

On some units for sale used, you will see damaged front knobs.
The front knobs stick out a significant distance from the panel,
making them susceptable to damage, unless precautions are taken. A metal railing or recessed mounting is advisable.

The rear XLR / TRS in/out as well as screw-strips make
hookup very flexible.

I suspect that some units get damaged in live gigs due to abuse, rather than poor construction.

TOA E-1231 Series 1000, 31 band Graphic EQ

Two things commend these 31 band EQs:

(1)  They were manufactured in Japan, where quality control standards are very high.

This results in quality performance of electronic circuits,
and also reliability over time.


(2)  These particular units have full size, high quality slider-pots,
with a professional quality feel usually found only on high end stereos. 

They are very smooth and have a nice resistance to the touch,
and hold their positions very accurately.   The Knobs themselves
are also well designed for visibility and durability.
All three units I have purchased have all their knobs and
exhibit no damage from 'roading'.


The one drawback is a minor one.  These units come
by default without input or output transformers,
and are expected to be hard-wired into permanent systems,
such as church and public address PA systems, and so
TOA has left it as an option to order them with transformers
installed.   Thus all my units came without transformers.

In fact, Graphic 31 band EQs are best used next to your mixer board when doing live gigs, so transformers are not necessary, since the EQs can be inserted at the board,
and the unit shouldn't need to drive long balanced lines.

In case one does want to install them say between monitor sends and the stage, and still keep them next to the board,
one will probably want either output transformers (only),
or have input transformers on your power amps. 

The real issue is that they are by default only provided with
terminal strips, which means you must either install
XLR / TRS jacks, or make up short cable adapters.

This is not a real problem as there is plenty of space inside
the units and on the back panel for additional jacks.

I installed TRS jacks on two of my units to make them
easy to plug in and remove, as per the photos.