Tuesday, March 14, 2006

Blast from Bournemouth

Just had this great reaction from Andrew Higginson in the UK which I thought I'd post here in full (with his permission).

I'd probably better say who I am first. I work at Bournemouth University and look after the radio studios in the Media School. I'm also a part time student on the MA Radio Production course lead by Sean Street and Hugh Chignell.

We have over the last 2 years gone for the Marantz PMD 670. We now have over 30 of these. When we bought the first batch, the 660 had not been released, and on getting the second lot, there were a lot of very bad reviews for the 660, so we left these. We were due to be looking to replace our remaining MD machines this year, however as the solid state market is in a point of flux, we are leaving it for another year.

Reading through all of the technical reviews, the main problem with the 660 seems to be distortion on the mic inputs. It seems to be a design issue and not something that can be sorted with a firmware upgrade. There is a very good discussion on these issues on the Transom forum.

The Microtrack has had a lot of bad press due to the phantom power on the mic sockets. In the original spec, it was meant to be 48v. In the production model, this had fallen to 30 volts and some mics don't like this.

I've had a play with one of the HHB pre production Flash mics and I must say I like it. It is simple and easy to use. It has 1gig of memory on board and looks like a normal memory stick drive to any computer it is connected to. It also takes standard AA batteries so it is not too much of a problem on the road. However, there is a cost. The figures I have heard is about £700 a unit! Andrew Hingley at HHB should be able to tell you more.

One thing to look out for is the mics you use with the recorders. Out of all of the dynamic reporter mics on the market, the Audio Technica has the highest output and the Beyer M58 the lowest. There are also some Condenser mics out there as well that have a higher output level. Email me if you want more info, but the main issue is how well the mics drive the input stage of the recorders. The lower the mic output, the more gain you have to use and the more hiss you get.

Looking through the specs of ENG omni mics, there is a fair difference between different mics. There is a lot of mention about the low output levels of dynamic mics. However, some are a lot lower than others. From the specs on the manufacturers sites, the following a listed.

D230 2.5 mV/Pa (-52 dBV), 320 Ohms

Audio Technica
AT804 -49 dB (3.5 mV), 600 Ohms
ATM10a -45 dB (5.6 mV), 270 Ohms

M58 1.3 mV/Pa ≡ -58 dBV, 200 Ohms
MCE58 4 mV/Pa, 370 Ohms

RE50N/D 2.0mV/Pa (-51dB), 150 Ohms
RE50 -55dB, 150 Ohms
635 -55dB, 150 Ohm
635n/D 2.0mV/Pa (-51dB), 150 Ohms

MD42 and 46 2.0mV/PA, 350 Ohms
K6 / ME62 31mV/PA, 200 Ohms

VP63A -51.5dBV/Pa (2.7mV), 300 Ohms
SM63 -56.5dBV/Pa (1.5mV), 150 Ohms

Looking through all of these specs, yes I know that they are not being tested under identical conditions, but it does show a fair difference in output levels. In the past, I have found the Beyer M58 to have a lower output level than the Audio Technica AT804 and where the 804 worked ok, the M58 was too low. Teac portable DATs are one example. The problem I have had with the AT804 is that it is very short. It is only 6 inches long compared to 10 inches for the M58. Audio Technica have now released the AT804L which is about 10 inches in length to allow them to fit into the market with the likes of the M58 and D230.

As mentioned before, Beyer have produced the MCE58 as an answer to the portable MD market. On their website they say "Its unbalanced output supplies a very high level which allows direct connection to mobile DAT and MD-machines." From what people have said, this is a good mic.

If you want a good high level from a mic, the Sennheiser K6 / ME62 has a very high output compared to other Dynamic and Condenser mics.

Personally, I have a Sharp SR50 and a couple of AKG D230 mics. It seems to work ok and I do have manual level control during recording. I've got 2 of the mic cables mentioned in my last post plus a Y splitter for the mics. This is a Stereo Minijack plug to 2 Minijack sockets to allow 2 mics to be connected.

Somebody mentioned about handling noise in an earlier post. I take it you are holding a loop of cable at the mic end. Loop the cable once and hold the loop against the mic with the same hand you are holding the mic with. This will reduce a lot of the handling noise. I let my students hear the mic cable being tapped about 12 inches down from the mic without the look and it picks up a lot of noise. With the loop, there is very little noise.