richardash1981 Posted November 16, 2013 Share Posted November 16, 2013 Today's CPC "Big Winter Sale" has several of the Pulse-branded microphone mixers and pre-amps going for very silly money (evidently no-one bought them at the RRP - which isn't surprising). Has anyone used them to know if they are bearable or not?http://cpc.farnell.c...8?Ntt=DP3252428http://cpc.farnell.c...8?Ntt=DP3253028I'm thinking of extra mic channels for speech mics in a church/hall, radio mic inputs via the otherwise unused line inputs of budget mixers and similar applications - so not vastly taxing. Are they usable, or so low gain / low clipping / noisy that I shouldn't bother? Link to comment Share on other sites More sharing options...
GaryNattrass Posted November 17, 2013 Share Posted November 17, 2013 The mixer looks identical to the ART promix 3 that I have and it is fine and very useful, setting gains can be a challenge as there are no meters but they are quiet and clean. http://www.thomann.de/gb/art_promix.htm The dual mic pre-amp is an absolute bargain as it has phantom power and even a limiter built in so is ideal for a lot of applications I would think the quality will be fine for most non critical applications and I have bought a couple myself for use on OB's and for coms. Link to comment Share on other sites More sharing options...
richardash1981 Posted November 17, 2013 Author Share Posted November 17, 2013 Thank you for that, looks like well worth picking up both for the prices they are available at. The mixer will basically be used to switch between single microphones for readers one at a time, so levels shouldn't be too hard to deal with. I had a suspicion that some of the Pulse gear is cloned ART, which does bode well for it's quality (I've had a couple of ART passive DI boxes which have done nicely). Link to comment Share on other sites More sharing options...
GaryNattrass Posted November 17, 2013 Share Posted November 17, 2013 I paid £80 for my ART mixer so yes those prices are very good, the peak LED's are at least an indicator of too much going in the front end and at least there is a headphone socket for a quick check for any quality issues. Link to comment Share on other sites More sharing options...
richardash1981 Posted November 21, 2013 Author Share Posted November 21, 2013 Both arrived. Initial impressions are that the MicroMix3 is nice, does the job without complaints. The mic inputs are not silent but not noisy enough to be an issue. Output is not very high level (well below +4dBu) but enough. The dual mic preamp is less nice - it's an awful lot noisier than the preamps in my Behringer Xenyx 802 I was testing with (for the same gain on the same signal, from a Sony battery powered electret condenser). Should be OK for hot outputs of radio mic receivers, but I certainly won't be recording through it! Pity, as it's well built and batter operation is convenient - although beware it does not have an input socket for a mains adaptor! Link to comment Share on other sites More sharing options...
GaryNattrass Posted November 21, 2013 Share Posted November 21, 2013 Will post my findings on the pre amps once I get some time to test them. Link to comment Share on other sites More sharing options...
richardash1981 Posted November 21, 2013 Author Share Posted November 21, 2013 I've taken the lid off (or rather, bumpers and ends off) the Pulse MPRE Dual to have a look at the circuit inside. It turns out that the audio path is a TL074C and a TL072C op-amp! So some very ordinary op-amps doing the work, which does rather explain the performance achieved. In the power supply section there is a TC4096UBP Hex CMOS inverter, which (with a bunch of diodes) presumably forms some charge pumps / voltage multiplier to produce the main supply rails and the +48V for the phantom power (R1/R2 are phantom power for Ch2, R41/R42 ditto Ch1. C1-4 are 10u 50V non-polar input caps). This seems to work perfectly well, despite it's simplicity. Not yet sure how the limiter or peak lights work, but there are 8 off TO-92 transistors in that corner of the board which are presumably responsible. The board is double sided, mostly without a ground plane (which is a pity, but I suppose in an extruded aluminium case doesn't matter much). It's not very easy to trace out, because there are quite a lot of traces under components which you can't see. The board is marked "PCQ15NC51B" and "DMP-2", the latter showing what the same product is sold as Nady DMP-2:http://www.musicians...crophone-preampI'd be annoyed if I had paid £60 for a TL074 based preamp!The manual is better spelt and typeset than the Pulse one, but otherwise identical. I'm strongly tempted to remove the TL074 in favour of a pair of SSM 2019s if the power supply will run them and I can work out how to connect them to the gain controls! Link to comment Share on other sites More sharing options...
GaryNattrass Posted November 23, 2013 Share Posted November 23, 2013 I had a quick play with the mic pre-amps this morning and can agree that they are not the best or quietest in the world but certainly very useable for my intended application as phantom power providers and line level boosters for effects mic's on location. They work better with capacitor mic's and the limiter seems to do a half decent job of preventing any overloads as a front line device. The build quality is OK but hardly sound devices and the pots and switches are the usual domestic type but for the price I can't complain as it is always useful to have mic to line amps for boosting coms or IFB's for outside broadcasts. Will do some more tests when I can, Link to comment Share on other sites More sharing options...
dbuckley Posted November 23, 2013 Share Posted November 23, 2013 The build quality is OK but hardly sound devices...Groan... Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.