dincz

OK, I'll probably take the plunge anyway and be a member of a very exclusive club.

If the amp is still working, there can't be too much wrong with the transformer. It may simply be rattling against the chassis. Try tightening its mounting screws.

The second hand market is severely limited over my way but one of these has come up for sale. On paper it looks like it should offer what I'm looking for EQ-wise (low shelf, lo mid parametric, high mid parametric, high shelf) along with DI, compresser and expander plus the flexibility of separate ins and outs for each stage. Any real world experience you'd like to share?

I haven't read this thread in detail so sorry if I'm totally off track here. If there's not enough clearance to swing the allen key more than a few degrees, couldn't you slip a matching size ring spanner over it (using the long end of the "L") before inserting it into the screw head? Or cut a length off the allen key and use a socket spanner.

Not much detail here but at least Thomann replied within 10 minutes!

BDI-21? Also cheap and useful, but the appeal of the HB is the 3 band EQ.

Looks like a useful piece of kit for the price. Anyone used one? [url="http://www.thomann.de/gb/harley_benton_bdi2000.htm"]http://www.thomann.d...ton_bdi2000.htm[/url]

Don't know if this is true in the real world, but I'd expect switchable mains voltage to be more common in amps with switch mode power supplies. In any case, 100V - 250V voltage tolerance (without a switch) is not unusual in SMPS.

Small Bear are being a bit sloppy with their notation. Where they've written mF they mean microfarad (µF). Millifarad is not normally used for capacitors. Non-polarised types include ceramic, polyester etc. The common polarised types are electrolytic and tantalum (tant). Symmetrical clipping - both the positive and negative sides of the signal are clipped equally. The diodes are the same but the way they're connected determines whether the clipping is symmetrical or asymmetrical.

Referring to ohmage is pure impudence.

[url="http://www.youtube.com/watch?v=I3EvBiDloRQ"]http://www.youtube.com/watch?v=I3EvBiDloRQ[/url]

Just to complicate things even more: [url="http://hyperphysics.phy-astr.gsu.edu/hbase/sound/pitch.html#c3"]http://hyperphysics.phy-astr.gsu.edu/hbase...d/pitch.html#c3[/url] Details About Pitch Although for most practical purposes, the pitch of a sound can be said to be simply a measure of its frequency, there are circumstances in which a constant frequency sound can be perceived to be changing in pitch. One of most consistently observed "psychoacoustic" effects is that a sustained high frequency sound (>2kHz) which is increased steadily in intensity will be perceived to be rising in pitch, whereas a low frequency sound (<2kHz) will be perceived to be dropping in pitch. (More detail) The perception of the pitch of short pulses differs from that of sustained sounds of the same measured frequency. If a short pulse of a pure tone is decaying in amplitude, it will be perceived to be higher in pitch than an identical pulse which has steady amplitude. Interfering tones or noise can cause an apparent pitch shift. Further discussion of these and other perceptual aspects of pitch may be found in Chapter 7 of Rossing, The Science of Sound, 2nd. Ed.

Is this a world first - a Behringer thread that didn't descend into myth, legend and folklore?

Thanks for all the feedback. I've since poked around on the web and it seems to be a well known phenomenon. The consensus seems to be: 1 Keep the volume down. 2 Especially the bottom end - a tinny headphone mix works better for pitch perception.

I've recently been practising using headphones and found that as I increase the volume, the apparent pitch of any given note drops as much as a semitone. It really showed up when I recorded a vocal part while monitoring previously recorded tracks on headphones. The vocal track was noticably sharp (around 25 cents) on playback. My ears are normally very good (much better than my fingers) and I'm known as a pitch pedant, so this is a concern to me. Has anyone else come up against this problem and found a solution?

[quote name='UNITY GAIN' post='1227027' date='May 11 2011, 04:32 AM']On the poweramp there is only one input per channel. My mixer has both a Left and Right output. Do I have to use both the left AND right outputs to get stereo? Or if I use just one of them is that mono? I assume to use both the right and left output I'd have to use a "Y" cable or something so that I could integrate both the Left and Right output into the poweramp's single input. Correct? Thanks again for the help.[/quote] If you want stereo then yes, you need to use both outputs from the mixer - L to one power amp channel and R to the other. If you combine the L and R mixer outputs with a Y cable (not a good idea from the point of view of impedance) then you're back to mono.

My voice coil doesn't care where the magnetic field comes from, so I'm all for weight reduction in cabs.

[quote name='Count Bassie' post='1168542' date='Mar 19 2011, 06:41 PM']Hi kids, So I've posted ad nauseum about my MK IV head, and it's working fine except that last night I was plugged into a wall (110) and with the UV light on there was a little red LED labeled "ECI" blinking. I think it's better if that is not blinking, or on at all... does anyone know what ECI stands for, and what it indicates? Thanks![/quote] Google is amazing - and leads you back to basschat: [url="http://basschat.co.uk/index.php?showtopic=51769&view=new"]http://basschat.co.uk/index.php?showtopic=51769&view=new[/url]

If you manage to get its output up from 60W to 100W, you probably won't hear a great difference. A little over 2dB in fact - barely noticeable.

[quote name='mart' post='1141895' date='Feb 25 2011, 11:15 PM']Guitarist magazine had a review of the combo last month and had the following comments about the use of the valves "The single channel runs off a lone ECC83 [i]preamp[/i] valve ..." and then, later, "[i]Power[/i] comes from a not-that-common ECC82 dual triode that's using its two halves to run in class A/B push-pull configuration ..." I can't say that I understand much of that, but I read it as saying that it's using an ECC83 for the preamp and an ECC82 for the power amp, i.e., the output stage is not solid-state. Is that a fair reading? Of course, Guitarist may not know the facts, but that reads like something off a press-release/info pack.[/quote] That does seem to be the case. I found a company selling replacement valve sets for it - 1 x ECC83 and 1 x ECC82. I was surprised that Blackstar specify only a minimum load impedance (4 ohms), which is what made me wonder.

[quote name='obbm' post='1141692' date='Feb 25 2011, 09:23 PM']Before going any further I would want to see the wiring schematic of said amplifier. I suspect that getting one is a bit like "blood/stone". [/quote] I had a poke around and found this: [i]"Thanks for the enquiry. You can use the HT-1 with cabs of a minimum of 4 ohms without causing damage to the head. In other words you can use your cab with the HT-1. Kind regards, Tom Blackstar Customer Services Tel: +44 (0)1604 652844 Email: [email protected]" [/i] .... which makes me wonder if the output stage is actually solid state.

[quote name='mart' post='1141242' date='Feb 25 2011, 03:12 PM']"when a lead is connected here the combo’s internal speaker is disconnected", suggesting that a speaker isn't needed.[/quote] Not to be taken too literally. What they mean is that no signal is sent to the speaker, almost certainly not that the speaker is physically disconnected.

[quote name='obbm' post='1140939' date='Feb 25 2011, 11:48 AM']Even if plugging in headphones does disable the speaker output, the reflected load of the speker through the output transformer will have an effect on the output valve.[/quote] There is no reflected load as there's only a small DC current passing through the primary of the output transformer, and therefore absolutely nothing going on in the secondary.

[quote name='mart' post='1140911' date='Feb 25 2011, 11:22 AM']So I can run it without a cab? That would be convenient.[/quote] Yes, as long as you understand the risk involved in forgetting to reconnect the speaker before pulling the headphone plug.

[quote name='mart' post='1140641' date='Feb 25 2011, 12:21 AM']the power amp is still on and so needs a load, but is disconnected from the preamp[/quote] The power amp needs a load only if it's amplifying a signal. If the headphone jack interrupts signal from preamp to power amp, then you don't need a load - and the unnecessary 8 ohm resistor will be stone cold. The problem running without a load is remembering every time to reconnect the speaker before you pull out the headphone plug.