Oxblood

Oh for goodness' sake.

[url="http://cgi.ebay.co.uk/GIBSON-EPIPHONE-BASS-TOP-ROCK-PREVIOUS-owner-LOOK_W0QQitemZ190138476227QQihZ009QQcategoryZ2328QQssPageNameZWDVWQQrdZ1QQcmdZViItem"]eBay listing[/url]

[color="red"]THIS LINK DOES NOT WORK BECAUSE THE FORUM ENGINE KEEPS GARBLING IT. See Below. Sorry. [/color]

[quote name='jwbassman' post='43900' date='Aug 10 2007, 06:08 PM']so it's no good then [/quote]
Aww, now let's be fair: I didn't say that. I'm sure it would work very nicely as a door-stop.

Just a quick anti-recommendation. Don't go anywhere near the HiWatt Maxwatt B20. I've just tried one. It stinks worse than a very stinky thing that's been left out to go bad and then painted with sewage just to make sure.

Recently I've been thinking about getting a small practice amp. The trusty old Peavey MicroBass (secondhand) is top of my list of possibles, but as I was in town today, I took a trip down Denmark St, where I saw the HiWatt Maxwatt B20. It looked quite pretty, so having nothing better to do, I thought I'd give it a try. Oh dear.

PRICE PAID:
It was on sale at two prices, depending on whether you want the old style case (£89) or the slightly bigger, boxier new one (£129).
Didn't buy either!

FEATURE LIST:
20 Watts (supposedly)
10 Inch Speaker
High and Low Sensitivity Inputs
3 Band EQ
Presence Control
External Speaker Output
Headphone Jack
Limiter

FINISH: 5/10
Looks quite nice.

SOUND: 0/10
Absolutely dreadful. This has to be one of the weediest sounding practice amps I've ever experienced. I've heard louder transistor radios. Any attempt to get it near to a usable practice volume (and believe me, I'm not talking loud here - just audible) results in it overloading horribly. The EQ section is a joke: the mid control has no effect at all! I tried both 'styles' of the amp, and both were equally awful.

RELIABILITY: n/a

CUSTOMER SUPPORT: n/a

OVERALL SCORE: 2.5/10 (on looks alone)

SUMMARY:
AVOID THIS PRODUCT. I could make a louder - and more attractive - noise by farting into a tin can.

Well, it's not just a problem for European users, it seems. Get a load (but not too much of a load - don't want to trip any circuit breakers) of this from across the pond:
[url="http://www.talkbass.com/forum/showthread.php?t=190882"]TalkBass thread[/url]

From what I'm reading, the DB750 certainly is "a truly exceptional amp in conception, design and performance" - but not in a good way! IMHO Aguilar's design staff need to be dragged into the village square and pelted with dung/rotten veg/concrete blocks over this. It's outrageous to market a piece of gear which you know damn well will be powered off ordinary domestic mains supplies, and yet not take this reality into account when designing the power supply stage. It really isn't difficult to design a power supply that has 'soft start' behaviour built in.

[quote name='alexclaber' post='43540' date='Aug 9 2007, 11:10 PM']I'm sure you can get a used Korg for similar money if you're patient.

Alex[/quote]
Like I did! £50 and works a treat. (Thanks, Alex)

Re. Koch bass amps: in an already engorged marketplace and working against stiff competition, sales were just never firm enough to achieve market penetration.

If you're replacing both (and if you can't find one of the exact Celestion driver, then you will have to), don't forget that you don't have to find 16 Ohm units. A pair 4 Ohm drivers wired in series will do the job just as well.

I find it very hard to believe that Ashdown are no longer using 16 Ohm drivers at all, but assuming this is true, then in a 2x10 8 Ohm combo they [u]must[/u] be using 4 Ohm ones. There's no other way to achieve an 8 Ohm load with two drivers.

As soon as I read the original post (rather late in the day, alas) it was pretty obvious where the problem lay. The Superfly has a Class 'D' power section, doesn't it? Oh dear. Not good. Class 'D' power supplies are very efficient and very light, but unless they're also very carefully (read "expensively") designed, they spew out copious amounts of high frequency/RF noise. In my opinion this should effectively disqualify them from use in an any serious audio environment. And yet, they're becoming gradually more common in instrument amps - even in some valve amps (MarkBass, for example), despite the fact that high impedance valve circuitry is naturally more noise-sensitive than SS. I can't understand why the manufacturers are doing it.

Oh, wait a minute... I get it: they're CHEAP!

Reminded me of HS too at first, but the longer I listened, the more I realised that she leaves that one-note honker drowning in her wake. Next to Dorsey, HS sounds like bleedin' foghorn.

What a range!

Thanks for the wayback machine link, Pete - very useful! As for it's possible re-appearance, we can but hope. In the meantime I'm tempted to download every diagram I can lay my hands on and burn it all to disc while I have the chance!

This morning I went to visit one of my favourite web resources: "Schematic Heaven". In case you're unaware, as the name suggests, it's a repository of Amplifier Circuit Diagrams.

It's gone.
It disappeared briefly a wee while back, but soon returned. This time, though, there's an "account suspended" holding page from the host, which suggests that either the site has breached some legal stuff (copyright perhaps?) or that the owner has failed to pay his hosting bill.

There are other such resources on the web, but this was a particularly good one, and losing it is a great shame. I hope it re-surfaces somewhere.

Just finished putting her together last night...



This is the new front end of my rig. It's two-channel affair, with independent pre-amps for each pickup. The outputs of these are then commoned via a transformer/isolator, to give a mono feed to the power amp. You can see what's in there by reading my signature, but just for the record, here's the list again:

From the bottom up:
1) MindPrint [i]enVoice[/i] recording channel (3-band parametric EQ with valve saturation/compression).
2) Peavey TB Raxx all-valve pre-amp. The first stage has a Fender tone stack; the second is a Baxendall.
3) Korg DTR-2. This is not part of the signal chain. It is fed from an auxiliary line output of the Peavey.
4) Input/Output panel. The XLR socket takes the signals from the bass (stereo unbalanced). The jack socket is the line output to the power amp. Next is the master output level control, and finally a mute switch. The two little screws in the middle of the panel hold in place the hidden item: an ART DTI box. This handy bit of kit contains two signal transformers. It enables any combination of two sources (balanced or unbalanced) to be fed through without developing any hum loops.

You'd think that, somewhere in the chain from manufacture to retail sale, somebody might have had the foresight to get out a tape measure...

Nice one, Alex. Coherent indeed.

The mention of Gain and Volume brings to mind one of my pet bugbears: the habit that many manufacturers have of mis-labelling the controls on amplifiers.

First let's deal with the worst culprits. It seems to be a commonly held view among certain companies that in selling to musicians, they are ipso facto selling to idiots who are easily impressed by shiny objects and flashing lights, and to whom they can pretty much spin any nonsense they wish. This leads to products on which perfectly normal Signal Level and EQ controls have been given stupid, subjective names like "bite", "heat", "balls" etc. Does anyone really find such descriptions useful? I doubt it. Personally, I just find them embarassing, and I'm sure I'm not the only one who immediately ignores any product with such twaddle printed on its panel.

However, even among those companies who avoid such inanities, there is still a common practice of mis-labelling going on, and one that leads to endless confusion among non-technically minded users. I'm talking about all those amps (including well-respected, high-end products) that have an input level control which, bizarrely, is labelled "Gain", and may well be accompanied a bit further down the panel by another knob marked "Master Volume", "Master Gain" or "Output Level". In nearly every case, such labels are wrong!

And let's not forget that old favourite, "Volume Control". We're all used to saying that, aren't we? Yet even that is a piece of 'creative' labelling - a hangover from the days of domestic wireless sets.

In a typical instrument amp, the first "Volume Control" you find is simply a pot placed in the signal path - just like the one we find in a passive guitar or bass, between the pickups and the jack socket. All it does is act as a [i]potential divider[/i]: a variable resistance that bleeds some of the signal away to earth and allows the rest through to the next amplifying stage. Turn it up full, and all (or nearly all) of the signal gets through. Like a water tap, it's a purely passive device. It can't give out more than is being fed in. In some amps this first pot is positioned directly after the jack input itself, but more commonly these days it is placed after an initial amplifying or buffer stage. Either way, the effect is the same.

Likewise, the "Master Volume" or "Output Level" control is another passive pot, placed at the point where the signal leaves the pre-amp/EQ circuitry and is being fed to the input of the Power Amp.

What it [i]doesn't[/i] do, in either position, is alter the GAIN of the amplifying stage of which it is part ...but that doesn't stop some manufacturers calling it a "Gain" control.

Confused? I'm not surprised!

So, just for the record:
A true Gain control works by modifying the operating conditions of an amplifying device (varying a DC control voltage on an Op-Amp, for example) and in so doing actually determines how much gain that device can apply to whatever signal it is being fed. Genuine Gain controls are usually only found on professional studio equipment, mixing desks and so on. They are not used alone, or instead of passive pots. Both are used together, as they have different roles to perform. They're part of the variety of control options that make such equipment flexible enough to accept and process signals from the widest possible range of sources, and do it efficiently, with the best possible signal-to-noise ratio.

I think that's it. Don't want to hijack Alex's excellent thread. I'll shut up now.

[quote name='TPJ' post='38852' date='Jul 30 2007, 11:20 AM']Don't forget to check out [b][url="http://www.davehallamps.co.uk/Products.html"]Dave Hall's stuff[/url][/b] as well. Lots of options.

There is also [b][url="http://www.george-dennis.cz/pages/bassamps.htm"]George Dennis valve amps[/url][/b][/quote]

Stone me! That George Dennis stuff looks tasty. Thanks for the link, TPJ.

The Bassic Tube 200 Head is €1097, which works out to around £750. Dearer than a Traynor YBA200 but not bad!

ADDED LATER:
I've just looked at the user manual. Along with the usual Gain, Treble, Middle & Bass, the panel has knobs called "HEAT" and "BALLS". Shame, that: pretentious names and completely meaningless. The sort of nonsense guitarists like.

Re. Stereo valve power amps, it might be worth watching eBay for the 100 Watt-per-channel version of the Marshall Series 9000 rackmount jobbies. There's a 50W per channel version, which is far more commonly seen, but I doubt it would have nearly enough power. Also, a word of warning: these Marshall 9000 amps are stereo only - i.e. NOT bridgeable. And, of course, they may not be suitable as they were designed for guitarists. Which brings me to the following....

On the subject of 'guitar' valve amps in general:
As a rule, any powerful valve amp designed/marketed for guitar players should be treated with caution by bass players, because:

1) If it is aimed at the needs of the heavy metal guitarist, it will have been designed with very high-gain pre-amp stages which slip into distortion easily, and a tone stack that isn't really bass friendly.

2) The output transformer won't have been specified with accurate LF reproduction as a priority. Indeed, it may have been deliberately designed with a limited response in the LF range as a cheap way of avoiding 'motorboating' instability in a high-gain amp.

3) Likewise, the power supply may not be hefty enough to deliver clean power in the LF when you need it. You may get 'sag' - a form of compression which occurs when the power supply stage is unable to deliver enough current to 'track' the transients of your playing. This effect is most common in amps whose power supply uses valve rectification. Many guitar players like this effect, but is virtually useless to bassists as it robs all the attack from your notes.

Of course, I'm speaking in very broad terms here. There are numerous honourable exceptions to the above caveats: Burman, Sound City and HiWatt come to mind for starters. In general, though, if you want to play safe, go for an amp that is either specifically designed for bass guitar or is of unassailable 'HiFi' quality (such as a highly respected brand of PA amplifier). If you must use a 'guitar' head, choose one that has a known track record as being OK for bass.

I can't claim the credit for that. If you go to [url="http://www.ricksuchow.com/press-group-112.html"]the link that stewblack provided[/url], you'll reach the website of a bassist called Rick Suchow. I believe he did the isolation. The only way it could have been achieved, to the best of my knowledge, would be if Motown were recording in multi-track originally - or at least laying down the bass on its own track.

[quote name='Old Horse Murphy' post='37980' date='Jul 27 2007, 09:38 PM'][b]These 2 guys are my heroes[/b] and to me, it doesn't get any better than this!![/quote]

SNAP! Couldn't agree more, Mr...er...HorseMurphy.
JB's work with Cream was what made me want to get into bass playing in the first place. I had the privilege of seeing Rory at Liverpool Empire in the mid 1970s - around the same time he was doing his Irish Tour. Competely blew me away. What a genius - and what a lovely guy! Talent of a God and the ego of a fruit-fly. If only they could all be like that!

OOOPS!

Sorry, folks. Links now fixed (although the link given by stew is just as good and contains more tracks).

Agreed, stew. I'm with you all the way on Bruce Thomas, too. Bloody genius. And then there's Norman Watt-Roy..... The Blockheads would have been SO much less of a rhythm machine without him.

[quote name='Hutton' post='36716' date='Jul 25 2007, 08:56 AM']Even if you don't like Motown which is of course your right, I am sure that you would appreciate the bass playing of James Jamerson and Bob Babbitt. They are well worth a listen[b] if you can blot out the rest of the song[/b]![/quote]

At your service, sir!
Here are links to three mp3s of James Jamerson at work, isolated from the rest of the instruments. Educational stuff!

[i][b][color="#FF0000"]Folks...
Please DOWNLOAD the files, don't play them off my server - I'll get into trouble with my ISP.
Windows: right-click the link and select "Save target as..."
Mac: Ctrl-click and select "Download linked file"
Thanks,
Ken[/color][/b][/i]

[url="http://www.steamingaudio.myzen.co.uk/basschat/wgo.mp3"]What's Goin' On? (Marvin Gaye)[/url]

[url="http://www.steamingaudio.myzen.co.uk/basschat/standing.mp3"]Standing In The Shadows Of Love (Four Tops)[/url]

[url="http://www.steamingaudio.myzen.co.uk/basschat/reachout.mp3"]Reach Out, I'll Be There (Four Tops)[/url]

BTW: both of these tracks have a looong silence at the start, because he doesn't come in for several bars. Be patient.... It's worth it!

Hi King of Loss,
I would just add what you probably know already: bridging the outputs of a stereo/2-channel amp can only be done with an amp like the one you've been looking at - i.e. one that is designed to be bridgeable.

Just in case anyone out there gets a burning (good choice of word!) desire to common up the outputs of any old stereo amp. Bad idea!

Yep - assuming we're talking solid state here and of course your 4 Ohm load is not below the amp's recommended minimum impedance - the one with the 8 Ohm load on it will just be working less hard.

[quote name='99ster' post='37632' date='Jul 27 2007, 02:50 AM']If you talk to any amp tech they'll all tell you the same story - they get loads of business from repairing Ashdown gear because it keeps breaking.
And that can only happen because they're poorly designed, or use cheap sh*t components, or both.
That tells me all I need to know...[/quote]
I'm convinced that it's all down to poor Quality Control in the far eastern production facility. It certainly isn't the design: that was done by Clive Button, no less: he who designed all the really good Trace Elliot stuff. I doubt, too, that they're cutting corners on component quality - at least not on purpose. I mean, after all, no company with any sense would willingly to make themselves hostages to fate by deliberately using crap components. The real variable in the mix, though - and the one over which they have the least hands-on control - is HOW the things are assembled. The unavoidable fact is that if your HQ is in the UK and you've outsourced your production to an emerging economy on the other side of the planet in order to save money, then however well-intentioned you may be as a company, you have removed yourself from what's actually happening on the factory floor and made yourself reliant on the reports/promises you're being given by the managers of that facility.

It's all very sad, isn't it? If you really want an ABM (and a proper, British-built one is a marvellous piece of kit), I'd go hunting for a real early one, with the white push buttons and black sliders. Nothing later than an EVO, anyway.

BTW: I always wondered what "RC" stood for in the name of these current products. Does it stand for "Republic of China", by any chance?