Al Heeley

I'm selling a Marshall 150W combo at the moment for £150. 7 band EQ, valve and solid state pre-amp, blendable together. Great for practive and small gigs. [url="http://basschat.co.uk/index.php?showtopic=34623"]http://basschat.co.uk/index.php?showtopic=34623[/url]

OK I've wired this into my P-bass. I fitted a mini DPDT switch [on-on-on] and 2 caps to the end pair of lugs. It sounds good - the trebles are preserved down to low volumes but to be honest the shift in tonal response with the different value bleed caps is quite subtle - maybe a little redistribution of the mid frequencies is heard, if anything. Here's the spec: 250k vol + tone pots with a 0.047uF cap on the tone pot. treble bleed: 220k resistor in parallel with choice of 560pF cap, 2.2nF cap or both together. What is really different is the tone shaping of the tone pot. Not the normal drop off of tone but again a shifting of the mids, quite noticable and pleasing. The top end sparkle drops off a bit, but it seems to reshape the mid range more. I've not tried it thru the main gig amp at proper volume yet, but will give it a test run tomorrow at the band practice. Here's the circuit: Here's the bass with the toggle switch:

Heres a couple of Tubescreamer clone PCB's in progress - got the bug rekindled a few months ago. This sounds bloody marvellous! One of the sweetest harmonic distortion pedals I have come across. The original (Ibanez) tubescreamers were seen by some as the holy grails of distortion stompboxes. Apologies for hijacking your thread!

A quick search for A/B/Y boxes should give you the solution, but I guess you need something with a line level too, so the input levels can be matched.

Kent armstrong ric neck toaster. Bought one to put in my replica build. [url="http://www.wdmusic.co.uk/product/Replacement_%22Toaster%22_Pickup_Front_SRK1F"]http://www.wdmusic.co.uk/product/Replaceme...kup_Front_SRK1F[/url] Note: ric basses use9d) same neck pups for guitar and bass. Interchangeable. Even though its 6-pole. Quirky lot, adds character, apparently.

These graphs show the change in treble response as vol is rolled off, for a 100k and a 220k resistor in parallel with the 1nF cap: You can see that with a larger resistor, the treble enhancement is increased as the volume is rolled off. For this circuit a 56k resistor gives a more natural flatter profile over the volume range. And here, if you whack the cap up to 47nF (0.047uf = sort of cap value you would have on a tone pot) you get a mid-boost response when you turn the vol down:

Heres some graphs I snapped and photoshopped together, this shows a virtual parallel treble bleed in action, helping to preserve the high frequencies as the volume is rolled off. To be really accurate you have the ability to input your pickups individual resistance, capacitance and inductance, as well as choose a 10 foot, 20 foot cable or buffer. What an amazing spreadsheet model!

Oh boy, have a look at this: [url="http://people.smartchat.net.au/~l_jhewitt/circuits/GuitarFreak_2_0.xls"]http://people.smartchat.net.au/~l_jhewitt/...arFreak_2_0.xls[/url] Electronics heaven! Fiddle with the resistors, pots and caps and pickups and watch how the frequency responses change.

[quote name='alexclaber' post='412840' date='Feb 18 2009, 10:59 AM']...British labour isn't much more expensive than other European countries but our labour laws and our governments' long-term disinterest in manufacturing makes it much easier to close down UK factories and there are fewer incentives to open UK plants.[/quote]Sad but true. The labour cost comparison though is not with Europe, it's UK verses India or China. This Marshall came from their Indian factory. The business I work for is now owned by an indian company and we get to see some of the real gap in salaries for the guys assembling the units. It is substantial, otherwise why would all the industry more to the far east/asia. We also have a Chinese office and see the labour costs there. We cannot hope to compete on assembly and manufacturing costs, but it is more than just the salary levels, its all the employee benefits that you are used to getting in Europe, like helath care, pensions, etc. The cost of these in India is a fraction of what UK employers have to pay.

[quote name='YouMa' post='412665' date='Feb 18 2009, 02:34 AM']Has anybody got any plans for jazz or precision bodys so i can make a template for cutting purposes. I know you can buy them but i dont really want to have to fork out 30 quid. Cheers Mark.[/quote] I've got a full size P-bass plan, send me a pm with yr address.

[quote name='johnnylager' post='411690' date='Feb 17 2009, 08:10 AM']0.047µF. [url="http://www.guitar-mod.com/wiring/jbass.gif"]Wiring diagram.[/url][/quote] Odd diagram, they have the whoel ctrl plate the wrong way round, with the jack socket where the neck vol pot should be and the neck vol pot where the jack socket should be. I'd go for 0.22uF also with 250k pots and single coil jazz pups

I found a technical post (as they all are on Guitar Nutz) from my old pal, Cynical, but it's a bit above me. [url="http://guitarnuts2.proboards45.com/index.cgi?board=coffee&action=display&thread=3797&page=3#34252"]http://guitarnuts2.proboards45.com/index.c...mp;page=3#34252[/url] If anyone can shed light on his virtual java oscilloscope traces it may be of interest for a bass treble bleed mod. failing that I'm just going to solder in my 100K/0.001uF cap and see what it sounds like.

Having fitted some new pots to my P-bass I find there is a huge amount of treble loss when I turn down the volume. Keeping tone full up anything under 2/3 vol goes muddy as a very muddy place. I know the treble bleed cap in parallel to resistor thing across the vol pot's in and out terminals for guitars (stay with me if I get too technical guys, heh) but never heard of it being fitted or [i]needed[/i] for a bass. The common values I have for a guitar treble bleed are 100k resistor in parallel with a 1 or 2nF cap (0.001 - 0.002uF) Am I likely to need different values for it to be effective for a bass? Anyone ever had to put this mod in a bass to keep some bright edge when playing at low volume?

[quote]Is the effects loop amplified/eq'd whatever after it returns?[/quote] My understanding is the effects send takes the signal from the pre-amp. the effects return feeds back into the power amp.

[url="http://cgi.ebay.co.uk/PEAVEY-BASS-GUITAR-THROUGH-NECK-NATURAL-SWAMP-WOOD_W0QQitemZ130287028611QQcmdZViewItemQQptZUK_Musical_Instruments_Guitars_CV?hash=item130287028611&_trksid=p3286.c0.m14&_trkparms=72%3A1688%7C66%3A2%7C65%3A12%7C39%3A1%7C240%3A1318"]http://cgi.ebay.co.uk/PEAVEY-BASS-GUITAR-T...A1%7C240%3A1318[/url] No idea about the quality of these basses, but it sure looks nice.

[quote name='EBS_freak' post='411983' date='Feb 17 2009, 02:09 PM']PS - the fretboards aren't removed to have the LEDs fitted.[/quote]Aah, err, how do they fix them then? Do they rout from behind into the neck then fill with a skunk stripe?

[quote name='pal1972' post='412019' date='Feb 17 2009, 02:40 PM']why can't they build them here in blighty!!!![/quote] [soapbox]Cos people like me don't want to spend the extra money to pay for British salaries, health schemes, national insurance, pensions, health and safety legislation, environmental control and everything else that is killing the sad remains of the British manufacturing base [/soapbox] Juast got a reply back from marshall: [b]After speaking to one of our engineers they have said that re-soldering the joint could have solved the problem but if you would like to send the cabinet back through the dealer we would be happy to check it over for you to make sure it is working fine. I will pass the e-mail and photos on to the R+D department and Quality Control so the issue will be raised and looked in to[/b].

Do the stomp box manufacturers actually offer recommendations on the best use of their different pedals? ie: before pre-amp or in the effects loop?

They had a phone call from me today plus an email with my pics in it. I'll have to wait till i get home this eve to see if I have a response. This is the big danger of sending out all your manufacturing to countries where labour is cheaper. i wa on a tight budget and this is the downside. Unless Marshall pay closer attention to this sort of thing, it will escalate and damage ther reputation. They have to strive to be competitive though for the market segment they cater for. in an ideal world I'd have enouigh disposable income to buy a top-end handbuilt british boutique amp and cab that only weighs 12 pounds but packs 750W.