DHA

[quote name='warwickhunt' post='180973' date='Apr 20 2008, 12:26 PM']Hi Dave I realise that this isn't one of your amps (doesn't even contain a valve ) but wondered if you could give me (or my Sparkie mate to be specific) any pointers! I have just taken a Gallien Krueger 800rb in part ex. It has a degree of distortion (buzz/fuzz particularly as the note decays but heard pretty much all of the time) which isn't attenuated by reducing the input gain, depressing the -10 db pad, or using basses with lower output. I've also tried plugging into either of the pair of 300watt outputs and the separate 100 watt output, still the same. I'm aware that each poorly amp could be so for a multitude of reasons but is there a particular area you'd zone in on to check first i.e. output capacitors, some aspect of the preamp, transistors... I'm trying to source the schematic but my mate is prepared to just go through the amp checking tolerances on whatever he can but is there a common failing on solid state amps or a first port of call for distortion problems? Really appreciate any input. Cheers John[/quote] Hi John, it will be a duff component or two, but which one is impossible to tell without a scope and a diagram. Sorry, I can't help much. Dave

[quote name='WarPig' post='177189' date='Apr 15 2008, 05:37 PM']Make it 2 [/quote] Thanks

[quote name='dannybuoy' post='174459' date='Apr 11 2008, 12:14 PM']You should put these on ebay and your website and make an announcement over at Talkbass if you want to shift more of them...[/quote] Also, I won't be sending kits to the US as we have a rep there now and it's up to him so I won't be making this offer on talkbass. Dave

[quote name='dannybuoy' post='174459' date='Apr 11 2008, 12:14 PM']You should put these on ebay and your website and make an announcement over at Talkbass if you want to shift more of them...[/quote] They might go on ebay one day. I have less time now due to other comments so the kits are just a way of keeping things ticking over until I make other arrangements. So not really wanting to sell lots. Dave

[quote name='finnbass' post='173533' date='Apr 9 2008, 11:25 PM']Oh, I wouldn't say that [/quote] Nice one Steve. dave

[quote name='WarPig' post='171975' date='Apr 8 2008, 01:17 AM']Will you be offering kits for any other pedals in the near future?[/quote] It depends on how this one goes. At present I have sold zero, so not looking good. Dave

[quote name='danlea' post='171501' date='Apr 7 2008, 02:53 PM']Hey there, I bought I a VT2 Dual Bass pedal around Christmas '06 and never really got back to you on my thoughts, so that's the first part of this post. When used in full overdrive mode (I mean cranked with both valves to the point just shy of valve squeal) it really does give a fantastic sound - something I'm using on a track we're currently mixing, in chorsuses and for bass feedback at the end (I'll post a link once it's finished). I have to say I don't find any use for the single valve setting due to the great difference in output levels. I'm running it into a GP12 SMX amp (valve/ss blend input stage) so I don't want to overdrive the this preamp, hence the output level is set pretty low. Unfortunately, this means the single valve setting on the pedal is too quiet. For me it would be nice to have separate output levels for each of the settings so I could have both options, but as it happens I'm happy with using it purely in the dual valve mode. The other issue I have with the unit is that there seems to be some capacitive coupling (or some other form of electrical connection) when in true bypass (noticeable when the valves are cranked, as they are for me). I've gotten around this by putting it by itself in a true bypass effects loop (which I use for its tuner mute anyway), but I thought I'd let you know about it. Now, I've gotten this silly idea of whacking a piezo bridge onto my passive (Fender Jap) precision bass. Now, my precision pickup must remain passive, but naturally the piezoelectric transducer would need it's own onboard preamp. I'd probably send the two separate signals via a stereo cable and split them to two mono connections close to my rig. Now I'd like a valve on the end of the passive connection, so would Bob the Blender be a decent option for mixing the passive and active connections? I ask because I'm not entirely sure how the signals are blended in context of the valve (I don't think I'd want them being mixed passively). Dan.[/quote] Hi Dan, Using Bob as a mixer should work but you will have to match the signal levels. Dave

[quote name='umph' post='168964' date='Apr 3 2008, 10:30 AM']aye i agree specially if it comes with all the manual and a trouble shooting guide![/quote] We are open for business on this if anyone is interested. so two options 1. VT1-Bass - i/p pad, gain, level, colour switch, bright switch, boost switch. True by-pass with back light LED and effect on LED. - all bits plus instructions etc. plain box which will need drilling and painting - £65 plus £4.25 P&P 2. As above but with pre-drilled box. - £70 + £4.25 P&P. PayPal payments can be made at [email protected] but just write on the notes what it's for. Dave

[quote name='Alfie' post='167482' date='Apr 1 2008, 10:34 AM']This sounds like a pretty good deal and I appreciate your efforts to keep your fantastic product available to those on a smaller budget. I was wondering whether you had any tips about painting the encosure? How do you achieve such a thick and hard finish? Is it just a case of leaving the boxes to dry properly for a long time, or are there any particularly strong paints or varnishes that you would recommend? From the smell of it I would say at was some kind of enamel paint.[/quote] Hammerite smooth Dave

[quote name='Metal-Mariachi' post='167329' date='Mar 31 2008, 11:41 PM']I’d be very interested in buying one. I also think the price is reasonable. Funny I was toying with the idea of sending you an enclosure with my artwork/paint job to build one in. Let us know when they will be available MM[/quote] They are available now. I just need to write the instructions. Dave

[quote name='metaltime' post='167291' date='Mar 31 2008, 10:44 PM']How hard do you think it would be to put together Dave? Also being able to drill your own box would be cool i think could arrange it however you want then.[/quote] I will be making the instructions as simple as possible with lot's of photos as I assemble one. There is a PCB to load and solder which is just a case of putting the correct components in the right hole, the components and the PCB are marked up. There is the valve socket to wire and about another 20 wires to connect which will be colour coded. It takes us about an hour to wire one so someone new to it and being careful should take about 2-3 hours I would guess. I will also write about a way to test it and fault find if there is a problem. If anyone really can't get one going then we will take it back for repair. Dave

[quote name='Alfie' post='167000' date='Mar 31 2008, 04:48 PM']I would be more interested in the VT1 Std[/quote] Okay, How about this..... The difference in cost of parts between a Std and Mk3 is about £5 it's the work in putting them together and it was hoped the Std would be a volume product. Anyway I am going to offer a new version which will be a Std plus a colour switch so it does not complete with what we make. For your info there is over £40 in parts in a Std and that's buying in bulk. It will be £65 with an undrilled box and £70 with a drilled box. I think the price is fair considering it's taken several years to develop the design and there is still work to do kitting the kits, posting, etc. I am doing this to keep DHA ticking over as I have become very busy in my main (real) job so I find I don't have the time anymore. What time I have got spare will mainly go on the VTX amps. Please PM me if anyone wants one and I will send invoices and get the camera out for the instruction manual! Dave

Hi all, I am thinking of providing a VT1-MK3-bass pedal kit and wanted to see if there is a market before I offer it. You would get a PCB, all the components, box, knobs, screws, nuts, wire and instructions. You would need a soldering iron, solder and a few tools to make it. The making would include drilling and painting the box. Would be around £70+P&P. what do you think? dave

[quote name='razzthekid88' post='166325' date='Mar 30 2008, 02:20 PM']My SVT only has a 2 or 4 ohm impedance selector. Was just wondering if it'll mess up the tubes if I use a single 8 ohm cab? Or will it be okay using it with the SVT at 4 ohms? If not then is there anyway to make using an 8ohm cab safer? Cheers[/quote] You will run the risk of burning out not only the valves but also the output transformer if you don't match the impedance. You must use a matching cab with a valve amp. Dave

[quote name='Vasquez Rich' post='166134' date='Mar 29 2008, 09:52 PM']Dave, Thanks for that. I re soldered the capacitor connection as it was on a direct run on the circuit board to the point at which I was getting the DC on the speaker out terminal. I rebuilt everything up and it seems to be working, there is no voltage at the speaker terminal and the speaker itself sounds normal with just the normal hissing when it's turned up. I take your point about having probably repaired a result of a fault and not the fault itself.. I will test the thing out properly in the next few days. If I keep it it will be my 3rd best amp in anycase. If the fault returns then it will be a dead giveaway with the loud buzzing. Thanks again, Richard[/quote] Hi Richard, sounds like you got a good result. Might just have been the connection to the cap that caused the problem. Dave

[quote name='Vasquez Rich' post='165981' date='Mar 29 2008, 05:45 PM']I've just stripped the power stage out and one of the large electrolytic capacitors (4700 microfarad, 100V) has one of it's connections loose. In addition it looks like something has got it hot enough to melt the solder connection leaving the metal strip loose through the circuit board, there are some small black "burn" marks on the underside of the circuit board, but only around where the solder should have been. I can obviously resolder this back, but was wondering if the connection has got hot enough then is it likely that the capacitor has blown? What could get that connection so hot? Richard[/quote] Looks like some DC has got on to the speaker connection. This will be due to a power supply fault and the current drawn will have caused the burning on the board. I expect there was a low ohm resistor between the pre-amp and power section grounds as this stops earth loops. But when there is a problem this resistor will overheat. Beware - this sort of fault will burn out speakers if the DC flowing gets to large. I would say that there is a fault in the power section and the other damage you are seeing is an effect of this and maybe not the cause. This needs to be looked at by someone that has the diagrams and the knowhow to fix it IMHO. Dave

[quote name='stevie' post='165142' date='Mar 28 2008, 11:58 AM']Anyone familiar with the old OHM GA125 bass combo? I recently acquired one that was crackling. I resoldered a few connections on the PCB and managed to fix it. Resoldering and replacing components is about my limit, I'm afraid. The amp seems to be working now but I am concerned that two of the wirewound resistors on the preamp board are getting very hot. The amp is split into a preamp section (front) and a power amp section (back) with an umbilical cord between them which seems to carry the power from the power supply (on the power amp board) to the preamp. The two resistors are the first components in the preamp circuit at this point. The original resistors were 470 ohm, 5W wirewound, but as they were visibly burning the board, I changed them to 10W wirewound and spaced them away from the board. However, even these ones are still getting very hot. By hot, I mean you can touch them but you can't keep your finger on them for more than a fraction of a second. Is this normal? Second question for the experts. I have taken the amp out of the combo and installed it in an amp sleeve. The graphic section of the preamp is now closer to the mains transformer and is picking up losts of hum. Moving the preamp away from the transformer reduces the hum. So, I've turned the preamp round 180 degrees so that the input section is next to the transformer and the hum has gone (the power amp is now upside down in the sleeve, if you follow me). I'm not very happy about the power amp being upside down. I would have thought that the input section of the preamp would be more susceptible to hum than the graphic section. Any ideas what I should be looking for here, or is this normal? Finally, the compressor operates very oddly and degrades the sound of the bass. It's basically unusable. Is this also par for the course? Taking the amp to a repairman would cost more than the unit is worth. Any help in saving it from the landfill would be much appreciated. Stephen[/quote] Good move upgrading the resistors to 10W, I would say that if you can touch them at all then all is well. The tuned circuits in the graphic section are most likely picking up the 50Hz. You could try adding an earthed metal plate between the pre-amp and power section as this should block the 50Hz signal and hence remove the hum. No idea about the compressor. Dave

[quote name='richardd' post='161428' date='Mar 21 2008, 02:23 PM']Hi Everyone I have a G&K 200RB head whitch some times does not emit any sound even though the start up lights do the usual red to green sequence tried new speaker and bass leads , when it does fire up it seems to struggle for a few seconds then all is well, once it is working it does not show any unusual symptoms, any ideas Regards Rich[/quote] Sounds like a power supply problem but impossible to work out for sure via emails. sorry I can't be more help. Dave

I am sorry to have to do this but the prices of all our products will be going up soon. I will be changing the ebay prices over the weekend and the website will change soon after. Sales have been very good for a while now and the amps are starting to move as well, but it being a part time job for both me and Jim means we have been slow getting stuff out the door, sorry to those waiting for amps and pedals. So, we are going to change the way we operate and outsoucing some of the tasks is one of the solutions this is a more costly thing to do and the prices have to reflect this. I wanted to let members of this forum know in advance just in case some of you were just about to buy. I will also do my best to help with the price if any of you had plans to buy in the near future. regards Dave

[quote name='Perry' post='160276' date='Mar 19 2008, 03:11 PM']I have a Hartke A100 combo all works well. The only querry I have is that there is a Thud sound when I turn the amp off or on even with the volume turned right down. It's enough to move the speaker about 5mm. Is this OK?[/quote] Nothing to worry about and most amps do this. Dave

[quote name='clauster' post='158362' date='Mar 16 2008, 11:57 AM']Dave, any progress with the rack mount version?[/quote] I had kind of gone off the idea but I could relook at it if anybody wants one. Dave

[quote name='sk8' post='152849' date='Mar 7 2008, 07:52 AM']Dave Will the compressor add warm up a solid state amp as well as providing compression?[/quote] a bit but not as much as any of the overdrives. Dave

[quote name='jwbassman' post='151504' date='Mar 5 2008, 08:24 AM']Hi Dave What Cabs would you suggest matching to your amps? Only asking because recently read a thread saying that Epi cabs are not well matched with Valve amps (I currently have a Epi UL112) so don't know if that would work with your amp, I'm guessing because you're using a D Class SS at the end it would be ok . Also what Ohms should the cabs be? Depending upon how things go in the next few months I could be interested a 400w version?[/quote] As the high volume output is solid state then there won't be any issues with any cabs. All the versons produce max output at 4ohm and have 2 parallel speakon connectors. Dave

[quote name='Mr. Foxen' post='151362' date='Mar 4 2008, 09:47 PM']I've just been given a mullard ECC81, if I were to put that in the left position of my VT2, would it give me one channel of warmer, without the grrrr, and the second channel for the overdrive distortion? Or will it make everything go wrong? I'm trying to learn valves through experimentation.[/quote] It will work in both sides and well worth just playing around with. have fun. Dave

[quote name='wazz' post='150851' date='Mar 4 2008, 09:13 AM']Superb. Hows the build coming along? Warren[/quote] The new boards are due in any day and Jim is shoe horning the 700W module and power supply into the 2U rack. Dave