DHA

Hi, I am really interested in hearing comments from those of you who checked out my DHA VT5-400-Bass amp at Music Live on Mark's Bassdirect stand. It will be at BassDay for those that missed Music Live. Dave

[quote name='poptart' post='83751' date='Nov 4 2007, 11:14 PM']Nick It was good to meet you - I have just checked out you're profile I think you have some sort of Bass OCD THING GOING ON - how many basses!?!?!?!?! James Pleasure to help out - your playing certainly got some attention over the weekend, keep up the good work. Mark[/quote] Hi Mark, Just wanted to say thanks again for having some of my kit on your stand, most grateful and I look forward to working with you again soon. Sorry I missed most of the BC members yesterday but hope to see some next week at Bassday? regards Dave at DHA

[quote name='DHA' post='79943' date='Oct 26 2007, 07:31 PM']Hi all, Looks like Mark at Bass Direct will have some my pedals on his stand at Music Live. Also if I can finish it in time the first VT5-400-Bass amp will be there. Many thanks to Mark for his kind offer. I will be there on the Friday and maybe the Sunday as well and it would be great to meet my customers and thank them for their support. Dave[/quote] Just to confirm that the VT5-400-Bass is on the bassdirect stand if anyone wants a go. There are bass pedals on there as well, plus Vanquish guitars/e-basses have other pedals. I will be there again tomorrow if anyone wants a chat. Dave

[quote name='Lorne' post='82415' date='Nov 1 2007, 06:00 PM']Ok,I have 2 vintage B.C.Rich Koa and Maple neck thru basses,a 1985 Bich Supreme 8 string and a 1979 Bich 8 string Whilst the 1985 sounds beautiful,the 1979 sounds completely sh*t,very weak in the bass department All the wires are in the correct places on the bass,so I thought perhaps the Varitone circuit had died,so I got another NEW circuit and installed it,the bass seems Deeper sounding in the out of phase position,which it obviousley shouldn't,but it is still a LOT weaker sounding than the '85 Could it be possible that the Original 1979 DiMarzio pick ups have just had it?,and it needs a new set?,I am contemplating buyin a new complete Bich circuit and 2 pairs of DiMarzio Split P's I can;t test the ohmage of the pick ups as I broke my Draper multimeter [/quote] Very hard to say what the problem might be without being there with a meter. But, to answer your question pick ups do change with age but normally in a good way. My guess is that there is another problem other problem other than aging pickups. Also, did they change overnight? If so it's not aging but something gone wrong. Best get it checked by a techie with the right kit. Dave

[quote name='mybass' post='81427' date='Oct 30 2007, 07:16 PM']I have an Aguilar DB680 pre-amp. It hasn't really been used much and is in storage at home but I thought it best to plug it in every so often. As a note tailed off, there was a very slight and decreasing with the signal "hiss" type noise. I would guess it is the output valve? Can you shed any light on this please. cheers, Pete[/quote] Hi Pete, I don't think it will have an output valve being a pre-amp. I expect it's more likely to be a setting thing, try turning the levels down and see if it's still there. Could be you are overloading your amp with the output level being set to high? Dave

[quote name='andyonbass' post='80319' date='Oct 28 2007, 09:27 AM']Heres one for Dave - I noticed during a gig last night that my VT-1 was causing some high pitched squealing and the on/off switch was causing a loud "pop" when operated. Obviously in mid gig its impossible to experiment to find the cause so I switched it to bypass and finished the gig with no problems. It worked fine for the first set and became apparent as I switched it on after the break. I'm using my ACG bass into the pedal , into my Markbass LM2 head and Eden Nemesis 1x15 cab. No other effects used. I havent had chance to have a look at it yet this morning, I just wondered if you had any thoughts ? Cheers Andy[/quote] Hi Andy, Sounds like the external switchmode power supply has a problem. Switchmode power supplies sometimes don't like being switched on without a load so I expect the power connector may have got disconnected for a moment during the gig, this may have been the thump you heard. Sometimes when they are reconnected they run at the wrong frequency which is what you hear as normally they run at frequency outside of our hearing range. So, it's best to plug the pedal into the power supply first and then plug it into the mains. One funny thing is that once a power supply starts doing this you have to leave it unplugged from the mains for 10mins before it recovers. I expect it will be fine today, if not then it could be the supply is duff. Dave

[quote name='Sugden' post='79561' date='Oct 25 2007, 09:33 PM']I'm pretty sure Dave has replied somewhere else that he isn't going anymore. But Im not certain and I'm sur ehe will correct me if I'm wrong.[/quote] Hi all, Looks like Mark at Bass Direct will have some my pedals on his stand at Music Live. Also if I can finish it in time the first VT5-400-Bass amp will be there. Many thanks to Mark for his kind offer. I will be there on the Friday and maybe the Sunday as well and it would be great to meet my customers and thank them for their support. Dave

[quote name='philbillbass' post='79715' date='Oct 26 2007, 11:07 AM']yeah it is but what stevebasshead was saying about if i turn the bass treble and mid controls all the way down, wel it has the same volume on mine[/quote] It should be a lot lower level and very weak and thin with the tone controls all turned to zero? But the circuit I use will not cut the level completely, as I said it's based on the fender bassman circuit but is not a copy. There is a tone circuit by-pass switch which will mean that controls have no effect at all when in by-pass and there will be a big boost in level, did you try that? Dave

[quote name='philbillbass' post='79706' date='Oct 26 2007, 10:46 AM']yeah the only reason i hav the 1>2 so low is that then i dont get a big increase in volume wen i step on the 1+2 thats all[/quote] I understand. What about the colour switch, is that off (centre position)? Dave

[quote name='philbillbass' post='79283' date='Oct 25 2007, 10:53 AM']i hav a DHA VT2 dual custom bass : i was just wondering does anyone hav any good settings that wil help me to be heard more, as i find that with this on it tends to lose me in the mix as in our band we hav to guitarists to battle with. also in which position is the clipping off (so that it is just the valve's doing their work)? thanks[/quote] Hi, Your 1>2 drive level is set very low? This control sets the amount of overdrive there is as valve 1 drives valve 2. Try turning the level down and 1>2 up, might help. The comments on the scooped mids are good as this will lose the frequencies needed to battle with the guitars. Clip switch is centre off. Let us know how you get on. Dave

I have sold a few things to Jim and I could not ask for a better person to deal with. Dave at DHA

[quote name='Alpha-Dave' post='75626' date='Oct 17 2007, 03:47 PM']Hi Sugden, That looks nice I suppose, but to be honest it's not really my thing, what with having a VT-twin and valve compressor already in my rig ... ... which is why my VT?-400 will just have the basic by-passable tone controls, the valve power amp and the 400 watt output. Hopefully it'll be ready for Dave to bring to Bassday so we don't have to pay shipping. [/quote] It will be a VT2-400-Bass as it's just an output stage and one driver valve. But add in your VT2-Twin and VT1 compressor and you are back up to 5 valves. Dave

[quote name='Sugden' post='75117' date='Oct 16 2007, 04:17 PM']Loving the front dave thanks alot exactly what I was after. I'll have endless hours playing with all the configurations of controls. Im pretty sure I know what all the other controls do except what does the colour section do? Cheers Sug[/quote] Hi Sug, The colour control is a switch pot so it can be off or it switches in a negative feedback path via a pair of clipping diodes. This increases the gain distortion and compression and the amount is controlled with the pot. It's best heard when the gain on the pre-amp is set quite high. There is a drop in output level but lots of increase in distortion, compression and sustain. Colour is fitted on some of the pedals. Dave

[quote name='OldGit' post='74812' date='Oct 15 2007, 09:45 PM']Great tips thanks[/quote] Glad to see that no one suggested the 100W solder guns. They are great for some jobs but never get them near your pick-ups as they can de-magnetise them, end of pick-up. Dave

[quote name='BigRedX' post='74740' date='Oct 15 2007, 07:24 PM']Dave - will you have one of these amps with you a Music Live? I'd very much like to try one out.[/quote] Sorry, we are not going to Music live. Maybe next year. Dave

[quote name='TheBrokenDoor' post='74666' date='Oct 15 2007, 04:53 PM']Hey dAn I'd love to hear the comp and maybe one of those overdrivey gizmos, but since I'm now based in Wigan (Aaaaaargh, get me out of here!!!!) players with gear are a bit thin on the ground!! I still reckon my P is more precise than yours!!! DaN[/quote] We will have a stand at BassDay in Manchester. All the DHA pedals will there for people to try as well as the new VT5-400-Bass amp. Not that far from Wigan. Dave

Latest..... [attachment=2884:PICT0007.JPG] The paint job is a custom one as requested by Sug. The final production models will be silkscreened and have an input and output LED VU meter, all the other features will be the same. There will be a blue backlight showing one of the five valves via the vents. The footswitch controls the compressor and Fx blender off and on as well as the Tuner mute. The colour of the LEDs matches the knobs which are different for different functions, i.e. pre-amp is red, blender yellow, etc. Two of these are still available at the lower cost to BC members. Dave

[quote name='rodl2005' post='73152' date='Oct 12 2007, 06:59 AM']I dunno what my valve "guru" tech did to measure my old amp, But it was definately RMS he informed me of. Definately not "peak". Re the valve to "pump up" the output... I read this in a thread on Talkbass- I think it was the "show yr Fenders" thread. there they talk re how Fender-with the 400PS- got a valve amp with 6 x 6550's to put out 435w RMS!!!!!!!!!!! I've not seen or heard one 'live'-just in the pics on TB. But it sounds like it was a "MOTHER" of an amp! ps. thanx for yr description & thought re the Peavey's power![/quote] I did some checking on 6550s and they are a very powerful valve and it's just possible to get the 435W but that is running the plate current and voltage at max. The Fender must pop valves like there is no tomorrow! The 6 EL34s in your old amp just broke the laws of nature as their plates are rated at 25W max each. What with the transformer losses I don't see were 170W comes from. If he measured the mean then 170W is correct as this is 120W rms which is about right. Dave

[quote name='rodl2005' post='71422' date='Oct 9 2007, 07:59 AM']I must be missing summink too@@@ I had a 6 EL34 amp (sure it was a 1975 baby) & it put out about 170w when we tested it! Do PV do what Fender did yrs ago w/ the 400PS & stick a valve in another section to "pump it up more" ?!?!?!?!????? The Fender 400PS did 435w & had 6x 6550's-normally about 300w. I dunno, but would like to ! [/quote] It's to do with what you mean by watts? Watts is not an audio measurement, dBm is. But, because we don't think in dBm amp manfactures state the wattage of the output stage as a gauge. How loud it is depends on how much current you can put into the speaker. I(current) squared x R(resistance) = W(watts). My point was that there is a max each valves plate can take before it burns out and the figures don't stack up if you take the huge losses in the output transformer and speakers into account. How did you test the amp to get 170w or 300w? If you measured the current into the speakers with a meter this would account for it as the meter will not read rms but mean so your reading will be higher. This is what manufactures state when they say "music" or "peak" power, trust me it's rms that counts. Using a valve to pump it up more will not help get more volume as there is a maxium each valve will get to however hard you drive it. All this will do is overdrive the output stage which will then distort, sounds good but its not louder. But, I think I have worked out what the Peavey VB-3 is doing since my comment. It's very clever if I am right. I believe they are running the output valves in switchmode class D. This way, just like solid state versions of class D you can get a lot more power than the output devices can deliver if running in other modes, class AB mainly. The mains transformer will still be very big but the output transformer will be much smaller. In Class A the output stage is on all the time so the current drawn is the same at full or at no audio out. In Class AB each half of the output stage is on half the time and current drawn changes with output level. In Class D the output stage is switched off and on at a frequency higher than the audio with a duty cycle than means that the current drawn is only a fraction of class A or AB. This means a smaller transformer. Saying that, this is much easier to do with MOSFETs that's why all class D amps are solid state. There will be some very big technical issues to get around using valves such as the MOSFETS will be switching at 40-50V and the valves at 450-500V. Suppressing those switching spikes will be fun. Or, I have put 2 and 2 together and made 5 and they are just using clever marketing. Dave

Hi all, I have not confirmed if we are going to Music Live at the NEC, 2-4th Nov or not. The costs kept mounting up as soon as we said we would go and in the end before I signed the contract it just didn't seem worth it. But, a few of you have asked if we will be there so you can try out the new amps and pedals. So, how many would make it to our stand if we went? If we know in advance that it's going to be busy then it's much more likely we will go. We will be at Bassday in Manchester the following week. Dave at DHA.

[quote name='Stuart Clayton' post='69567' date='Oct 4 2007, 04:47 PM']Hi all, Thought I'd chip in an add a pic of my pedal board, which looks like this: Pedals as following, in this order of signal chain: Ernie Ball Volume Pedal Korg DT-2 Tuner MXR MicroAmp DigiTech DD-3 Digital Delay DHA Distortion DOD Stereo Phaser EBS Chorus Boss SYB-3 Synth Ashdown Envelope Filter DigiTech Whammy Pedal I power most of this using the Dunlop 9V brick, and it lives on a Pedaltrain board. This is what I take on tour with Carl Palmer, and believe me, it all gets used frequently! Stu[/quote] Hi Stu, Nice to see you posting and glad the DHA is on the board. Stu's pedal is a custom DHA VT1 that was made for him to provide a tone required for his work with Carl. It's based on a VT1-MK3-Bass and I hope we got near the tone you where looking for? When is the review coming out? Dave

[quote name='Sugden' post='67692' date='Sep 30 2007, 03:23 PM']Thats a pretty serious looking transformer. Looks like some serious hours gone in there. If i knew what I was looking at Im sure Id be saying fantastic work. Theres some lovely looking 3 teir circuit boards.[/quote] I have to add the components to the 3 teir circuit boards, but they are the compressor, blender, pre-amp and driver.

[quote name='Rich' post='67547' date='Sep 30 2007, 12:23 AM']Watching this with keen interest. Perfect. All it needs is a rackmount kit. [/quote] Build update - note the EL90 power valve next to the output transformer. There is only one pre-amp valve fitted on this pic, 3 more to add. The 400W UcD module is on the back panel, the big black round thing is the transformer for it. [attachment=2541:PICT0035.JPG]

[quote name='alexclaber' post='66399' date='Sep 27 2007, 01:32 PM']The forthcoming Peavey VB-3 uses an SMPS to get the weight of a 300W valve head down to about 30lbs. Alex[/quote] I still don't understand how they get 300W from only 6 EL34s, I think they mean peak and not rms. So I would say its more likely to be 150-160W rms. Or am I missing something

[quote name='Sugden' post='66697' date='Sep 28 2007, 12:37 AM']Hey dave thanks for the pics looks like its coming along swiftly. Going to be a nice full box by the end of things.[/quote] Hi Sug, The 400W amp just arrived, so that's all the bits here now. I see a weekend of drilling and metal bashing coming on. dave