Chienmortbb

[quote name='alexclaber' timestamp='1434364976' post='2798877'] One handle. About 100lbs. And 50 years old. [/quote]Have you ever got a decent sound out of it, Sold mine and bought an AC30 treble boost. Wish I still had it.

Health problems have prevented much progress recently and so a lot of thinking has gone on and a slight layout change. I have added more heatsink. I have attached a picture of the original layout and one with the extra heatsink. The layout adds a second heatsink and requires that the two preamp regulators move. I added the Ezra heatsink as I want to be able to use the full power of the amp and thermal management is the liting factor even with Class D, Now everyone told you the Class D amps run cool but the truth is they run cooler but some heat is dissipated. Compare a Class D Amp to a Class A/B. Most solid state amps used to be class A/B and the highest possible efficiency for Class A/B is approx 70%. That means 30% of input power is wasted as heat. So a 100W amp would have approx 43 watts waste as heat. In contrast a good class D amp would be over 90% efficient so our 100 watt amp wastes only 11 watts. In effect a 400 Watt Class D amp needs the same heatsink as a 100 watt Solid State amp. My heatsink a were designed for a fan cooled 240 watt amp and although that looks like overkill, I am not using a fan although there is room for one if needed. Despite the apparent overkill on the heat sinking, the fins on all three heat sinks are lie horizontally, the least efficient way to cool an amplifier. I hope that there is enough convection and radiated to keep the amp cool but it might need fan assutance to run at full power.

No the marketing dept doubled the RMS (average) output power. The mibass uses an Anaview power module rated at 320W. From more that is at 1% distortion. At 10% it will output aprox 420 watts. Of course those figure are at 4 ohms do you cAn halve them for 8 ohms, However how loud is sounds depends on the bass, preamp design and speakers.

[quote name='aledeville' timestamp='1432409389' post='2781258'] The Synq's are really good! Very quick and precise. I had the Crest 8200 before the Synq 3k6 and this is some difference for sure. For normal use the 1k0 is fine and delivers very much for not that much money. The 2k2 is really tough, but I was able to get the 3k6 for the price of the 2k2 (they were not in stock). So I got that going... which is fine with me Nothing can compete with these amps without making huge limitations in some points. These things are light, loud, precise and comparatively reasonably priced. [/quote]I do not know the synq amps but 3600 watts in 1U is difficult. If you tske the best Clasd D amp it will be approx 93% efficient and a SMPS will be around 90%. So your amp will be generating approx 700 watts of heat Even with multiple fans and the biggest heat sink it would be hard to keep that cool,

[quote name='dincz' timestamp='1421637632' post='2663517'] I've used a Behringer EPQ900. My only complaint is the noisy fans. [/quote]fans can be replaced although good quiet ones can be expensive.

If the control is anti-log (UK) or reverse log/ reverse audio them it is likely that the volume control is a baxandal volume control. This is where the potentiometer controls the gain of the preamp rather than the preamp boosting the signal then a pot attenuating it, This technique was used in the old HH amps. It has several advantages but none you could hear and I believe Warwick were using "marketing speak" when they described it.

[quote name='stevie' timestamp='1359754895' post='1960034'] Thin-wall cabinets ring like crazy. Plastic cabs are useless for bass. Plus a good PA cab is voiced a lot flatter than a bass cab. This is not a good idea. [/quote]you are correct in that most of those plastic PA cabs very poor at low frequencies due to the thickness of the composite used. However my Ramsa PA cabs and Subs have 15mm thick walls and external ribing and are superb, they are small but not tiny and light but not ultra light. I believe that some of Duke Le Juene's ( or could have been a Greenboy) designs were available in a composite version and they too had a good reputation. The material is fine it is the implementation that matters.

[quote name='Dad3353' timestamp='1431257751' post='2769257'] Your guitarist has a point, up to a point, though. The higher the signal, the less gain needed afterwards; any added gain will increase extraneous noise, as well as the signal. Ideally, the signal sent should be adjusted to be the optimum required, neither too low nor too high. Obviously impractical most of the time, so it could be held to be best to send as much as possible (ie: full up...) unless that's too much, in which case turn it down until the overload is gone. In practical terms, I'd leave it full up unless asked to reduce; that's the 'fail-safe' option. The same applies to the instrument. If the bass is turned down, the increased 'gain' in the amp will bring up the level, but bring with it increased noise. The higher level from the instrument, the better, from that point of view. Just sayin'. [/quote]The higher the signal the better. A good desk will have mic and line inputs and most DIs on amps, even at full output, will be well below the max level for a line input. The headroom on a decent mixer preamp would be 20-30dB and that is massive. Most Amps take the cheap way out and output around -10dB so it makes no sense to reduce that level in any way as it reduces the signal to noise ratio on that chsnnel, If the mixer or sound man can't sort it out, you need a new mixer/sound man.

[quote name='stevie' timestamp='1430910860' post='2765784'] That's a perfect design, IMO. Rod is one of the few people posting on professional audio on the internet whose advice is solid. I'd prefer the second order crossover option for use with a midrange driver. Apart from that - bang-on. There are lots of good ideas in that article. I particularly liked his comments on valve amplifiers. [/quote]Stevie Rod has some good articles on valves and valve amps and links to some good resources. They are all worth a read. I think this is an excellent project. Has given me a few ideas although I am trying to resist feature creep, Now back to my project.

Maybe it shows that us Darzet Dumplings know that all that shiny yellow stuff may not be gold.

I will probably my regret asking this but by why would anyone want a valve front end these days? If there is any magic in valves it comes from the output transformer and owner supply not the preamp.

It's been a while since I posted on here and many things have happened in my personal life. So apologies again for the delays. My computer crashed during a back up to my USB drive, It took out both the computer and the USB drive. I have been struggling for the last week trying to get a working computer. I lost all of the files I had created for the Amp, specifically front panel designs and block diagrams. In addition the boss is in hospital so it's not been a good few weeks for me. As a result little progress has been made with the amp. In the meantime, Rod Elliot on his ESP pages has posted a bells and whistles design for a bass amp. Part one is here: http://www.sound.westhost.com/project152-1.htm I would be interested in your comments.

That is almost certainly a choke from a crossover, if it has come adrift, then you should investigate why it came off before trying to repair it.

MAJ is really the only place for spares for HH but the cosmetic ones like the knobs, side panels and knurled nuts are all now finished. I did buy my new front panel from MAJ though.

[quote name='chris_b' timestamp='1427704914' post='2733118'] Merton is selling his Barefaced SC g3 cabs for the same reason. I wonder how many people are moving about on your (and his) side of the stage? How would your rig get knocked over? When I set up there's just me and access to the drum kit on my side. Also, how loud do you play? My bands are pretty loud and I had no trouble hearing my 2 112 cabs and that rig didn't even come up to my waist. I found no need to vertically stack my 112 cabs. Back in the day, we used to stack 2 412 cabs and a valve amp on some very iffy stages and I've never seen a stack come close to falling over. [/quote]what is the reason that Merton is selling his cabs?

[quote name='chris_b' timestamp='1427704914' post='2733118'] Merton is selling his Barefaced SC g3 cabs for the same reason. I wonder how many people are moving about on your (and his) side of the stage? How would your rig get knocked over? When I set up there's just me and access to the drum kit on my side. Also, how loud do you play? My bands are pretty loud and I had no trouble hearing my 2 112 cabs and that rig didn't even come up to my waist. I found no need to vertically stack my 112 cabs. Back in the day, we used to stack 2 412 cabs and a valve amp on some very iffy stages and I've never seen a stack come close to falling over. [/quote]what is the reason that Merton is selling his cabs?

I have a VS Bassamp. It is working but there are a number of issues ( all cosmetic ) with these amps. Firstly the knobs. These were chrome but dud not stand up to heavy use. I have the original knobs but am still searching for an economical way to re-chrome them. The Perspex front panel can crack. Mine has but I have a new one to fit. Some lose their large knurled thumb screws that hold on the side panel/handles and they are again possible to replace. Two of mine are missing but II also have an HH Bassamp 100 and wil move two from that to the VS. The side panel/handle can crack. I have had three HH amps and none of these have cracked although being 40+ years old there. are some "road wear" marks. If the power amp many modern power amo module can be fitted, even some class D. A class D amp will increase the power but do nothing for the weight. Clearly mine needs a little work done but as I am now building me own amp, I might be willing to sell, make he an offer but there will be a short wait while I refurbish it. I am not specifically putting this up for sale but It would be nice for it to find a good home.

I have installed a new firewall to protect from all the flames but,,, Try a Behringer XM2000S. They are prefered by BBC engineers for their neutral sound.

That was my feeling StevIe, that there was an encoding problem.

There is a strange sound on that recording. It sounds like an artefact of some kind and seems to follow each note. The basic tone of the amp sounds cleanish but it is hard to be objective with the after note noise. Headphones used - AKG K450 fed from IPhone 3G*, and Kindle Fire HD. One further point. The TH500 uses an ice power 250asx2 power amp. It is capable of 500W into 4 or 8 ohms depending how Aguilar have configured it. There are two power amps and if connected as two Single Ended amps (rather than a bridged amp) one feeding each speaker socket, the max power into 8 ohms from each outlet would be 125W. Not perhaps the power house you would expect if pushing for volume. *Has the best Analogue to Digital converter so the best phone for audio.

With regards to the TH500, any one run out of headroom or find it gets hit if driven moderately or hard. There just does not seem to be enough metal in there to keep a 500W (even a Class D) cool at those power levels.

The designs are early stage Charlie and I am the one that never goes to a blockbuster, and despite everyone's efforts never got Springsteen,so I will not use blue LEDs just because they are en vogue. Might try some purple ones though. It helps having you guys around though to keep me honest.Now where can I buy some HH electroluminescent strip.

Phil, I live in Poole and I would love to meet to checkout the Cabs especially with the amp I am building. Unfortunately I can't get out much due to my wife's illness. Perhaps we could arrange a Somerset/Devon/Dorset get together at the same time around June.

A good point about the jack sockets. I will look at that later and it may also help with the spacing about the knobs.

[quote name='LukeFRC' timestamp='1427064594' post='2725444'] text wise the 3rd one is better- but - keep the type all the same size/ weight and in line across the top. I also know why you've spaced them as you have, and it kinda makes sense but visually in 3d - and also in terms of the ergonomics of the thing I would space the knobs out equally to each other across the top. Colourwise I like the orange one - (but not the type choice for can'd heat) . No mute button? [/quote] Good points. The typeface for the controls will changed to a uniform style and size. The control spacing will be equal too, I just need to play around with the control names a bit as the longer names screw with the spacing. The Can'd Heat' is an abreviation of the place I live and I thought it fun in a Lynyrd Skynyrd kind of way. If I keep it, the font will change. As for the mute switch, you have caught me out. Front panel mute is part of the design but I forgot to include it on the drawings. I like all three colours in different ways and will try the black one first as my laser printer is monochrome. However I can get the red and orange printed at Staples for about £1