Mottlefeeder

I agree with the comments about load and distortion, but most users will never use continous high power, so the larger an amp, the less relevant RMS power becomes. If the ratio of bass peaks to bass average signal is about eight to one [citation needed here], then specifying RMS power will cover you if you want to play a continuous synth or organ bass note, but for any other meaningful bass line you will be paying a lot of money for a high-powered, RMS, 24/7 rated system whose capabilities you will never use. Surely what we need is a measurement that covers both continuous power and higher powers for a defined proportion of the time. For example, 300W RMS 24/7 and 500W RMS for 10 seconds in every minute and 250 W RMS for the remaining 50 seconds. If we specify the right proportions of intermittent and continuous power right then we should be able to ensure that bass amplifiers have enough reserves in their power supplies to provide the heft we crave while not being priced out of our reach. David

It's missing the electrics, but sold as 'missing mechanicals' so it is not clear whether you are getting the bass as pictured, or just two bits of wood. David

It's an area in which I'm weak, so I was interested to watch it. Unfortunately, especially on your second example, I really struggled to hear the undelying bar structure as you played. Can I suggest that after you have demonstrated the note sequence, you play with a metronome or backing track to make it more obvious? David

You can convert a linear pot to a lower value log pot by ptting a resistor between the wiper and one end of the track. A fixed resistor value somewhere between 1/4 and 1/6 of the value of the track will get you fairly close. That suggests that a 100K twin pot could give you a 100K linear and a 20K log pot. Not sure if that helps. David

+1 for Steve Robinson David

Dirty contacts may be the cause of your switch-on click, or alternatively, a faulty output relay could cause that, and the distortion that you are hearing. I've only used Ashdown to repair one of their amps (fried by a faulty generator), so I cannot comment on amp techs in general, but there have been threads on that topic. David

if you don't know its history, it's possible that whatever ambient crap the fan pulled through it has tarnished the Fx socket contacts, and also some of the other switches, so yes you probably need an amp tech, but it may be no worse than cleaning the various contacts in the signal path. This is the type of jack socket fitted to the FX circuit of a Hartke HA4000 This is the state that the contacts were in This is what they looked like after cleaning David

Having seen the block diagram, I suggest starting with a mic cable from the DI out to your mixer. That will check out the whole preamp (post EQ) or just the input stage (pre-EQ) while bypassing the Fx sockets (which might be the problem). David

I may be wrong, but I think headphones are normally fed from the main amp via an attenuator, so: a) using your bass to BD121 to Fx-return would bypass most of the preamp, and b) using bass to BD121 to amp input, and Fx-send to mixer to headphones would bypass the amp Make sure to make all the connections with the power off and the volume controls off to avoid noisy surprises. Siully question, but can't see the answer in your original post - have you tried bass to GK to BF cab without the Behringer, in case it is the faulty item? David

Having got as far as narrowing down the fault to the amp, I'd check the preamp outputs and tuner outputs for distortion. This will tell you whether the fault is in the Amp or the preamp. The former is likely to be much more expensive, but the latter may be as simple as dirty contacts on the FX send and return sockets. David

I use a strap to secure my bass to the side of the speaker cab, or to secure the gigbag to the side of the speaker cab, so I can just slide the bass into it when we stop for a break. It works if you have one tall cab or two stacked cabs. Markbass do/did a purpose made strap for this. David

Thanks Phil. David

I've seen triangular ports in some designs, but never seen any guidance about how to calculate them. Are they calculated as square ports and built in two halves, or is there some correction factor needed to compensate for the extra resistance of the additional wall, and the effect of the cab walls close by? David

I'm not familiar with that amp, but have you considered a 2U rack tray as an alternative. If the amp is open-topped you couldd use the tray upside down. https://www.studiospares.com/ProductDetail.aspx?p=401350 David

Yes, Kala do 5-string models in their solid body range. The scale length is 23.5 inches as against 22 inches for a typical u-bass. Aquila do a 5-string set, but the low B is from their Red series, so it looks a bit odd on a BEAD 4-string, but it works for me. David

You might need to check the speakers used before deciding that. If they use 4 x 32 ohm speakers to give you a 8 ohm cab, you can simply connect your four cabs in parallel. but if they are wiring four 8 ohm speakers in series/parallel, then your separate box connections will be come a bit more complicated, and two 2x10" cabs might be an easier option. David

Is there a problem?

They feel different in that the tensioned string does not have the length beyond the nut, and round the tuning peg, so the string is not as 'elastic' as a conventional bass. Also, with a short body and no horn, a bass strap will hold the bass two frets to the left of a typical bass, which takes time to get used to. If you play on crowded stages, open mic nights or under a small gazebo, having a shorter bass is much easier to work with. David

If you wire the amplifer output to a Jack plug, it will be shorted out momentarily every time you plug it into a socket when both the tip and the sleeve are moving passed the first contact, and possibly also when the Jack plug is unplugged and dangling free. On most occasions, the amp will be off, but one day it won't be, and since it was designed to be permanently connected to a speaker, it probably does not have short circuit protection built in. I had a similar arrangement with a high-powered speaker in a low-powered combo, with the option of using an external higher-powered amp. Setting up in a hurry on a dark stage, I managed to connect the output of one amp to the output of the other. The bigger amp fried the smaller one. I've since redesigned it to make sure it can't happen again. Whatever you do, it has to be idiot proof, so I'd suggest a 10 Amp two way switch with the speaker connected to the switch wiper, and one switch contact connected to the amp and the other to a speakon socket. No risk of shorting either amp, and nice big contacts on the switch and the plug/socket. David

400W @ 1KHz but at lower frequencies it runs out of cone movement well before that. David

Eminence provide speaker design details for most of their speakers, but you have to go to that speaker page to get to them. For your unit they offer this - http://www.eminence.com/pdf/Delta_12A_cab.pdf In a large box, it goes deep, but has limited power handling (2.5 cu ft / 60Hz / 50W). In a smaller box, it handles more power, but does not go as deep (1.35 cu ft / 78Hz / 100W or 0.75 cu ft / 100Hz / 200W). It might work in a monitor wedge, but not very well as a bass guitar speaker. David

Had two gigs yesterday - Left home at about 08:45 with my battery powered gear to get to Wythenshawe to set up bass gear and PA for a 10:00 start. Busked until 16:00 with two half hour breaks. Packed up and got home at 17:10. Loaded in the battery rig and loaded out the mains rig. Left home at about 18:00 heading for a village fair in a field in Weaverham. Set up by 19:30 - pie and chips while the other act was on, then were were on for just over an hour. Packed up while the crowd watched the fireworks - got home about 22:15. Today we started about 10:30, busking in the entrance of a local Tesco Extra. We had two bass players, so we shared the load. Musically, it was mixed - we don't have set lists, so you know most of the songs being covered, until the lead busker decides to try out a new one. For paid gigs like the evening one, we have a smaller pot of songs that we know well, but we still follow whatever the lead busker decides to do next. All the donations and payments go directly to Cancer Research UK. David http://www.loosechangebuskers.org.uk/

I'm no expert, but the style reminds me of early transistor amplifiers, which were about 100W each. It may not be very loud. David

In theory, yes you can, but in practice it would not be a good idea. Jack sockets for speakers are fairly robust, and may cope with 500W, but jacks intended to switch signal inputs tend to be more fragile. A better solution might be to install a double pole two way switch and switch the amplifier output between the internal speaker and a speakon or jack socket. Speakons are designed for that job, many jack sockets are not. David

Harley Benton being built for a German company, and Fender being a US company, could it be that your existing allen keys are imperial and the HB needs a metric one? David