Is there much difference in the Power section of the popular Class D Amps

[fdeck]

JFET 'clone' of a tube Fender or similar line stage?

Close. Ampeg. It has a passive James tone circuit and an active swept mid, so it's nominally flat when the knobs are centered. Of course I wouldn't dare suggest it sounds like an Ampeg, and I'm not even equipped to make that comparison.

 

[Snert]

Close. Ampeg. It has a passive James tone circuit and an active swept mid, so it's nominally flat when the knobs are centered. Of course I wouldn't dare suggest it sounds like an Ampeg, and I'm not even equipped to make that comparison.

I've made similar in the past and I enjoy making circuits with 'air PCBs', a holdover from my early days in electronics of making tube circuits point to point. I still do the latter fairly regularly as I get occasional commissions for tube hifi amps.

 

[radvbass]

Thanks for all the compare and contrast. Super opinions, knowledge and experience. My summary so far is kinda like the 80/20 rule:
If you want 100% of what a vender has to offer in the "designed tone" / feature department, then the pre-amp/amp combo is the way to go. Can't deny this one.

But I'm almost sold the the "power section" may have no more than 20% influance on the final tone. More than we give credit to actually comes from playing style (fingering style, muting, picking, slapping, dynamics...) as well as the upstream instrument and instrument controls.

I'm sold on the Class-D ergonomics. I'm not really wanting to go to the "rack mount" model or feel the A/B has enough influance to overcome the convieniand of the class-d. Ive gone back and forth and I'm trying to avoid it as lugging big gear is something I want to avoid.

At the end of the day, my approach is to package 80%+ of my sound prior to amplification so that I can get similar sound via practice amp, board, small venue, medium venue. I guess I want to "scale" the final output and have a consistent tone.

As I play with different people in different sessions, I sometime like the drive os the sans amp for the classic rock band but the roundness of the Eden Pre for the prog-rock recording session.

I have started my quest in packaging my sound in a small pedel array that I've adapted to a binder size carry case. I'll post some pics in the next day or so. Embedded in the carry case is a pre-amp and some pedals and Trace Elliot Elf amp that works well for most small rehersals.

When I need to fill a bigger room, i patch the last pedal into a bass amp and tune to the room.

I'm settling on: Get a nice relable class D amp with mostly standard features (mute, DI, send loop, aux in, pad) and a basic EQ and make sure it has headroom (typically 700 - 800 watts).
Then play with some pre-amps to dial in tone preferences without expecting the "amp" to have the final killer tone.

If you buy quality used gear right, then then expense to experiment is not too great as long as you are diligent to sell the gear that doesn't have a place. Easier said than done sometimes.

Thanks for making me think and all the great responses

 

[AlexanderB]

Get a nice relable class D amp with mostly standard features (mute, DI, send loop, aux in, pad) and a basic EQ and make sure it has headroom (typically 700 - 800 watts).

This describes the EBS Reidmar 750! Not too many uncolored amps with aux-in at that power level.

 

[Snert]

Not too many uncolored amps with aux-in at that power level.

HB Block 800B has an Aux in and the FX loop return is post EQ etc. I've been told it's an ICEpower 700AS module so it's very clean as these have been used in expensive hifi gear like Wyred4Sound.

 

[AlexanderB]

HB Block 800B has an Aux in and the FX loop return is post EQ etc. I've been told it's an ICEpower 700AS module so it's very clean as these have been used in expensive hifi gear like Wyred4Sound.

Seems very low priced for that ICE 700AS module. Reidmar 750 has more features (of limited use for OP?), and maybe a design, sound quality and robustness aimed at the professional player. But the HB might be a perfectly servicable solution!

 

[Snert]

Seems very low priced for that ICE 700AS module.

It's an older design, so likely cheaper to buy and HB will be buying in bulk. I haven't taken the lid off mine but I've seen it in reviews and it's definitely an ICEPower board. One review translated in an older thread here says it's a 700ASC. IP modules are clean and not adding any signature from the power stage. I can buy the 800B for not much more than a single bare module from some of the suppliers.

Edit: ICEPower logo on the output end of the board.

 

[eeyorebass]

@agedhorse, would the Genzler re/Q drive something like the Baby Sumo? Or is it a pedal more than a pre-amp? In the main GSS Sumo thread, users were saying you need a proper pre-amp signal to get the most of them.

 

[BobKos]

For the OP - I was in a similar quandary recently. I wanted to use my Tech 21 YYZ DI as a preamp without any other EQ or preamp. I researched power amps and ended up with an older Crown 2ch CE1000. It weighs a ton but I didn't care. It was cheap ($50). The 2 channel setup allows me to bi-amp with the YYZ which is really cool. In the process of searching, I was close to buying a Crown XLS-1000 which is a nicer 2 ch 400 WPC amp. You can be very creative with a 2 channel setup and the XLS is class D so it is light and powerful. They are available sub $200 in the used market.

 

[agedhorse]

@agedhorse, would the Genzler re/Q drive something like the Baby Sumo? Or is it a pedal more than a pre-amp? In the main GSS Sumo thread, users were saying you need a proper pre-amp signal to get the most of them.

It depends on the sensitivity of the amp and how hot the bass is. There's 9dB of output gain on the EQ section with the eq engaged, this is plenty for a hotter bass but maybe not enough for say a passive P. The maximum output level is plenty with a 12V or 18V power supply if there's enough gain.

 

[radvbass]

As promised, some pics and description of the pre-rig right now.
Flow goes from Fender Level Set buffer (I like the mute pre-effects and I swap out basses a lot so it helps to compensate for different input levels without having to change stuff deeper in the rig). Preamp is next (SansAmp in place). It adds a nice drive and helps drive a compressor later in the chain. Next is the Tyler Deluxe. This grew out of the desire to color the top end without compromising a basic punchy low end. The High loop goes to an Alesis Nano Compressor and then the a light bit of MXR carbon copy delay (on the highs only). The lows right now just use the low pass filter to round out the bottom. These all get blended together with the original signal and proceed to the amp / DI. There is a power supply under the Elf to power the system and I threw in a tuner because it still fit. The amazon binder case has an additional binder shell for protection and rigidity. I'm playing with swapping out the SansAmp pre with other pre's for different tones but I do like the overall drive of the SansAmp. So far it has been pretty reliable and helps me repeat my "signature tone" better on different gigs and sessions.

 

[eeyorebass]

It depends on the sensitivity of the amp and how hot the bass is. There's 9dB of output gain on the EQ section with the eq engaged, this is plenty for a hotter bass but maybe not enough for say a passive P. The maximum output level is plenty with a 12V or 18V power supply if there's enough gain.

So, back on topic to this thread, is running into an effects loop return the same as running into a power amp input, e.g. the signal level needs to be stronger to drive the amp? or are effects loop returns generally more sensitive than a stand alone power amp input? If an effects loop is more sensitive, you'd have more options for driving it, and that would be another vote in favor of the integrated amp head, even if you are bypassing the built-in pre.

 

[jnewmark]

Don't really have a horse in this race, but enjoy the discussion. I have tried using a preamp from a bass head, in to the Return of another, more powerful bass head, numerous times, with mixed results. Did it sound louder than just using the built in pre with the already built in power amp? Yes, but did it "sound" the same as before, just louder ? More times than not, the answer was no. Case in point, the Walkabout head. Most of us were dying for a more powerful Walkabout head than the 300 watts the Walkabout had. We loved the tone, but wanted more juice. I tried the Preamp from the WA in to numerous other, more powerful bass heads, and what I got was something louder, but, tone wise , not the same as the WA with its built in power amp. I really believe that the Walkabout was meant to be paired with its internal power amp, it just did not sound the same with other bass head power amps. I also tried other bass head preamps in to other bass head power amps with similar results. The exception was the GK MB200 head, which sounded pretty good or similar when plugged in to the Return of other, more powerful bass heads. YMMV.

 

[agedhorse]

So, back on topic to this thread, is running into an effects loop return the same as running into a power amp input, e.g. the signal level needs to be stronger to drive the amp? or are effects loop returns generally more sensitive than a stand alone power amp input? If an effects loop is more sensitive, you'd have more options for driving it, and that would be another vote in favor of the integrated amp head, even if you are bypassing the built-in pre.

Most (not all) effects returns end up being roughly +4dBu nominal sensitivity but have enough makeup gain to handle -10dBu.

 

[eeyorebass]

Most (not all) effects returns end up being roughly +4dBu nominal sensitivity but have enough makeup gain to handle -10dBu.

Thanks!

 

[Al Kraft]

Case in point, the Walkabout head. Most of us were dying for a more powerful Walkabout head than the 300 watts the Walkabout had. We loved the tone, but wanted more juice. I tried the Preamp from the WA in to numerous other, more powerful bass heads, and what I got was something louder, but, tone wise , not the same as the WA with its built in power amp. I really believe that the Walkabout was meant to be paired with its internal power amp, it just did not sound the same with other bass head power amps.

Absolutely true as much of the classic WA sound was the fortuitous interaction of a quirky design (my characterization) that worked in that package at that power level, but didn't scale up well/easily. Many folks thought that buying one of the larger output M-Pulse heads would "obviously get you a louder WA" but those heads never quite matched the signature WA sound which was heavily rooted in the artifacts/behaviors of the interaction between the WA pre and power sections.

As is often the case with other things in life, the end result is a lot more than the simple sum of the individual parts might indicate. As always, YMMV!

 

[Nebadon2000]

Also, the GR Bass Mini One does have a preamp, but it's also 380 watts, super small, and set flat is super transparent.

GR Bass also has 'Pure' switch on other heads and this amp [below link] 800watts and less $ than Mesa D-350 and similar $ to 300-350 watt Bass Heads from other quality Companies

Link Removed

They did have a 350 watt version but I don't see it listed anymore for sale but it is on their website [GR 350 PURE AMP]

 

[moon-bass]

GR Bass also has 'Pure' switch on other heads and this amp [below link] 800watts and less $ than Mesa D-350 and similar $ to 300-350 watt Bass Heads from other quality Companies

Link Removed

They did have a 350 watt version but I don't see it listed anymore for sale but it is on their website [GR 350 PURE AMP]

I didn't mention the 800 because the OP wasn't looking for that much power, but yeah, it's a great amp. Built in tuner as well. I have both eh Mini and the 800. Superb amps.

 

[radvbass]

I apologize taking this off track. I haven't posted much so it is part of my learnings.

 

[Jazzdogg]

I think the idea is that the power section are transparent, no? You can go with separate to have flexibility through swapping preamps (there are PLENTY of stand-alone power amps out there to choose from, especially used if you don’t mind heavy) but I doubt you are going to save any money this way.

The way Mesa has combined their pre- and power-amps in the Subway series seems brilliant to me.