Enjoy the benefits of a premium membership!
Upgrade Account
-
TalkBass has been independent since 1998. Add your voice.
Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
Join free Log in
Want zero display ads or expanded classifieds tools? Compare plans.
TC Electronic RH750 ???!??
- Thread starter boriology101
- Start date
- Status
I took the RH750 and Golight 2x10 (8ohm) to rehearsal tonight and struggled with it a bit. I took the Golight 2x10 because it seemed louder at the same settings that the TC BC210 cab I have. The amp just doesn't seem that loud. I had the master dimed and gain at about 9 0'clock and still had trouble hearing it in the mix a bit.
Not sure what it is about that BG500 2x10, but that thing sure projects. I guess I could get another Golight 2x10, but wondering that will even be enough for louder venues.
Not sure what it is about that BG500 2x10, but that thing sure projects. I guess I could get another Golight 2x10, but wondering that will even be enough for louder venues.
it might be the Golight 2x10 the RH750 is a really powerful and loud amp, what's the volume like with the golight 4x10?
About RH750 freq. response.
I have a brand new RH750, I am building 2 1x15 cabinets based on the Kappalite 3015, non LF. One of them will have a large, powerful and loud horn capable of reproducing mids, and a custom crossover.
Yesterday I "dry-assembled" one of the cabinets to measure the box tuning frequency. The idea: If I tune the box a little bit higher I could have over-excursion problems in the B-string, if I tune a little bit too low, I lose some deep bass response (over 40 Hz), and I gain a bit under this fequency. If I tune too low, I could start with over-excursion problems around 70 Hz.
Finally my tuning was almost OK, I got 42 Hz instead of the calculated ideal of 43 Hz. Then I wondered the following (I was naive and ignorant about this question): Are bass heads (and the RH-750 in particular) flat till very low frequencies or do they roll at certain reasonably frequency to avoid wasting energy and avoid over-excursion in "normal" bass cabinets? Well, I had all those cables on my table, soundcard and SW configured so I decided to run a couple of tests.
Conclusions:
I suspect this is common with bass heads (and possibly what makes them sound subjectively "good" or "bad" when paired with certain cabs), but anyway the RH750 is anything but flat.
With all controls flat, there is a "hump" at 73 Hz, below which amplitude decreases rapidly. Sorry I did not measure it, but the -3dB point respect to the "flat" zone is around 42 Hz. I am sure this could "make sound good" many reasonable cabinets out there.
The good thing is that even boosting deep bass (reducing bass frequency and boosting level), there some -5dB attnuation below 37 Hz, so my spakers will be protected from over-excursion at full power, even if I tune my box a couple of Hz higher (which could boost my deep bass in the range 55....120 Hz. I´ll probably do that: I will cut my shelf power by some 16mm.
To test freq. response I injected signal from a EMU1616 soundcard. I took the output from the loudspeaker connector back to a differntial input on the EMU (to avoid any problem with ground loops if the RH750 is bridged). I connected my cab under test in parallel to listen to any problem. Once I saw initial freq. response plots I disconnected the cab and check that the response was the same (expected, but not 100% sure). I know the head was operating almost in open circuit, but this is allowed even at high power levels.
The only thing that is not "real" is the power level: I didn't have a suitable power attenuator, so my master was low. It is very possible that TC implemented some kind of "loudness" equalization, boosting bass at low power levels. At the end, they claim they have a "very advanced power management". Increasing levels by a factor of some 10dB did not change anything, but I was anyway far from some dozen volts in the output (I don´t want to fry the EMU!)
And once I had all the cables and soundcard configured and SW running I run a few more tests on some eq controls. In general there is a very noticeable roll-off of high frequencies ("Ampeg sound"?), that is dependant on the Tweetertone control.
I share the images.
I did not run every possibility, it is time consuming.
All measurements done with swept sinewave tones, not white noise. All without compressor and tubetone, gain some -3dB below saturation point.
It's a bit difficult for me to paste and add caption to images, so I posted once the link to all figures. Their filemanes could be enough to understand the EQ settings:
[Invalid or Expired Link Removed]
I will add pics from the whole stuff (cab, SW, amp, Soundcard) later, it's not convenient for me to do it now.
I have a brand new RH750, I am building 2 1x15 cabinets based on the Kappalite 3015, non LF. One of them will have a large, powerful and loud horn capable of reproducing mids, and a custom crossover.
Yesterday I "dry-assembled" one of the cabinets to measure the box tuning frequency. The idea: If I tune the box a little bit higher I could have over-excursion problems in the B-string, if I tune a little bit too low, I lose some deep bass response (over 40 Hz), and I gain a bit under this fequency. If I tune too low, I could start with over-excursion problems around 70 Hz.
Finally my tuning was almost OK, I got 42 Hz instead of the calculated ideal of 43 Hz. Then I wondered the following (I was naive and ignorant about this question): Are bass heads (and the RH-750 in particular) flat till very low frequencies or do they roll at certain reasonably frequency to avoid wasting energy and avoid over-excursion in "normal" bass cabinets? Well, I had all those cables on my table, soundcard and SW configured so I decided to run a couple of tests.
Conclusions:
I suspect this is common with bass heads (and possibly what makes them sound subjectively "good" or "bad" when paired with certain cabs), but anyway the RH750 is anything but flat.
With all controls flat, there is a "hump" at 73 Hz, below which amplitude decreases rapidly. Sorry I did not measure it, but the -3dB point respect to the "flat" zone is around 42 Hz. I am sure this could "make sound good" many reasonable cabinets out there.
The good thing is that even boosting deep bass (reducing bass frequency and boosting level), there some -5dB attnuation below 37 Hz, so my spakers will be protected from over-excursion at full power, even if I tune my box a couple of Hz higher (which could boost my deep bass in the range 55....120 Hz. I´ll probably do that: I will cut my shelf power by some 16mm.
To test freq. response I injected signal from a EMU1616 soundcard. I took the output from the loudspeaker connector back to a differntial input on the EMU (to avoid any problem with ground loops if the RH750 is bridged). I connected my cab under test in parallel to listen to any problem. Once I saw initial freq. response plots I disconnected the cab and check that the response was the same (expected, but not 100% sure). I know the head was operating almost in open circuit, but this is allowed even at high power levels.
The only thing that is not "real" is the power level: I didn't have a suitable power attenuator, so my master was low. It is very possible that TC implemented some kind of "loudness" equalization, boosting bass at low power levels. At the end, they claim they have a "very advanced power management". Increasing levels by a factor of some 10dB did not change anything, but I was anyway far from some dozen volts in the output (I don´t want to fry the EMU!)
And once I had all the cables and soundcard configured and SW running I run a few more tests on some eq controls. In general there is a very noticeable roll-off of high frequencies ("Ampeg sound"?), that is dependant on the Tweetertone control.
I share the images.
I did not run every possibility, it is time consuming.
All measurements done with swept sinewave tones, not white noise. All without compressor and tubetone, gain some -3dB below saturation point.
It's a bit difficult for me to paste and add caption to images, so I posted once the link to all figures. Their filemanes could be enough to understand the EQ settings:
[Invalid or Expired Link Removed]
I will add pics from the whole stuff (cab, SW, amp, Soundcard) later, it's not convenient for me to do it now.
Well, in the first picture (Tweetertone control centered) you can see it hits -10dB at some 3400 kHz, this could correspond well with users' comments on the RH450. Tweetertone to the far left is very radical. Similar to some "really old school" amps. I gigged 1 year ago an old tube Yamaha combo, graphic EQ ended up in 1.8 KHz if I remember well.
I has the amp, but I cannot use it the way it deserves, I am building the cabs, I have to work during the day and tomorrow I go on vacation. I only did the bad part of GAS: Paying for the new gear, but not being able to play with it!!
I has the amp, but I cannot use it the way it deserves, I am building the cabs, I have to work during the day and tomorrow I go on vacation. I only did the bad part of GAS: Paying for the new gear, but not being able to play with it!!
- Apr 3, 2003
- 35,515
- 19,941
- Disclosures
- Editor-in-Chief, Bass Gear Magazine
FYI, we recently completed our full review of the RH450 in Link Removed, and Tom Lees does a pretty thorough technical analysis (including frequency range plots).
That is not really the best way to summarize.
The TweeterTone varies the upper frequency at which high end is sharply rolled off. It does not change the frequency range of the tweeter on the cab. That's set by the cab's crossover. In effect, the TT will seem to have a similar behavior as the attenuator, but for different reasons.
The attenuator is literally like a volume control, whereas all frequencies are present, but attenuated by varying amounts.
The TweeterTone will seem to control volume but not because it's literally attenuating the signal to the cab, but rather, by narrowing the frequency range passed to the cab.
So you can reduce the overall signal, or you can reduce the usable range of the signal. They'll sound different, but from a practical perspective, to the human ear, they'll both just generally feel like attenuation of the high end.
- Apr 3, 2003
- 35,515
- 19,941
- Disclosures
- Editor-in-Chief, Bass Gear Magazine
Yes. Check out Tom Lees technical review of the RH450 in issue #6. He has an "all controls at noon vs optimally flat" chart, and he shows pictures of how to set the controls to achieve his "optimally flat" setting.
1) Very interesting. Yesterday I browsed this review and didn't pay attention to some details. They make a lot of sense now.
2) I suspected when the amp is set "flat", it´s freq. response could be "pleasant" or "vintage"... but never flat or "HiFi". Now I can see the big gap between what players need and what players think they need. Me included (no difference being an engineer or after 31 years playing
)3) I was not drunk or made a bad connection yesterday, the amp cuts deep lows to protect speakers and maximize perceived loudness. This was my ultimate goal yesterday: decide to tune my cab to be capable of extreme lows or "like most cabs". Fortunately the driver (3015 non-LF) can take 1 or 2 dB of advantage over the LF when used with this head. I will tune my cab a couple of Hz higher, no risk to fart-out using the low-B string even with (reasonable) bass boost.
Perhaps I should have accepted a good deal on the 410L Schroeder cabinet instead of all the work I am doing.
4) Traditional forum users are going to ban me but... this digital class D amplifier full of SMD components and so on is the closest thing to a tube amp I´ve seen / heard.
5) More importantly, great review, thanks and thanks!
I've a couple more rehearsals and a gig with it and this thing is growing on me. It's so functional I've decided to make due with it even if its not my favorite tone. Going to return the BG500 and keep the RH750. No just deciding if I want to trade off some of my cabs for another SWR Golight 2x10 or just go with the mix match of the Golight 2x10 and TC BC210 cab.
Well I settled on a setup. RH750 + 2 SWR Golight Jr. 2x10's. Sounds great, plenty of volume and is old man back safe. Gigging this setup tonight.
I tried to stack vertical, but I just never dig that sound. Not sure what happens acoustically, but I can't get with it. Going to put the cabs on the ground on their left sides, side by side. That sounds best to me.
Oh and I kept the BX500 has a back for now. Going to leave it in the bag and take it to gigs just in case. Will likely sell it after a few solid gigs with the RH750 though. Hoping they are reliable.
I tried to stack vertical, but I just never dig that sound. Not sure what happens acoustically, but I can't get with it. Going to put the cabs on the ground on their left sides, side by side. That sounds best to me.
Oh and I kept the BX500 has a back for now. Going to leave it in the bag and take it to gigs just in case. Will likely sell it after a few solid gigs with the RH750 though. Hoping they are reliable.
Don't be shy about working with the EQ (again) with the vertical stack (part of this might be what your ear is used to as well).
I don't feel fanatical about vertical stacking (as some seem to), but in a band mix, it can sure help you hear yourself better and possibly your sound projection out in the audience (if you need it).
Whatever works best for you though!
Need help from P-bass players!
I have done like 15 gigs with my RH750 now and I must say that my bass sound haven't ever been better! Played it on many different cabs, from Ampeg 8x10 to different 1x12 and it has been quite easy to dial in "my" sound. All gigs done with Fender Jazz bass and no pedals. (First amp I could leave my pedal board at home which was one of my goals with buying the RH750.)
But yesterday I took my P-bass (passive) to a pop gig and it sounded crap. I couldn't dial in a good Pbass-sound at all. Not blaming the 750 here as I was in a bit of time pressure but it still worried me a bit.
So, how do you EQ your RH750 to get that soul Pbass sound?
I have done like 15 gigs with my RH750 now and I must say that my bass sound haven't ever been better! Played it on many different cabs, from Ampeg 8x10 to different 1x12 and it has been quite easy to dial in "my" sound. All gigs done with Fender Jazz bass and no pedals. (First amp I could leave my pedal board at home which was one of my goals with buying the RH750.)
But yesterday I took my P-bass (passive) to a pop gig and it sounded crap. I couldn't dial in a good Pbass-sound at all. Not blaming the 750 here as I was in a bit of time pressure but it still worried me a bit.
So, how do you EQ your RH750 to get that soul Pbass sound?
funkymagnusb said:
For my P I run a couple extra clicks of low mid and high mid (factory centers) with the compressor at 9 o'clock (5-6 clicks I think). I also dial in about 3-5 clocks of tubetone for some P goodness. Bass and treble are flat. That does it for me.
Thanks. I was just about to revisit this head with my new VP5, and this sounds like a great starting point for me, too. What cab(s) are you using?
Hey people, one question.
Do you listen any "clicks" when pressing the Mute button on your RH750?
My RH750 does them, not very loud, but it's a little annoying. IIRC musicman20 was talking about it some time ago. But as an answer on the TC facebook page it seems normal...
Do you listen any "clicks" when pressing the Mute button on your RH750?
My RH750 does them, not very loud, but it's a little annoying. IIRC musicman20 was talking about it some time ago. But as an answer on the TC facebook page it seems normal...
- Status
